National Immunization Survey-Child 

A User’s Guide for the 2021

Public-Use Data File

Centers for Disease Control and Prevention

National Center for Immunization

and Respiratory Diseases

Presented by:

NORC at the University of Chicago 

December 2022
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Acknowledgments 

The development and production of the NIS-Child public-use data files is a team effort that has included 

contributions from many individuals (listed in alphabetical order) in the two organizations:

National Center for Immunization and Respiratory Diseases, CDC – Michael Chen, Laurie D. ElamEvans, Holly A. Hill, James A. Singleton, Chalanda S. Smith, and Larry Wilkinson.

NORC at the University of Chicago – Rachel Francis, Benjamin Skalland, Kirk Wolter, and Maggie 

Yarbrough.
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Table of Contents 

1. Introduction........................................................................................................................................ 1

2. Sample Design .................................................................................................................................... 7

2.1. The NIS-Child RDD Telephone Survey..................................................................................... 7

2.2. The NIS-Child Provider Record Check...................................................................................... 9

2.3. Summary of Data Collection .................................................................................................... 10

2.4. Informed Consent, Security, and Confidentiality of Information............................................. 12

3. Content of NIS-Child Questionnaires............................................................................................ 14

3.1. Content of the Household Questionnaire.................................................................................. 14

3.2. Content of the Immunization History Questionnaire (IHQ)..................................................... 16

4. Data Preparation and Processing Procedures............................................................................... 18

4.1. Data Preparation ....................................................................................................................... 18

4.1.1. Editing in the CATI System ........................................................................................ 19

4.1.2. Post-CATI Edits .......................................................................................................... 19

4.1.3. Editing of Provider Data.............................................................................................. 20

4.2. Limitations of Data Editing Procedures.................................................................................... 21

4.3. Variable-Naming Conventions................................................................................................. 22

4.4. Missing Value Codes................................................................................................................ 22

4.5. Imputation for Item Non-Response .......................................................................................... 22

4.6. Vaccine-Specific Recoding of Verbatim Responses................................................................ 24

4.7. Composite Variables................................................................................................................. 24

4.8. Subsets of the NIS-Child Data.................................................................................................. 27

4.9. Confidentiality and Disclosure Avoidance ............................................................................... 27

5. Quality Control and Quality Assurance Procedures.................................................................... 28

6. Sampling Weights............................................................................................................................ 29

6.1. Base Sampling Weight ............................................................................................................. 30

6.2. Adjustments for Non-Resolution of Telephone Numbers, Screener Non-Response, and 

Interview Non-Response .......................................................................................................... 30

6.3. Adjustment for Multiple Cellular Phones and Deriving Annual Weights................................ 31

6.4. Calibration ................................................................................................................................ 32

6.5. Adjustment for Provider Non-Response................................................................................... 34

6.6. Sampling Weights for Territories............................................................................................. 37

7. Contents of the Public-Use Data File ............................................................................................. 38

7.1. Section 1: ID, Weight, and Flag Variables............................................................................... 42

7.2. Section 2: Household-Reported Vaccination and Chickenpox Information............................. 42
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7.3. Section 3: Demographic, Socio-Economic, and Other Household/Child Information ............. 42

7.4. Section 4: Geographic Variables.............................................................................................. 44

7.5. Section 5: Number of Providers Identified and Consent Variables .......................................... 44

7.6. Section 6: Number of Responding Providers Variables ........................................................... 44

7.7. Section 7: Characteristics of Providers Variables..................................................................... 45

7.8. Section 8: Provider-Reported Up-To-Date Vaccination Variables .......................................... 47

7.8.1. Hib Up-To-Date Variables .......................................................................................... 50

7.8.2. Rotavirus Up-To-Date Variables................................................................................. 52

7.9. Section 9: Provider-Reported Age-At-Vaccination Variables.................................................. 53

7.10. Section 10: Health Insurance Module Variables ...................................................................... 54

8. Analytic and Reporting Guidelines................................................................................................ 56

8.1. Use of NIS-Child Sampling Weights........................................................................................ 57

8.2. Estimation and Analysis ........................................................................................................... 58

8.2.1. Estimating Vaccination Coverage Rates ..................................................................... 58

8.2.2. Estimating Standard Errors of Vaccination Coverage Rates ....................................... 59

8.3. Combining Multiple Years of NIS-Child Data ......................................................................... 60

8.3.1. Estimation of Multi-Year Means................................................................................. 60

8.3.2. Estimation of Multi-Year Contrasts............................................................................. 63

9. Summary Tables.............................................................................................................................. 72

10. Assessment of Total Survey Error.................................................................................................. 74

11. Limitations........................................................................................................................................ 84

12. Citations for NIS-Child Data.......................................................................................................... 85

13. References......................................................................................................................................... 92
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Appendices

Appendix A: Glossary of Abbreviations and Terms................................................................................... 97

Appendix B: Summary Statistics for Sampling Weights by Estimation Area.......................................... 100

Appendix C: Flags for Inconsistent Values in the Breastfeeding Data..................................................... 104

Appendix D: Programs for Estimation: Examples of the Use of SUDAAN, SAS, and R to Estimate 

Vaccination Coverage Rates and Their Standard Errors, and an Example of the Production of a CrossTabulation and Chart................................................................................................................................. 105

Appendix E: Alphabetical Listing of Variables that are in the 2004-2021 Public-Use Data Files........... 137

Appendix F: Summary Tables.................................................................................................................. 198

Appendix G: Trends in NIS-Child Response Rates and Vaccination Coverage Rates, 1995-2021 ......... 207

Appendix H: Vaccine Type Codes............................................................................................................ 215

Appendix I: Key NIS-Child Response Rates by Area .............................................................................. 216
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List of Tables and Figures

Table 1: Selected Operational Results of Q1/2021-Q4/2021 NIS-Child Data Collection (Excluding 

U.S. Territories) ..................................................................................................................... 13

Table 2: Content of the Household Interview, National Immunization Survey - Child, 2021............. 15

Table 3: Distribution of Age (in Days) at the Birth Dose of Hepatitis B Vaccine, National 

Immunization Survey - Child, 2021 ....................................................................................... 24

Table 4: Weighted Distribution of Children by Race/Ethnicity and Corresponding Combined Vaccine 

Series (4:3:1:3*:3:1:4), Pneumococcal, and Varicella Vaccination Coverage Estimates, 

National Immunization Survey - Child, 2021 ........................................................................ 26

Table 5: NIS-Child Variables Commonly Used in Analyses or for Published Estimates.................... 39

Table 6: Vaccine Categories and Vaccine Types, National Immunization Survey - Child, 2021 ....... 49

Table 7: Up-To-Date Variables for Hib, National Immunization Survey - Child, 2009-2021 ............ 51

Table 8: Up-To-Date Variables for Vaccine Series Including Hib, National Immunization Survey - 

Child, 2009-2021 ................................................................................................................... 52

Table 9: Summary of Weights and Stratum Variables, National Immunization Survey - Child, 2021 58

Table 10: Cross-Walk between ITRUEIAP, ESTIAP, ESTIAP06-ESTIAP21, and Common 

Denominator Estimation Area (CDIAP), National Immunization Survey - Child, 2021 ...... 65

Figure 1: Scatter Plot of Percentage Point Difference between NIS-Child and IISAR Vaccination 

Coverage Rates for the Combined 7-Vaccine Series vs. IIS Child Participation Rate (CPR) 

with Regression Line: 56 Estimation Areas ........................................................................... 77

Table 11: Mean and 95% Credible Interval for the Estimated Total Survey Error (TSE) Distribution 

and Component Error Distributions for National Vaccination Coverage Rate Estimates, 

National Immunization Survey - Child, 2021 ........................................................................ 81

Table 12: Difference Between the Estimates for the Bridging Birth Cohort by Age 19 Months, 

National Immunization Survey - Child, 2020 vs. 2021 .......................................................... 83

Table B.1: Distribution of Sampling Weights for Children with Completed Household Interviews, 

National Immunization Survey - Child, 2021 ...................................................................... 100

Table B.2: Distribution of Sampling Weights for Children with Adequate Provider Data, National 

Immunization Survey - Child, 2021 ..................................................................................... 102

Table E.1 Alphabetical Listing of Variables that are in the 2004-2021 Public-Use Data Files........... 137

Table F.1: Estimated Population Totals and Sample Sizes of Children 19-35 Months of Age by State 

and Estimation Area, National Immunization Survey - Child, 2021 ................................... 198

Table F.2: Estimated Population Totals and Sample Sizes for Age Group by Maternal Education, 

National Immunization Survey - Child, 2021 ...................................................................... 200

Table F.3: Estimated Population Totals and Sample Sizes for Age Group by Poverty Status, National 

Immunization Survey - Child, 2021 ..................................................................................... 201

Table F.4: Estimated Population Totals and Sample Sizes for Race/Ethnicity by Poverty Status, 

National Immunization Survey - Child, 2021 ...................................................................... 202

Table F.5: Estimated Population Totals and Sample Sizes for Age Group by Race/Ethnicity, National 

Immunization Survey - Child, 2021 ..................................................................................... 203

Table F.6: Estimated Population Totals and Sample Sizes for Age Group by Sex, National 

Immunization Survey - Child, 2021 ..................................................................................... 204
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Table F.7: Estimated Vaccination Coverage with Individual Vaccines and Selected Vaccination Series 

Among Children 19-35 Months of Age by State and Estimation Area, National 

Immunization Survey - Child, 2021 ..................................................................................... 205

Table G.1: Key Indicators from Landline Sample Household and Provider Data Collection by Survey 

Year, National Immunization Survey - Child, 1995-2017 ................................................... 207

Figure G.1: Trends in Landline Sample Key Indicators from Household and Provider Data Collection by 

Survey Year, National Immunization Survey - Child, 1995-2017 ....................................... 208

Table G.2: Key Indicators from Cellular Phone Sample Household and Provider Data Collection by 

Survey Year, National Immunization Survey - Child, 2011-2021 ....................................... 209

Figure G.2: Trends in Cellular Phone Sample Key Indicators from Household and Provider Data 

Collection by Survey Year, National Immunization Survey - Child, 2011-2021 ................ 210

Table G.3: CASRO Response Rate for the Combined Landline and Cellular Phone Samples by Survey 

Year, National Immunization Survey - Child, 2011-2017 ................................................... 212

Figure G.3: Trend in CASRO Response Rate for the Combined Landline and Cellular Phone Samples by 

Survey Year, National Immunization Survey - Child, 2011-2017 ....................................... 212

Table G.4: Vaccine-Specific Coverage Levels Among Children Age 19-35 Months in the United States 

by Survey Year, National Immunization Survey - Child, 1995-2021 .................................. 213

Figure G.4: Trends in Vaccine-Specific Coverage Levels among Children 19-35 Months of Age in the 

United States by Survey Year, National Immunization Survey - Child, 1995-2021 ........... 214

Table H.1: 2021 NIS-Child Vaccine Type Codes .................................................................................. 215

Table I.1: Key Indicators for the Cellular Phone Sample by Estimation Area, National Immunization 

Survey - Child, 2021 ............................................................................................................ 216
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Convention for Bolding Text 

The Data User’s Guide uses bold font 

to highlight substantive changes in 

the methodology or study design 

from the previous year’s Guide. 
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1. Introduction 

In 1992, the Childhood Immunization Initiative (CII) (CDC 1994) was established to 1) improve the 

delivery of vaccines to children; 2) reduce the cost of childhood vaccines; 3) enhance awareness, 

partnerships, and community participation; 4) improve vaccinations and their use; and 5) monitor 

vaccination coverage and occurrences of disease. The Healthy People 2030 objectives set the following

targets for vaccination coverage in young children: maintain the vaccination coverage level of 1 dose of 

the measles, mumps, and rubella (MMR) vaccine in children by age 2 years at 90.8% or higher; increase 

the vaccination coverage level of 4 doses of the diphtheria and tetanus toxoids and acellular pertussis 

(DTaP) vaccine in children by age 2 years to 90.0%; and reduce the proportion of children who get no 

recommended vaccines by age 2 years below 1.3%. To fulfill the CII mandate of monitoring vaccination 

coverage and marking progress toward achieving those objectives, the National Immunization Survey - 

Child (NIS-Child) was implemented by the National Center for Immunization and Respiratory Diseases 

(NCIRD) and the National Center for Health Statistics (NCHS) of the Centers for Disease Control and 

Prevention (CDC) in 1994. From 1994 to 2014, the NIS-Child was conducted jointly by NCIRD and 

NCHS; since 2015, the NIS-Child has been conducted by NCIRD.

The target population for the NIS-Child is non-institutionalized children aged 19 through 35 months 

living in United States households at the time of the interview. The official coverage estimates reported 

from the NIS-Child are proportions of children up-to-date with respect to the requisite numbers of doses 

of all routinely recommended vaccines for this age group (Wodi et al. 2021). These vaccines and their 

recommended numbers of doses are: 

● diphtheria and tetanus toxoids and acellular pertussis vaccine adsorbed, diphtheria and tetanus 

toxoids and pertussis vaccine, or diphtheria and tetanus toxoids adsorbed (DTaP/DTP/DT) – 4 

doses;

● poliovirus vaccine (polio) – 3 doses;
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● measles, mumps, and rubella vaccine (MMR) – 1 dose;

● Haemophilus influenzae type b conjugate vaccine (Hib) – 3 or 4 doses depending on product 

type;

● hepatitis B vaccine (Hep B) – 3 doses;

● varicella (chicken pox) vaccine (VAR) – 1 dose;

● pneumococcal conjugate vaccine (PCV) – 4 doses;

● hepatitis A vaccine (Hep A) – 2 doses; 

● influenza vaccine; (For the recommended number of doses of influenza vaccine and other 

vaccines, see http://www.cdc.gov/vaccines/hcp/acip-recs/vacc-specific/index.html.)

● rotavirus vaccine (RV) – 2 or 3 doses depending on product type.

In addition to these vaccines, interest focuses on the combined vaccine series 4:3:1:3*:3:1:4 (4+ 

DTaP/DTP/DT; 3+ polio; 1+ measles-containing vaccine (MCV); full series Hib, i.e., 3 or 4 doses 

depending on type of vaccine received; 3+ Hep B; 1+ varicella at or after 12 months of age; and 4+ PCV). 

The NIS-Child collects data on each of these vaccines. Varicella vaccine was added in Quarter 3, 1996, 

pneumococcal conjugate vaccine in Quarter 4, 2000, influenza vaccine and hepatitis A vaccine in Quarter 

1, 2003, and rotavirus vaccine in Quarter 3, 2007. The remainder of the vaccines have been included in 

the NIS-Child from its start in 1994. Information about current and past recommendations for each 

vaccine can be found at https://www.cdc.gov/vaccines/hcp/acip-recs/index.html. 

The NIS-Child uses random digit dialing (RDD) telephone survey methodology to identify households 

containing children in the target age range, and interviews are conducted with the adult who is most 

knowledgeable about the child’s vaccinations. With consent of the child’s parent or guardian, the NISChild also contacts (by mail) the child’s health care provider(s) to request information on vaccinations 
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from the child’s medical records. Since 2005, NIS-Child sampling, data collection, and weighting

operations have been conducted by NORC at the University of Chicago.

Samples of telephone numbers are drawn independently for each calendar quarter within selected 

geographical areas, or strata. In 2021, there are 59 geographic strata for which vaccination coverage levels 

can be estimated (see Table F.1), including 5 local areas; the remaining 54 estimation areas are either an 

entire state, the District of Columbia, a U.S. territory (the U.S. Virgin Islands, Guam, or Puerto Rico), or a 

“rest of state” area. For states with local and “rest of state” estimation areas, estimates for the whole-state 

area can be produced as well. This design makes it possible to produce annual estimates of vaccination 

coverage levels for each state or territory, the District of Columbia, each of the 5 local estimation areas, 

and each “rest of state” area, with a specified degree of precision (a coefficient of variation of 

approximately 7.5%). Further, by using the same data collection methodology and survey instruments in 

all estimation areas, the NIS-Child produces comparable vaccination coverage levels across estimation 

areas and over time. 

When the NIS-Child was established in 1994, 78 areas were chosen for sampling strata, including the 50 

states, 6 urban areas that receive federal Section 317 immunization grants (Bexar County, TX; Chicago, 

IL; District of Columbia; Houston, TX; New York City, NY; Philadelphia County, PA), and 22 other 

urban areas. These areas were called “Immunization Action Plan” (IAP) areas in reference to plans 

developed to improve vaccination coverage following the resurgence of measles during 1989-1991. In 

2005 and 2006, selected non-awardee IAP areas – areas that do not receive separate Section 317 funds – 

were “rotated off” (i.e., the sample design no longer ensured adequate sample size to produce estimates 

for the area) and replaced by new areas “rotated on” (i.e., the sample design did ensure adequate sample 

size to produce estimates for the area). Starting in 2007, the base NIS-Child geographic strata included 56 

areas (5 sub-state awardee urban areas, the District of Columbia, and 50 state or “rest of state” areas). In 

addition, starting in 2007, state immunization programs could choose additional city/county areas of 

interest to have adequate sample size to produce estimates for the area, using their Section 317 funds. In 
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2021, the NIS-Child included the U.S. Virgin Islands, Guam, and Puerto Rico as additional 

estimation areas. As noted throughout this report, some procedures differed for U.S. territories when 

compared to the rest of the U.S., including the creation of separate survey weight variables for analyses 

that are to include territories.

The 59 = 56 + 3 areas are called estimation areas. Table 10 in Section 8 shows a cross-walk of estimation 

areas between years. To maintain consistency with past NIS-Child public-use data files, or PUFs, variable 

names and descriptions continue to use the term “IAP” to designate areas included as strata, which was 

the term used prior to 2008. The changing geographic strata over time will not cause a problem with bias 

in estimation of state and national coverage levels since the geographic strata are nested within state.

Data for the U.S. Virgin Islands and Guam are not included in the 2021 public-use data file to 

protect respondent confidentiality, as the sampling fractions were larger in these small-population 

areas. Interested researchers can access data for the U.S. Virgin Islands and Guam by submitting a 

proposal and working through the Research Data Center. The link and guidelines for developing a 

proposal are located at the following URL: www.cdc.gov/rdc. 

For the 2021 NIS-Child, telephone interviewing began on January 7, 2021 and ended on February 

4, 2022. Provider data collection extended from January 2021 through April 2022. A total sample, 

including the U.S. territory samples, of approximately 21.1 million telephone numbers yielded 

household interviews for 36,480 children, 18,532 of whom had adequate provider data (i.e., 

provider-reported vaccination data adequate to determine whether the child was up-to-date with 

respect to the recommended immunization schedule). The 2021 NIS-Child public-use data file, 

which includes data from Puerto Rico but does not include data for the U.S. Virgin Islands and 

Guam, contains data for 35,995 children with completed household interviews (34,863 when Puerto 

Rico is excluded), and more extensive data (e.g. provider-reported vaccinations and facility data) 

for 18,319 children with adequate provider data, including 221 unvaccinated children (17,967 
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including 211 unvaccinated children, when Puerto Rico is excluded). Data were collected in the U.S. 

Virgin Islands and Guam in 2021, but children in these areas are not included on the public-use 

data file in order to protect confidentiality. 

Official NIS-Child vaccination coverage estimates are based on the provider-reported vaccination 

histories for each child. Among children with data received from vaccination providers identified in the 

household interview, it must be determined which children have “adequate provider data,” that is, which 

children have provider data adequate to determine whether the child is up to date with respect to the 

recommended immunization schedule. In 2012, the NIS-Child household questionnaire was modified to 

reduce the length of the household interview, decrease respondent burden, and potentially improve 

response rates, with the result that questions that were previously used to define adequate provider data

were no longer available. With this questionnaire change, it was no longer possible to use the same 

definition of adequate provider data as was used prior to 2012, and so beginning in 2012 all children with 

any provider-reported vaccination data are considered to have adequate provider data. See the user’s 

guide for the 2014 NIS-Child public-use data file (NCHS 2015) for more detail about this change and its 

impact. 

The weights included on this public-use data file afford the data analyst the capability of conducting 

several different types of analyses, depending on interests and aims. One can choose to analyze all 

children with completed household interviews or only the subset of children for whom the providerreported data are adequate. One can also choose to include or exclude children who reside in U.S. 

territories in the analysis. Previous NIS-Child public-use data files have also provided analysts with these 

capabilities. Section 6 of this user’s guide provides information about the creation of the weight variables 

included in the 2021 NIS-Child public-use data file, and Section 8 provides guidance for their use. 

Vaccination coverage estimates are available on the ChildVaxView website, 

https://www.cdc.gov/vaccines/imz-managers/coverage/childvaxview/index.html. An article summarizing 
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key findings from the NIS-Child data, as published in the Morbidity and Mortality Weekly Report 

(MMWR), will also be available on this website. Historically, these estimates have been based on NISChild data collected in a single survey year (e.g., the 2021 NIS-Child) and applied to the population of 

children age 19-35 months; since 2018, the estimates on ChildVaxView and in the MMWR are based on 

data pooled over 2-3 survey years (e.g., the 2019-2021 NIS-Child surveys) and apply to the population of 

children in particular annual birth cohorts (e.g., children born in 2018 or 2019). This cohort-based 

approach to estimating vaccination coverage has been described by Singleton et al., (2019) and Singleton 

(2019). The 2021 NIS-Child public-use file and this user’s guide focus on a single survey year (2021) 

and the production of vaccination coverage estimates for children age 19-35 months in 2021. 

Therefore, estimates produced from this public-use file will differ from birth cohort-based 

estimates on ChildVaxView and in the MMWR (Hill et al. forthcoming). Researchers interested in 

analyzing the NIS-Child data by birth year can request access to the required data via the Research 

Data Center (http://www.cdc.gov/rdc). 

The accompanying codebook (NCIRD 2022) documents the contents of the 2021 NIS-Child public-use 

data file. For reference, Appendix E (Alphabetical Listing of Variables in the NIS-Child Public-Use Data 

Files) provides a full list of variables in the 2021 and previous NIS-Child public-use data files. 

Additional information on the NIS-Child is available at: http://www.cdc.gov/vaccines/imzmanagers/nis/about.html. 

For additional information on the NIS-Child public-use data file, please contact the NCIRD Information 

Dissemination Staff: 

Information Dissemination Staff, NCIRD 

1600 Clifton Road

Atlanta, GA 30333

E-mail: cdcinfo@cdc.gov

Internet: http://www.cdc.gov/vaccines/imz-managers/nis/index.html
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2. Sample Design 

The NIS-Child uses two phases of data collection to obtain vaccination information for a large national 

probability sample of young children: an RDD telephone survey designed to identify households with 

children 19 through 35 months of age, followed by the Provider Record Check, a mailed survey to 

children’s vaccination providers. This section summarizes these two phases of data collection. Other 

descriptions of the sample design are given by Ezzati-Rice et al. (1995), Zell et al. (2000), Smith et al. 

(2001a, 2005), and Wolter et al. (2017a). 

2.1. The NIS-Child RDD Telephone Survey 

The NIS-Child RDD telephone survey phase uses independent, quarterly samples of cellular phone 

numbers. Sampling frames were provided by Marketing Systems Group (MSG). Cellular phone numbers 

were sampled within estimation areas in each quarter of 2021. Table F.1 (in Appendix F) lists the 

estimation areas for the 2021 NIS-Child by state and shows the estimated number of children living in 

each state and estimation area in 2021. 

Prior to 2011, the NIS-Child used a single-frame landline RDD sample design. In 2011, a cellular phone 

sample was added, and from 2011-2017, the NIS-Child used a dual-frame landline and cellular phone 

RDD sample design. In 2018, the landline sample was dropped, and the NIS-Child now uses a singleframe cellular phone RDD sample design.

The target sample size of completed telephone interviews in each estimation area is designed to achieve 

an approximately equal coefficient of variation of 7.5% for an estimator of vaccination coverage derived 

from provider-reported vaccination histories, given a true coverage parameter of 50%. Cellular phone 

sample sizes were chosen to meet the target coefficient of variation of 7.5%. 

Since 2019, the NIS sample design has included a modification to increase the efficiency of data 

collection. Immunization Information Systems (IIS) are state or local confidential, computerized, 
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population-based data systems that collect and consolidate vaccination doses administered by 

participating vaccination providers to persons residing in a given geopolitical area. In participating 

geographic estimation areas, a two-phase RDD sample of cellular phone numbers is selected, with the 

second-phase sample stratified by the status of the telephone number in the corresponding IIS: 

• Stratum 1: Phone number associated with a 19-35 month old child in the IIS

• Stratum 2: Phone number associated with a 13-17 year old adolescent in the IIS (but not with a 

19-35 month old child in the IIS)

• Stratum 3: Phone number associated with a 6-18 month or 3-12 year old child in the IIS (but not 

with a 19-35 month old child or 13-17 year old adolescent in the IIS)

• Stratum 4: Phone number not associated with a 6 month to 17 year old child in the IIS

In the second phase of sampling, phone numbers falling into Stratum 1 were oversampled. The method 

was designed to maximize the effective sample sizes for the NIS family of surveys, given fixed cost of 

data collection, within each of the participating geographic estimation areas. For the 2021 sample, there 

were 27 participating areas.1

The design and implementation of the NIS-Child cellular phone sample involves three procedures. First, 

statistical models predict the number of sample telephone numbers needed in each estimation area to meet 

the target precision requirements. Second, the sample for an estimation area is divided into random subsamples called replicates. By releasing replicates as needed, it is possible to spread the interviews for each 

1 The participating geographic areas in 2021 were Alaska, Arkansas, Connecticut, Idaho, Iowa, Kansas, Louisiana, 

Maryland, Michigan, Mississippi, Missouri, Nebraska, Nevada, New Mexico, New York – City of New York, North 

Carolina, North Dakota, Ohio, Rhode Island, South Dakota, Tennessee, Utah, Vermont, Washington, Wyoming, the 

U.S. Virgin Islands, and Puerto Rico. Not all of these areas utilized the IIS-NIS integration design in every quarter 

of 2021. Arkansas and Iowa used the integration design in quarters 3 and 4, and the U.S. Virgin Islands used it only 

in quarter 4.
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sampling area evenly across the entire calendar quarter. Third, an automated procedure eliminates 

numbers on the NIS do-not-call list from the sample before the interviewers dial them. 

In 2014 and 2015, an automated process was implemented to remove cellular phone numbers flagged as 

having no recent activity and that were therefore very likely to be non-working cellular phones. In 2016, a 

different automated process found to be more efficient in removing non-working cellular phone numbers 

was used. Following a July 2016 Federal Communications Commission (FCC) declaratory ruling (FCC 

16-72, CG Docket No. 02-278) stating that the federal government and contractors working on behalf of 

the federal government are not subject to the restrictions on cellular phone dialing in the Telephone 

Consumer Protection Act of 1991 (TCPA, 47 U.S.C. 227), the NIS transitioned from manual dialing of 

cellular phones to auto-dialing cellular phones in November 2016. After this transition, the automated 

process to remove non-working cellular phone numbers was no longer cost effective, and beginning in 

2017 this process was no longer used in the cellular phone sample.

2.2. The NIS-Child Provider Record Check

At the end of the household interview, consent to contact the child’s vaccination provider(s) is requested 

from the parent/guardian. When oral consent is obtained, each provider is mailed an immunization history 

questionnaire. This mail survey portion of the NIS-Child is the Provider Record Check (PRC). 

The instructions ask vaccination providers to mail or fax the immunization history questionnaire back 

upon completion. Two weeks after the initial mailing, a telephone call is made to providers who have still 

not responded, to remind and encourage them to complete the form and either mail or fax the information 

back. In some instances, provider-reported vaccination histories are completed over the telephone. The 

data from the questionnaires are edited, entered, cleaned, and merged with the household information 

from the RDD survey to produce a child-level record.
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2.3. Summary of Data Collection

Table 1 presents selected operational results of NIS-Child data collection for calendar year 2021. To 

facilitate comparisons with prior years, the numbers in Table 1 and discussed in this section exclude the 

U.S. territory samples. Children aged 19 through 35 months during 2021 data collection were born 

between January 2018 and May 2020. 

The total cellular phone sample consisted of 19,630,940 telephone numbers. Of those, 54,719 were 

eliminated before release to the telephone centers as numbers on the NIS do-not-call list. The 

remaining 19,576,221 numbers were sent to the telephone centers to be dialed, and 1,650,700 active 

personal cellular phone numbers (APCNs) were identified, as shown in Row F. Among the 

identified APCNs, 1,395,556 (84.5%) were successfully screened. Of these, 48,887 (3.5%) were 

deemed eligible for the NIS-Child interview. Among the identified eligible respondents, 33,647

(68.8%) completed the interview.

A standard approach for measuring response rates in telephone surveys has been defined by the Council 

of American Survey Research Organizations (CASRO 1982). The CASRO response rate is equivalent to 

“RR3” of AAPOR Standard Definitions (AAPOR 2016). In 2021, the CASRO response rate (Table 1, 

Row J) was 22.9%. The CASRO response rate equals the product of the resolution rate (39.4%, 

Row E), the screening completion rate (84.5%, Row G), and the interview completion rate among 

eligible households (68.8%, Row I). The resolution rate is the percentage of the total telephone numbers 

selected that are classifiable as non-working, non-residential, or residential. The screening completion 

rate is the percentage of known households that are successfully screened for the presence of age-eligible 

children. The interview completion rate is the percentage of households with one or more age-eligible 

children who complete the household interview.

Row K of Table 1 shows that household interviews were completed on behalf of 34,863 age-eligible 

children. Rows L through O give results for the Provider Record Check phase. Specifically, Row L 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 11

gives the rate of obtaining oral consent from the household respondent to contact the child’s

vaccination providers – 61.4% in 2021. 

The number of immunization history questionnaires mailed to vaccination providers exceeds the number 

of completed interviews for children with consent because some children have more than one vaccination 

provider. Of the questionnaires mailed to providers of children, 22,970 (90.8%, Row N) were 

returned. Among the children with completed household interviews, 17,967 (51.5%, Row O) had 

adequate vaccination histories based on provider reporting (17,756) or were determined to be 

unvaccinated (211). The other 48.5% of children lacked adequate provider data for a variety of 

reasons, such as the parent did not give consent to contact the child’s provider(s), the provider(s) 

did not have records for the child, or the provider(s) did not report the vaccination history. For each 

estimation area and each state, Table F.1 (see Appendix F) shows the number of children with completed 

household interviews and the number of children with adequate provider data. The percentage of 

children with adequate provider data varied among the non-territory estimation areas from 41.1% 

in Mississippi to 63.1% in Utah. Among the U.S. territories, the percentages were 31.1% in Puerto 

Rico, 42.6% in the U.S. Virgin Islands, and 45.7% in Guam. 

The phrase “adequate provider data” originally meant that sufficient vaccination history information was 

obtained from the provider(s) to determine whether the child is up-to-date with respect to the 

recommended vaccination schedule. Starting with the 2002 NIS-Child public-use data file, the definition 

of children with adequate provider data was expanded to include unvaccinated children. These are 

children for whom either (1) the respondent reported during the household interview that the child had 

received no vaccinations and has no providers, or (2) the respondent reported during the household 

interview that the child had received no vaccinations but has one or more providers, and those providers 

all reported administering no vaccinations. An NCHS Series 2 Report on the statistical methodology of 

the NIS-Child (Smith et al. 2005) includes details of how unvaccinated children are included in the 

estimates of vaccination coverage. This report can be viewed at
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 12

http://www.cdc.gov/nchs/data/series/sr_02/sr02_138.pdf. This modification to the NIS-Child produces 

only small changes in vaccination coverage for estimation areas and states, because the number of 

unvaccinated children in the sample is very small (only 224 in 2021, including the U.S. territory 

samples). As described in the introduction, the definition of adequate provider data was modified in 2012 

to include all children with provider-reported vaccination data, plus unvaccinated children. 

In 2021, data from the Health Insurance Module (HIM) were collected. Among the 34,863 children 

with completed household interviews, 22,002 (63.1%, Row P) completed the HIM. 

2.4. Informed Consent, Security, and Confidentiality of Information

The introduction to the telephone survey and oral consent assure the respondent of the confidentiality of 

his/her responses and the voluntary nature of the survey. Informed consent is obtained from the person in 

the household most knowledgeable about the eligible child’s vaccination history (generally the parent or 

guardian of the child). Informed consent to contact the child’s vaccination provider(s) is obtained at the 

end of the interview.

Information in the NIS-Child is collected and processed under high security. To ensure privacy of the 

respondents and confidentiality of sensitive information, standards have been established for release of 

data from this survey. All CDC staff and contractor staff involved with the NIS-Child sign confidentiality 

agreements and follow instructions to prevent disclosure.

All information in the NIS-Child is collected under strict confidentiality and can be used only for research 

[Section 308(d) of the Public Health Service Act, 42 U.S. Code 242m(d) and the Privacy Act of 1974 (5 

U.S. Code 552a)]. Prior to public release, the contents of the public-use data file go through extensive 

review by the NCIRD Disclosure Review Board to protect participant privacy as well as data 

confidentiality.
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Table 1: Selected Operational Results of Q1/2021-Q4/2021 NIS-Child Data Collection 

(Excluding U.S. Territories) 

Row Key Indicator 

 

Cellular Phone Sample Formula 

Number Percent 

Household Phase

A Total Selected Telephone Numbers in Released Replicates 19,630,940 -- -- 

B Phone Numbers Resolved before Computer-Assisted Telephone Interviewing 54,719 0.3% B/A 

C Total Phone Numbers Released to Telephone Centers 19,576,221 -- A-B 

D Advance Letters Mailed 0 0.0% D/C

E Resolved Phone Numbers1 – Resolution Rate 7,735,672 39.4% E/A

F Households Identified – APCN Rate2 1,650,700 21.3% F/E

G Households Successfully Screened3 – Screener Completion Rate 1,395,556 84.5% G/F

H Eligible Households – Eligibility Rate4 48,887 3.5% H/G

I Households with Completed Household Interviews – Interview Completion Rate 33,647 68.8% I/H 

J CASRO5 Response Rate6 -- 22.9% -- 

K Age-Eligible Children with Completed Household Interviews7 34,863 -- -- 

Provider Phase

L Children with Consent to Contact Vaccination Providers 21,408 61.4% L/K

M Immunization History Questionnaires Mailed to Providers 25,309 -- -- 

N Immunization History Questionnaires Returned from Providers 22,970 90.8% N/M

O Children with Adequate Provider Data

17,967 

(includes 211 

unvaccinated 

children) 

51.5% O/K

Modules

P Age-Eligible Children with Completed Household Interview and Completed 

Health Insurance Module 22,002 63.1% P/K

1 Includes phone numbers resolved before computer-assisted telephone interviewing (CATI (Row B)). 

2 Active personal cellular phone number (APCN) rate.

3 The household screener screens for non-minor-only cellular phone households with age-eligible children.

4 Of the screened households, the proportion that were non-minor-only cellular phone households with age-eligible children.

5 CASRO, Council of American Survey Research Organizations.

6 The response rate is the number of households with a completed household interview divided by the estimated number of eligible 

households in the sample. The number of eligible households in the sample was estimated using the CASRO assumptions; these 

assumptions are that the rate of households among the unresolved telephone numbers is the same as the observed rate of households among 

the resolved telephone numbers, and the rate of eligible households among unscreened households is the same as the observed rate of 

eligible households among screened households. Under these assumptions, the CASRO response rate is equal to the product of the 

resolution rate, the screener completion rate, and the interview completion rate. 

7 Rows K-P reflect the removal of children with a completed interview that were later found to be ineligible based on post-survey data 

cleaning operations.
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3. Content of NIS-Child Questionnaires 

This section describes the questionnaires used in the 2021 NIS-Child telephone interview of households 

and Provider Record Check. 

3.1. Content of the Household Questionnaire 

The computer-assisted telephone interview (CATI) questionnaire used in the RDD phase of NIS-Child

data collection consists of two parts: a screener to identify households with children aged 19 through 35 

months and an interview portion. The questionnaire is modeled on the Immunization Supplement to the 

National Health Interview Survey (NHIS) (NCHS 1999). The NIS-Child CATI questionnaire has been 

translated into Spanish, and LanguageLine Solutions® (formerly part of AT&T) is used for real-time 

translation into many other languages (Wall et al. 1995). Table 2 summarizes the content of each section 

of the NIS-Child household interview. The CATI questionnaire is available at

http://www.cdc.gov/vaccines/imz-managers/nis/datasets.html.

In the screener, the purpose of the survey is explained to the respondent, and the household is screened to 

determine whether it contains any children aged 19 through 35 months (any child who was or would be 

aged 19 through 35 months during the calendar quarter is eligible). If the household has an eligible child, 

the respondent is asked whether he/she is the most knowledgeable person for the child’s vaccination 

history. If the respondent indicates that another person in the household is more knowledgeable, the 

interviewer asks to speak to him/her at that time. If that person is unavailable to be interviewed, the 

interview proceeds to Section MR, the name of the most knowledgeable person is recorded, and a 

“callback” is scheduled for a later date. Prior to screening for age-eligibility, the household is screened to 

ensure that the cellular phone is used by an adult (i.e., to ensure it is not a minor-only cellular phone). If 

the household has more than one age-eligible child, data are collected for each eligible child. 
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Table 2: Content of the Household Interview, National Immunization Survey - Child, 2021 

Questionnaire 

Section Content of Section

Section S Screening questions to determine NIS-Child eligibility

Section MR Most-knowledgeable-respondent callback questions

Section B Ever vaccinated and influenza vaccination questions

Section C Demographic and socioeconomic questions

Section D Provider information and request for consent to contact the eligible child’s vaccination 

provider(s)

Section E Health Insurance Module (HIM)

Prior to Q1/2012, the person being interviewed was asked during the screener section whether he/she had 

a written record (shot card) of the child’s vaccination history and whether it was easily accessible. If a 

shot card was available, the respondent was asked to provide information directly from it in Section A

(which asked respondents with shot cards about the shots on the card). However, beginning in Q1/2012, 

Section A and most of Section B were eliminated from the regular questionnaire, and therefore all 

interviews proceeded directly to a reduced form of Section B, which asks the respondent to recall 

information about the child’s influenza vaccinations. In 2015 and 2016, Section A was reinstated for 

Guam respondents, but was discontinued for all respondents beginning in 2017.

Section C obtains information that includes relationship of respondent to the child, race and Hispanic 

origin of the child, household income, educational attainment of the mother, and other information on the 

socioeconomic characteristics of the household and its eligible children. 

In Section D of the NIS-Child household interview, identifying information (such as name, address, and 

telephone number) for the child’s vaccination provider(s) is requested, as well as the full names of the 

child(ren) and the respondent, so that NIS-Child personnel can contact the provider(s) and identify the 

child(ren) whose immunization information the NIS-Child is requesting. After this information is 

obtained, consent to contact the child’s vaccination provider(s) is requested. When oral consent and 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 16

sufficient identifying information are obtained, the immunization history questionnaire is mailed to the 

child’s vaccination provider(s). 

Beginning in 2006, a Health Insurance Module (HIM) was administered upon completion of Section D to 

collect data regarding the types of medical insurance coverage the child has had since birth. If a 

respondent provided consent to contact medical providers and completed Section D, he/she flowed 

directly into the HIM. If, however, consent or any other critical provider question was refused, the call 

was terminated; only upon callback on which consent was granted or a second refusal given within 

Section D was the respondent asked the HIM. 

One change was made to the NIS-Child questionnaire for 2021: 

• Income questions were updated to refer to the previous year, 2020. That is, the question text 

at CFAMINC, C12_DONT_KNOW, and C12_REFUSED was updated to ask about 2020

income rather than 2019 income. 

3.2. Content of the Immunization History Questionnaire (IHQ)

The immunization history questionnaire mailed to the vaccination providers is designed to be simple and 

brief, to minimize provider burden and encourage survey participation. The structure and content of this 

form were initially derived from the National Immunization Provider Record Check Study 

(NHIS/NIPRCS), which collected and reconciled vaccination data from the providers of respondents to 

the Immunization Supplement to the National Health Interview Survey. The immunization history 

questionnaire consists of two double-sided pages. Page 1 includes space for a label that gives the child’s 

name, date of birth, and sex. The remainder of page 1 contains questions about the facility and 

vaccination provider. Page 2 gives instructions for filling out the shot grid, which appears on page 3. Page 

4 thanks the vaccination provider for providing the information, and lists websites and telephone numbers 

that can be used to obtain more information about the NIS-Child and the NCIRD. The Immunization 

History Questionnaire is available at http://www.cdc.gov/vaccines/imz-managers/nis/datasets.html. 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 17

Since 2015, a Spanish-translated version of the NIS-Child IHQ has been used for Puerto Rico. This 

version differs slightly from the IHQ used for other estimation areas in that it does not contain the 

response options for Indian Health Service and Pharmacy at Question 5b.

One change was made to the NIS-Child IHQ for 2021: 

• A new DTaP-IPV-Hib-HepB combination shot type box was added to the HepB, DTaP, Hib, 

and IPV sections of the IHQ shot grid, and shot type boxes for HepB-Hib, DTaP-Hib, and 

Hib-GSK were removed. 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 18

4. Data Preparation and Processing Procedures 

The household and provider data collection in the NIS-Child incorporate extensive data preparation and 

processing procedures. During the household interview, the CATI system supports reconciliation of 

critical errors as interviewers enter the data. After completion of interviewing for a quarter, post-CATI 

editing and data cleaning produce a final interview data file. The editing of the provider data begins with 

a manual review of returned immunization history questionnaires, data entry of the questionnaires, and 

cleaning of the provider data file. After the provider data are merged with the household interview data 

and responses from multiple providers for a child are consolidated into a child-level data record, the 

editing continues. A quality assurance check is performed based on the name, sex, and date-of-birth 

information from all sources to ensure that the provider completed the questionnaire for the correct child 

and to confirm age-eligibility. Editing of the provider-reported vaccination dates then attempts to resolve 

specific types of discrepancies in the provider data. The end product is an analytic file containing 

household and provider data for use in estimating vaccination coverage.

4.1. Data Preparation

The editing and cleaning of NIS-Child data involve several steps. First, the CATI system enables 

interviewers to reconcile potential errors while the respondent is on the telephone. Further cleaning and 

editing take place in a post-CATI clean-up stage, involving an extensive review of data values, cross 

tabulations, and the recoding of verbatim responses for race and ethnicity. The next step involves the 

creation of numerous composite variables. Provider data are cleaned in a separate step. After these steps 

have been completed, imputations are performed for item non-response on selected variables, and weights 

are calculated. The procedures and rules of the National Health Interview Survey serve as the standard in 

all stages of data editing and cleaning (http://www.cdc.gov/nchs/nhis.htm). 
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4.1.1. Editing in the CATI System 

The CATI software checks consistency across data elements and does not allow interviewers to enter 

invalid values. Catching potential errors early increases the efficiency of post-survey data cleaning and 

processing.

To prevent an overly complicated CATI system, out-of-range and inconsistent responses produce a 

warning screen, allowing the interviewer to correct real time errors. This allows the interviewer to 

reconcile errors while respondent is on the telephone. CATI warning screens focus on items critical to the 

survey, such as those that determine a child’s eligibility (e.g., date of birth). 

A CATI system cannot simultaneously incorporate every possible type of error check and maximize 

system performance. To reconcile this trade-off, post-CATI edits are used to resolve problems that do not 

require access to the respondent, as well as unanticipated logic problems that appear in the data.

4.1.2. Post-CATI Edits

The post-CATI editing process produces final, cleaned data files for each quarter. The steps in this 

process, implemented after all data collection activities for a quarter are completed, are described below.

Initial Post-CATI Edits and File Creation

After completion of interviewing each quarter, the raw data are extracted from the CATI data system and 

used to create two files: the sample file and the interview data file. The sample file contains one record for 

each sample telephone number and summary information for telephone numbers and households. The 

interview data file contains one record for each eligible sampled child and all data reported for the child

during the household survey. 

Following creation of these two files, a preliminary analysis of each file identifies out-of-range values and 

extraneous codes. The first check verifies the eligibility status of children. Once the required corrections 

are verified, invalid values are replaced with either an appropriate data value or a missing value code. 
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Frequency Review

After the pre-programmed edits are run, frequency distributions of all variables in each file are produced 

and reviewed. Each variable’s range of values is examined for any invalid values or unusual distributions.

If blank values exist for a variable, they are checked to see whether they are allowable and whether they 

occur in excessive numbers. Any problems are investigated and corrected as appropriate. 

File Crosschecks

Crosscheck programs ensure that cases exist across files in a consistent manner. Specifically, checks 

ensure that each case in the interview data file is also present in the sample file and that each case in the 

sample file was released to the telephone center. Checks also ensure that no duplicate households exist in 

the sample file and no duplicate children exist in the interview data file. 

When all checks have been performed, the final quarterly interview data file is created. Programmers and 

statisticians then create composite variables constructed from basic variables for each child. Sampling 

weights (described in Section 6 of this Guide) are added to each record.

4.1.3. Editing of Provider Data 

Six to eight weeks after the close of household data collection for a quarter, the majority of the

immunization history questionnaires have been collected from providers. The data from the hard-copy 

questionnaires are entered and independently re-entered to provide 100% verification. The provider data 

file is cleaned, in a similar fashion to the household data file, for out-of-range values and consistency. A 

computer program back-codes “other shot” verbatim responses into the proper vaccine category (e.g., 

Engerix B counts as Hep B, and Tetramune counts as DTP and Hib). These translations come from a file 

that contains all such verbatim responses ever encountered in the NIS-Child. Also, the provider data file is 

checked for duplicate records, and exact duplicates are removed. If the provider data contain a date of 

birth, sex, or name for the child that differs from the household interview for that child, the questionnaire

is re-examined to see whether it may have been filled out for the incorrect child. Provider data that appear 

to have been filled out for the wrong child are removed from the provider database. When a child has data 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 21

from multiple providers, decision rules are applied to produce the most complete picture of the child’s 

vaccination history. 

Once these data have been cleaned, they are combined with the household data file. Information from up 

to five providers can be added to a child’s record. If more than one provider reported vaccination data for 

the child, the data from the multiple provider reports are combined into a single history for the child, 

called the “synthesized provider-reported vaccination history.” The determination of whether the child is 

up-to-date for recommended vaccines and vaccine series is based on the child’s synthesized providerreported vaccination history.

Many variables in the household data file are checked against or verified with the provider data file. For 

example, a child’s date of birth as recorded by the provider is checked against the date of birth as given 

by the household, to verify that the provider was reporting for that specific child and to form a “best” date 

of birth for the child. All children with at least one provider-reported vaccination are considered to have 

adequate provider data.

4.2. Limitations of Data Editing Procedures

Although data editing procedures were used for the NIS-Child, the data user should be aware that some 

inconsistent data might remain in the public-use data file. The variables that indicate whether a child is 

up-to-date on each vaccine or series (on which the estimates of vaccination coverage are based) are 

derived from provider-reported data, and the NIS-Child does not re-contact households or providers to 

attempt to reconcile potential discrepancies in provider-reported vaccination dates or to resolve date-ofbirth reporting errors. However, beginning with the 1999 NIS-Child, the provider-reported data are 

manually reviewed and edited to correct specific reporting errors. The National Immunization Survey: 

Guide to Quality Control Procedures (CDC 2002) discusses the change in editing procedures in more 

detail. Some children with adequate provider data may have incomplete vaccination histories. These 

incomplete histories arise from three primary sources: 1) the household does not identify all vaccination 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 22

providers, 2) some but not all providers respond with vaccination data, and 3) all identified providers 

respond with vaccination data but fail to list all the vaccinations in the child’s medical record. Even with 

these limitations, the NIS-Child overall is a rich source of data for assessment of up-to-date status and 

age-appropriate vaccination. Also, the NIS-Child is the only source to provide comparable providerreported vaccination data across states and local areas in the United States. 

4.3. Variable-Naming Conventions

The names of variables follow a systematic pattern as much as possible. The codebook for the public-use 

data file groups the variables into ten broad categories according to the source of the data (household or 

provider) and the content of the variable (NCIRD 2022). See Section 7 of this report for detailed 

information on the contents of the public-use data file.

4.4. Missing Value Codes

Missing value codes for each variable can be found in the codebook (NCIRD 2022). For household 

variables, the missing value codes usually are 77 for DON’T KNOW and 99 for REFUSED. Some 

household variables may also contain blanks, if the question was not asked. The variables developed from 

the immunization history questionnaire generally do not have specific missing value codes.

4.5. Imputation for Item Non-Response

The NIS-Child uses imputation primarily to replace missing values in the socioeconomic and 

demographic variables used in weighting. Missing values of these variables are imputed for all children 

with a completed household interview – i.e., all children appearing on the public-use data file. Missing 

values of health insurance variables are also imputed for children with adequate provider data. A 

sequential hot-deck method is used to assign imputed values (Ford 1983). Class variables are used to 

separate respondents into cells. Donors and recipients must agree on the categories of the class variables, 

which include the estimation area. Within the categories of the class variables, respondents are sorted by 

variables related to the variable to be imputed. The last case with an observed value is used as the donor 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 23

for up to four recipients. The “Notes” line for each variable in the codebook (NCIRD 2022) identifies 

variables that contain imputed values. These variables include the sex, Hispanic origin, race, health 

insurance status, and first-born status of the child; the education level, age group, marital status, and 

mobility status of the mother; and the income-to-poverty ratio of the household. 

The count of vaccinations for a specific vaccine is based on the number of unique vaccination dates

reported by the child’s provider(s). In filling out the immunization history questionnaire a provider may 

not know the date of the first dose of hepatitis B, which is typically given at birth. The provider does, 

however, have the option of checking the “Given at Birth” box for the first dose of hepatitis B. If it was 

checked “yes” and the date of the birth dose of hepatitis B was not reported, a program assigns the date of 

the birth dose for this vaccine. A value is imputed from the distribution of provider-reported dates for the 

birth dose of hepatitis B. The birth dose for this imputation is defined as being given in the first 7 days of 

life - between the date of birth (i.e., 0 days) and the date of birth plus 6 days. This imputation procedure 

was first implemented in 2000. For 2021 (excluding U.S. territories), a total of 89 children had the 

date of the birth dose of hepatitis B assigned using the above procedure (see HEP_FLAG).

Table 3 shows the observed distribution of age in days at the birth dose of hepatitis B for children in 2021

with a provider-reported birth dose. A similar table is included in the 2000-2020 data user’s guides. For 

1997, 1998, and 1999, Section 5 of the data user’s guide provides information on the distribution of age in 

days for the birth dose of hepatitis B vaccine and gives guidance on imputing age in days at birth dose for 

children with a missing date, but for whom the provider checked the box indicating that a dose was 

administered at birth (see HEP_BRTH).
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 24

Table 3: Distribution of Age (in Days) at the Birth Dose of Hepatitis B Vaccine, National 

Immunization Survey - Child, 2021 

Age in Days at 

Birth Dose

Unweighted Percentage 

Of Birth Doses*

0 67.9 

1 24.0 

2 4.4 

3 1.4 

4 0.9 

5 0.8 

6+ 0.7 

* Excludes U.S. territories. 

4.6. Vaccine-Specific Recoding of Verbatim Responses

On the IHQ, providers can list vaccinations in the “other” section of the IHQ shot grid. After data 

collection, they are reclassified into the listed categories, if possible, using a vaccination recoding table.

This table is reviewed by NCIRD personnel to ensure the shots are recoded into the appropriate category 

or categories (for combination shots).

4.7. Composite Variables

A number of composite variables (constructed from basic variables) are created and included in the NISChild public-use data file. Composite variables assist users and data analysts by eliminating duplication of 

effort and making NIS-Child data easier to use. 

Since the initial years of NIS-Child data collection, the household composite variables have included upto-date status on individual vaccinations, race of child, household income, and up-to-date status on 

several vaccination series. Many of these household composite variables are included in the NIS-Child

public-use data file. See Section 7 of this report for information on the key variables. 

In Quarter 3, 1999, the NIS-Child race questions (see questions C3, C9 and C10 in the household 

questionnaire) were expanded to include Alaska Native, Native Hawaiian, and Pacific Islander, 

implementing the revised Office of Management and Budget (OMB) standards for classification of race 
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and ethnicity (https://www.whitehouse.gov/wp-content/uploads/2017/11/Revisions-to-the-Standards-forthe-Classification-of-Federal-Data-on-Race-and-Ethnicity-October30-1997.pdf). The composite race 

variables in the 2002 through present NIS-Child public-use data files, however, contain only three 

categories: white alone; black alone; and all other races alone/multiple races. (The variable RACE_K 

classifies each child into one of these three categories, while the variable RACEETHK includes a separate 

“Hispanic” category.) The “all other races alone” category includes Asian, American Indian or Alaska 

Native, Native Hawaiian or Pacific Islander, and other races. If more than one race was selected during 

administration of the child race questions, the child is classified as multiple races. Because of small 

sample sizes and risk of disclosure within estimation areas, the NIS-Child public-use data files do not 

contain any variables with separate multiple-race categories. Rather, the children with multiple races are 

included in the “all other races” category. Table 4 shows some characteristics of the current race/ethnicity 

categories.
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Table 4: Weighted Distribution of Children by Race/Ethnicity and Corresponding Combined Vaccine Series* (4:3:1:3*:3:1:4), 

Pneumococcal, and Varicella Vaccination Coverage Estimates, National Immunization Survey - Child, 2021 

Race/Ethnicity Classification

Weighted Distribution of 

Children aged 19-35 

Months in U.S.

Estimate (%)

Weighted Percentage 

4:3:1:3*:3:1:4 UTD

Estimate (%)

(Standard Error (%))

Weighted Percentage 4+ 

Pneumococcal

Estimate (%)

(Standard Error (%))

Weighted Percentage 1+ 

Varicella at 12+ Months

Estimate (%)

(Standard Error (%))

Hispanic 27.7 71.1 (1.5) 84.6 (1.2) 90.5 (1.0) 

Non-Hispanic white only 44.5 74.2 (0.9) 86.3 (0.7) 93.1 (0.5)

Non-Hispanic black only 13.1 64.7 (2.2) 78.0 (1.9) 88.5 (1.6)

Non-Hispanic American Indian 

or Alaska Native only 0.9 60.7 (5.8) 70.1 (5.5) 94.3 (1.9)

Non-Hispanic Asian only 6.1 76.1 (2.9) 87.4 (2.4) 91.9 (2.2)

Non-Hispanic Native Hawaiian 

or Pacific Islander only 0.2 65.5 (9.9) 81.5 (7.1) 90.4 (6.2)

Multiple races 7.5 74.8 (2.1) 85.5 (1.7) 91.5 (1.2)

Non-Hispanic white/black 3.5 72.1 (3.4) 83.9 (3.0) 90.5 (2.1)

Non-Hispanic white/ American 

Indian or Alaska Native 0.7 62.5 (6.5) 72.2 (6.6) 89.1 (3.5)

Non-Hispanic white/Asian 1.8 82.6 (2.7) 92.1 (1.7) 95.2 (1.3)

Non-Hispanic other combination 1.5 77.6 (4.7) 87.4 (3.1) 90.3 (2.8)

Note: UTD = up-to-date. Weighted by PROVWT_C. Children with an unknown Hispanic origin and/or race were imputed by a hot-deck method. This table excludes U.S. 

territories. 

* 4+ diphtheria and tetanus toxoids and acellular pertussis vaccine adsorbed, diphtheria and tetanus toxoids and pertussis vaccine, or diphtheria and tetanus toxoids vaccine 

adsorbed (DTaP/DTP/DT); 3+ poliovirus vaccine; 1+ measles-containing vaccine (MCV); full series Haemophilus influenzae type b conjugate vaccine (Hib), i.e., 3 or 4 doses 

depending on type of vaccine received; 3+ hepatitis B vaccine (Hep B); 1+ varicella at or after 12 months of age; and 4+ pneumococcal conjugate vaccine (PCV). 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 27

4.8. Subsets of the NIS-Child Data

The NIS-Child public-use data file contains data for all eligible children who have a completed household 

interview. An interview is considered complete if the respondent completed Section C of the 

questionnaire. As explained in Section 6 of this guide, each child with a completed household interview is 

assigned a weight (RDDWT_C for the United States, excluding U.S. territories; RDDWT_C_TERR for 

the United States, including U.S. territories) for use in estimation.

The NIS-Child uses the synthesized provider-reported vaccination histories to form the estimates of 

vaccination coverage because the provider data are considered more accurate than household-reported 

data. Thus, the most important subset of the data consists of children with adequate provider data. For 

these children, one or more providers returned an immunization history questionnaire that included 

vaccination data. Unvaccinated children are also considered to have adequate provider data. As discussed 

in Section 7 below, the PDAT variable identifies the children with adequate provider data (PDAT=1).

These children have a separate weight (PROVWT_C for the United States, excluding U.S. territories; 

PROVWT_C_TERR for the United States, including U.S. territories), which should be used to form 

estimates of vaccination coverage (see Section 6).

4.9. Confidentiality and Disclosure Avoidance

To prevent identification of participants in the NIS-Child and the resulting disclosure of information, 

certain items from the questionnaires are not included in the public-use data file. In addition, some of the 

released variables either are top- or bottom-coded, or have their categories collapsed. Variable labels 

indicate which variables have been re-coded in these ways.
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 28

5. Quality Control and Quality Assurance Procedures 

A major contributor to NIS-Child data quality is its sample management system, which in 2021 managed 

over 230 estimation area by quarter samples and used a number of performance measures to track their 

progress toward completion. Important aspects of the quality assurance program for the RDD component 

of the NIS-Child included interviewer monitoring; on-line provider look-ups in a database system

integrated with the CATI system, including names, addresses, and telephone numbers of vaccination 

providers; and automated range-edits and consistency checks. These and other quality assurance 

procedures contributed to a reduction in total data collection cost by minimizing interviewer labor and 

overall burden to respondents. Khare et al. (2000), Khare et al. (2001), and the National Immunization 

Survey: Guide to Quality Control Procedures (CDC 2002) describe quality assurance procedures. 

The Provider Record Check component used quality control measures at four junctions: prior to mailing 

packets to providers; during the telephone prompting effort; during the editing of returned questionnaires; 

and during and after their data entry. The final quality assurance activities are implemented during postprocessing of the returned questionnaires or vaccination records. All returned questionnaires were

examined to identify and correct any obvious errors prior to data entry and then key-entered with 100% 

verification. The keying error rate is estimated, by way of a second verification process, to be less than 

1%. 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 29

6. Sampling Weights 

Each of the two phases of data collection results in a separate sampling weight for each child that has data 

at that phase. The RDD-phase sampling weights permit analyses of data for children with completed 

household interviews. Each child with adequate provider data (the subset on which official estimates of 

vaccination coverage are based) has a provider-phase sampling weight. The RDD-phase sampling weight

variable for producing estimates for children with completed household interviews in the United States 

excluding U.S. territories is called RDDWT_C; the RDD-phase weight variable for producing estimates 

for the United States including U.S. territories is called RDDWT_C_TERR. The provider-phase 

sampling weight variable for producing estimates for children with adequate provider data in the United 

States excluding U.S. territories is called PROVWT_C; the provider-phase weight variable for producing 

estimates for the United States including U.S. territories is called PROVWT_C_TERR. See Section 8 of 

this user’s guide for more information about the weights included in the data file and the proper way to 

use them.

As discussed below, revisions in weighting methodology were made on various occasions and the names 

of the weight variables were also changed to keep track of the revisions. The RDD-phase sampling 

weights were called HY_WGT in 1995-2001, RDD_WT in 2002, WGT_RDD in 2003- 2004, RDDWT in 

2005-2008, RDDWT/RDDWTVI in 2009-2010, RDDWT_LL/RDDWTVI_LL/RDDWT_D in 2011, 

RDDWT_D/RDDWTVI_D in 2012, RDDWT_D/RDDWTVIGU_D in 2013, 

RDDWT_D/RDDWT_D_TERR in 2014-2016, RDDWT_D in 2017, RDDWT_C in 2018, and 

RDDWT_C/RDDWT_C_TERR in 2019-2021. The provider-phase sampling weights were called W0 in 

1995-2001, WT in 2002, WGT in 2003- 2004, PROVWT in 2005-2008, PROVWT/PROVWTVI in 2009-

2010, PROVWT_LL/PROVWTVI_LL/PROVWT_D in 2011, PROVWT_D/PROVWTVI_D in 2012, 

PROVWT_D/PROVWTVIGU_D in 2013, PROVWT_D/PROVWT_D_TERR in 2014-2016, 

PROVWT_D in 2017, PROVWT_C in 2018, and PROVWT_C/PROVWT_C_TERR in 2019-2021.
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 30

A sampling weight may be interpreted as the approximate number of children in the target population that 

a child in the sample represents. Thus, for example, the sum of the sampling weights of children with 

adequate provider data who are up-to-date (on a particular vaccine or series of vaccines) yields an 

estimate of the total number of children in the target population who are up-to-date. Dividing this sum by 

the total of the sampling weights for all children with adequate provider data gives an estimate of the 

corresponding vaccination coverage rate. 

This section describes how these weights are developed and adjusted so as to achieve an accurate 

representation of the target population. The base weights reflect each telephone number’s probability of 

being selected into the sample; the adjustments take into account non-resolution of residential/nonresidential/non-working status of a telephone number, non-response to the screener and household 

interviews, number of cellular phones used by parents in the household, raking for differential coverage 

rates and non-coverage of households that do not have cellular phones, non-response by providers, and a 

final raking adjustment. 

6.1. Base Sampling Weight

In each quarterly NIS-Child sample, each child with a completed household interview receives a base 

sampling weight. The base sampling weight is equal to the inverse of the probability the phone number 

was sampled from the sampling frame for the quarter and estimation area.

6.2. Adjustments for Non-Resolution of Telephone Numbers, Screener 

Non-Response, and Interview Non-Response 

Non-response occurs in population-based surveys when potential respondents refuse to participate, are not 

available at the time of the interview, or could not be reached during the survey period. Thus, the sum of 

the base sampling weights of children with completed household interviews will underestimate the size of 

the target population in the estimation area, because not all sampled households respond to all stages of 

data collection up to the household interview. As a result, the base sampling weights must be adjusted so 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 31

they accurately reflect the number of children in the target population that each sampled child with a 

completed household interview represents. 

Some sampled households with age-eligible children fail to complete the household interview because of 

unit non-response: for some telephone numbers, it is never determined whether or not the number is a 

working residential number despite multiple call attempts; for some households it is never determined 

whether or not the household contains age-eligible children; and some households with age-eligible 

children do not complete the household interview. To compensate for these three types of unit nonresponse, the sampling weights of children with a completed household interview are adjusted to account 

for the estimated number of age-eligible children in households whose telephone numbers are never 

resolved, the estimated number of age-eligible children in households that fail to complete the screening 

interview, and the number of identified age-eligible children for whom the household interview is not 

completed. Each of these adjustments is carried out within each estimation area by forming weighting 

cells based on the Metropolitan Statistical Area (MSA) status of the wire center associated with the 

cellular phone number (MSA/non-MSA). Each cell in each stage of adjustment must have sufficient 

resolved/responding cases (usually 20, but 15 for interview non-response) at that stage of adjustment. 

The cells with a deficient number of responding cases are collapsed into neighboring cells, i.e., both MSA 

categories are collapsed if either of the cells have a deficient number of responding cases. Once the 

adjustment cells are formed, the weights of the unresolved/non-responding records from the previous 

adjustment step are distributed to the weights of the resolved/responding records within each cell.

6.3. Adjustment for Multiple Cellular Phones and Deriving Annual 

Weights

Once the non-response-adjusted interview weights for households are computed, these weights are 

adjusted for additional cellular phones in the household. Because households with multiple cellular 

phones have a greater chance of being sampled, each child’s household interview weight is adjusted by 

dividing it by the total number of cellular phones used by parents or guardians (up to a maximum of 3).
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 32

Up to the previous step, the sampling weights are adjusted separately for each quarter, and the weights in 

each quarter pertain to the target population. However, annual vaccination coverage estimates are 

obtained from data for four consecutive quarters, so the weights in each quarterly file are adjusted when 

the data from the four quarters are combined. The adjustment factor is proportional to the number of 

households with completed household interviews in each quarter and estimation area. 

6.4. Calibration 

Next, survey weights are calibrated to population control totals as described below. The control totals 

used for the NIS-Child are derived from current natality data from the National Center for Health 

Statistics (NCHS 2018, 2019). Because the Vital Statistics data give the counts of all live births in the 

United States, regardless of whether the household has any cellular phones, the control totals include all 

eligible children. The control total for each raking dimension is derived from the NCHS natality files 

from 2018 and 2019 (children born between July 1, 2018 and November 30, 2019 would have been 

19 through 35 months on June 30, 2021). Use of the natality data to form the required population 

control totals for the NIS-Child has three limitations: 1) the natality file provides a universe of live births 

and therefore does not reflect infant mortality; 2) the natality file does not include children born outside 

the United States who immigrate to this country before reaching ages 19 through 35 months; and 3) the 

natality file records residence at time of birth, and some children may move from one estimation area to 

another by the time they reach 19 through 35 months of age. Adjustments are made to the natality data to 

account for these three factors. For 2021, the combined 2018, 2019, and 2020 one-year American 

Community Survey Public Use Microdata Sample data files were used to make the immigration 

and migration adjustments (U.S. Census Bureau 2019, 2020, 2021). 

Survey weights are adjusted to agree with independent estimates of the population total by telephone 

status. The proportions of 19 through 35 month old children by detailed telephone status (cellular-phoneonly, landline and cellular phone dual user, landline-only, phoneless) within each estimation area were 

derived using a similar small area modeling approach as described in Blumberg et al. (2011). These 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 33

modeled telephone status estimates are applied to the population control total for the estimation area to 

estimate the control totals by detailed telephone status within the estimation area. In each estimation area, 

children in dual landline and cellular phone households are weighted to represent children living in dual 

landline and cellular phone households in the estimation area, and children in cellular-phone-only 

households are weighted to represent children in cellular-phone-only households in the estimation area.

Children in landline-only and phoneless households, which are excluded from the cellular phone sample, 

are accounted for in the raking step described below.

To reduce sampling variability and improve the precision of estimation, extreme weights are trimmed and 

then recalibrated to control totals. RDD sampling weight values exceeding the median weight plus three

times the interquartile range of the weights within an estimation area are truncated and then recalibrated 

to control totals. This is done by up to five iterations. This weight trimming prevents children with 

unusually large weights from having an unusually large impact on immunization coverage estimates.

The final step in adjusting the RDD sampling weights is a raking adjustment (Deming 1943) of the 

trimmed, telephone status adjusted weights. The raking procedure uses estimation area-level control totals 

for maternal education categories, maternal race/ethnicity, age group of the child, sex of the child, and 

telephone status. Briefly, raking takes each variable in turn and applies a proportional adjustment to the 

current weights of the children who belong to the same category of the variable. After a number of 

iterations over all the variables, the raked weights have totals that match all the desired control totals. 

Raking makes it possible to incorporate additional variables into the weighting and to use more detailed 

categories for those variables. Wolter et al. (2017a) gives the details of various aspects of the NIS-Child

estimation procedures.

The sampling weights after all the foregoing adjustments constitute the “RDD sampling weights” 

(RDDWT_C for the United States excluding territories; RDDWT_C_TERR for the United States 

including territories).
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 34

6.5. Adjustment for Provider Non-Response

Among the 34,863 children with a completed household interview (excluding U.S. territories), 

17,967 (51.5%) had adequate provider data. Starting with the 2002 NIS-Child public-use data file, the 

definition of children with adequate provider data includes unvaccinated children. These are children for 

whom the respondent reported during the household interview that the child had received no vaccinations 

and has no providers, or for whom one or more providers were reported but those providers reported 

administering no vaccinations. Among the 17,967 children with adequate provider data, 211 were 

unvaccinated children. Failure to obtain adequate provider data for the remaining 16,896 children (48.5%) 

was attributable to: 

● parent or guardian not identifying any providers or not giving consent to contact the child’s 

vaccination provider(s) (38.2%); 

● consent to contact vaccination providers obtained but no providers returned the immunization 

history questionnaire (6.9%); and

● one or more providers returned the immunization history questionnaire, but no providers reported 

any vaccination data, despite the parent or guardian indicating that the child has received 

vaccinations (3.4%). 

The 16,896 children for whom a household interview was completed but adequate provider data were not 

obtained are classified as “partial non-responders” because they have only a partial response to the NISChild as a whole.

Empirical results suggest that children with adequate provider data have characteristics believed to be 

associated with a greater likelihood of being up-to-date, compared with children who had missing 

provider data. Specifically, children with adequate provider data are more likely to live in households that 

have higher total family income, have a white mother, and live outside a principal city of a Metropolitan 

Statistical Area. Also, a child with missing provider data is less likely to live in the state where the mother 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 35

lived when the child was born. These factors indicate a potential lack of continuity of health care, and are 

associated with lower vaccination coverage (Coronado et al. 2000). If no adjustment is made to the RDD 

sampling weights to account for these differences, estimated vaccination coverage rates may be biased. 

To reduce potential bias in estimators of vaccination coverage attributable to partial non-response, a 

weighting-class adjustment is used in each estimation area (Brick and Kalton 1996). This adjustment 

involves three steps. In the first step, sampled children are classified according to the quintile of their 

estimated probabilities of having adequate provider data. In the statistical literature these probabilities are 

called response propensities (Rosenbaum and Rubin 1983, 1984; Rosenbaum 1987). Children who have 

similar response propensities will also be similar with respect to variables that are strongly associated 

with the probability of having adequate provider data. In this important respect, children in each class are 

comparable. Because of this comparability, any sub-sample of children in a class may represent all 

children in the class. Therefore, the weighting-class adjustment uses the children with adequate provider 

data to represent all children in the class. An NCHS Series 2 Report on the statistical methodology of the 

NIS-Child (Smith et al. 2005) includes details of the methodology for forming weighting classes based on 

propensity scores. This report can be viewed at http://www.cdc.gov/nchs/data/series/sr_02/sr02_138.pdf. 

In the second step of this weighting-class adjustment, within each class an adjustment factor redistributes 

the RDD sample weights of the children with missing provider data to the weights of the children who 

have adequate provider data. These adjusted sampling weights of children with adequate provider data are 

initial non-response-adjusted provider-phase weights. 

Within an estimation area, the sums of non-response adjusted weights of children with adequate provider 

data for the various levels of important socio-demographic variables (such as race/ethnicity) may not be 

equal to corresponding population totals. To reduce bias attributable to these differences, raking was used 

in the third step to adjust the non-response adjusted weights to match estimation area control totals. 

Control totals for these variables were estimated using the weighted totals from the sample of children 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 36

with completed household interviews. Smith et al. (2001b, 2005) describe the development of this 

approach in more detail. Similar to the RDD weighting, the extreme weights exceeding the median weight 

plus three times the interquartile range of the weights within an estimation area are truncated and then 

recalibrated to control totals. These raked weights of children with adequate provider data are called 

“final provider-phase weights” (PROVWT_C for the United States excluding territories and 

PROVWT_C_TERR for the United States including territories). Because of the comparability of 

children within each weighting class, any estimate that uses data only from the children with adequate 

provider data along with their provider-phase sampling weights will have less bias attributable to 

differences between children with adequate provider data and children with missing provider data.

Appendix B summarizes the distribution of the sampling weights (RDDWT_C, PROVWT_C,

RDDWT_C_TERR, and PROVWT_C_TERR) in each estimation area.

NIS-Child public-use data files for 1995 to 2001 do not include sampling weights that account for the 

effect of unvaccinated children. An assessment of the effect of accounting for unvaccinated children for 

the period 1995 to 2003 was made. Weights were calculated for each year with and without unvaccinated 

children and the vaccination coverage estimates compared. Details of this assessment and the results are 

available in the user’s guide for the 2004 NIS-Child public-use data file. At the national level, accounting 

for unvaccinated children had very little effect on the estimates of 4:3:1:3 vaccination coverage. Within 

estimation areas also, the two coverage estimates differed little. The largest difference (in either direction) 

was most often around 2 percentage points. Differences of that magnitude are small relative to the 

standard errors of the estimates. Although accounting for unvaccinated children has a small effect on 

estimates of vaccination coverage, data users who use the pre-2002 public-use data files to examine 

estimation area-level trends over time are advised to interpret the results with appropriate caution.
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 37

6.6. Sampling Weights for Territories

The NIS-Child weighting process was followed as closely as possible for U.S. territories. Due to 

differences in the availability of external data sources for U.S. territories, slight changes were necessary to 

accurately estimate vaccination coverage for these areas. These differences are stated below.

In step 6.2, each of the non-response adjustments for U.S. territories was done at the estimation area level. 

That is, no weighting cells were formed for U.S. territories. 

Similar to the weights for the United States excluding territories, the final step in adjusting the RDD 

sampling weights for U.S. territories is a raking adjustment. For Guam and Puerto Rico, a different set of 

race/ethnicity categories were used for post-stratification and raking adjustments than were used in other 

areas. The three Guam race/ethnicity categories were: Chamorro/Guamanian, Other Asian/Pacific 

Islander, and All Other. The two Puerto Rico race/ethnicity categories were: White and All Other.

After sampling weights were calculated for all children, they were stored in the variables 

RDDWT_C_TERR and PROVWT_C_TERR. These weight variables permit one to conduct analysis 

of all estimation areas, including U.S. territories. The weight variables RDDWT_C and PROVWT_C

are equal to RDDWT_C_TERR and PROVWT_C_TERR for all children except those in U.S. 

territories, for whom the value of these weight variables is blank or missing. RDDWT_C and 

PROVWT_C permit one to conduct analysis of all estimation areas, excluding U.S. territories.
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 38

7. Contents of the Public-Use Data File

The NIS-Child public-use data file contains a record for each eligible child for whom Section C of the 

household interview was completed, along with household-reported information about the child and the 

child’s mother. For children with Immunization History Questionnaires (IHQs) returned by one or more 

providers, the file also contains provider characteristic variables, as well as variables based on the child’s 

synthesized provider-reported vaccination history: the age of the child at each vaccination, the number of 

each type of vaccination received, and indicators of whether the child is up-to-date with respect to various 

recommended vaccines and vaccine series.

The public-use data file consists of ten sections, the contents of which are described below in detail. For 

additional information, users are encouraged to consult the codebook (NCIRD 2022). The codebook is 

divided into the ten sections described below and contains variable names, labels, and response 

frequencies (for categorical variables). For select variables, the codebook also gives additional 

information about the variable in the “Notes” field.

Table 5 lists key NIS-Child variables commonly used in analyses. A full list of variables appearing on the 

2004-2021 NIS-Child public-use data files appears in Appendix E, along with the reason for the addition, 

subtraction, or modification of the variables in 2005-2021. Information on changes made between 1995-

2004 can be found in the Alphabetical Listing of Variables that are Not Available in All Public-Use Data 

Files, National Immunization Survey, 1995-2004. 

http://www.cdc.gov/nchs/data/nis/pufvariables1995to2004.pdf 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 39

Table 5: NIS-Child Variables Commonly Used in Analyses or for Published Estimates

Variable Categories

ID Variables

SEQNUMC – unique child ID variable -

SEQNUMHH – unique household ID variable -

Geographic Variables

ESTIAP21 – estimation area number (introduced in 2021; 

ITRUEIAP used through 2004, ESTIAP in 2005, and ESTIAPyy 

since 2006)

-

STATE – state FIPS code -

CEN_REG – census region

Northeast

Midwest

South 

West

Child Demographic Variables

AGEGRP – age category of child

19-23 months

24-29 months

30-35 months

RACEETHK – race/ethnicity of child

(introduced in 2002; RACEKIDR used in 1995-2001) 

Hispanic

White alone, non-Hispanic

Black alone, non-Hispanic

All other races alone and multiple races, 

non-Hispanic

SEX – sex of child Male

Female

FRSTBRN – firstborn status of the child No

Yes

Mother Demographic Variables

EDUC1 – education of the mother

<12 years

12 years

>12 years, not a college graduate

College graduate

MARITAL2 – marital status of mother

(Living with partner response option added to questionnaire in 

2015)

Currently married

Never married, widowed, divorced, separated, deceased, 

or living with partner

M_AGEGRP2 – age group of mother

(introduced in 2016; M_AGEGRP used through 2015)

<=29 years

30 years or older

Poverty Variables

INCPOV1 – poverty status

(introduced in 2005; INCPOV1R used through 2004)

At or above poverty level, income > $75,000

At or above poverty level, income <= $75,000

Below poverty level

Not determined

INCPORAR – income-to-poverty ratio

(introduced in 2005; INCPORAT used through 2004) -

INCPORAR_I – imputed income-to-poverty ratio

(introduced in 2016) -

WIC Variables

CWIC_01 – child ever participated in WIC program

Yes

No 

Never heard of WIC

Don’t know

Refused 

Missing
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 40

Variable Categories

CWIC_02 – child currently participating in WIC program

Yes

No

Don’t know

Refused 

Missing

Breastfeeding Variables

CBF_01 – child ever fed breast milk

Yes

No

Don’t know

Missing

BF_ENDR06 – length of time in days child was fed breast milk -

BF_EXCLR06 – length of time in days child was exclusively 

fed breast milk or formula (introduced in 2006) -

BF_FORMR20 – age in days when child was first fed formula 

(introduced in 2020; BF_FORMR06 used in 2006 and 2007; 

BF_FORMR08 used 2008-2019)

-

Chicken Pox Variables

HAD_CPOX – did child ever have chicken pox (introduced in 

2005; I_HADCPX used through 2004)

Yes

No

Don’t know

Refused 

Missing

AGECPOXR – age in months when child had chicken pox 

(introduced in 2005; IAGECPXR used through 2004)

0-6 months

7-12 months

13-18 months

19-24 months

25-30 months

31 months or older

Missing

Presence of Provider Data Variables

PDAT – adequate provider data indicator Yes

No

Number of Provider-Reported Doses of Vaccine Variables

P_NUMDTP – total number of DTaP/DTP/DT doses -

P_NUMPOL – total number of polio doses -

P_NUMMMR – total number of MCV doses -

P_NUMHIB – total number of Hib doses -

P_NUMHEP – total number of hepatitis B doses -

P_NUMVRC – total number of varicella doses -

P_NUMPCV – total number of pneumococcal doses -

P_NUMFLU – total number of seasonal influenza doses -

P_NUMHEA – total number of hepatitis A doses -

P_NUMROT – total number of rotavirus doses -

Provider Characteristic Variables

PROV_FAC – provider facility type

All public facilities

All hospital facilities

All private facilities

All military/other facilities

Mixed types

Unknown 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 41

Variable Categories

VFC_ORDER – do child’s providers order vaccines for 

children from state/local health department? (introduced in 

2006)

All providers

Some but not all providers

No providers

Unknown 

REGISTRY – provider(s) reported child’s vaccination(s) to 

state or community immunization registry

All providers

Some but not all providers

No providers

Unknown 

Insurance Status Variables

INS_STAT2_I – child’s current health insurance coverage 

status (introduced in 2017, INS_STAT_I used in 2016)

Private insurance only 

Any Medicaid

Other insurance (CHIP, IHS, military, or some other form 

of insurance, alone or in combination with private 

insurance) 

Uninsured 

INS_BREAK_I – child’s insurance history since birth

(introduced in 2016)

Currently insured but uninsured since birth

Currently insured and never uninsured since birth

Currently uninsured but insured since birth

Currently uninsured and never insured since birth

Before describing the sections of the public-use data file below, we first summarize the differences 

between the 2020 and 2021 NIS-Child public-use data files:

• A new 2021 estimation area variable (ESTIAP21) has been added and the 2020 estimation 

area variable (ESTIAP20) has been dropped. Although data were collected for the U.S. 

Virgin Islands and Guam in 2021, children in these areas are not included on the public-use 

data file to protect confidentiality.

• A new shot counter variable, P_NUMDIHB, was added to the 2021 public-use file to 

indicate the number of shots received in the new DTaP-IPV-Hib-HepB combination shot 

type. 

• In prior years, health insurance variables INS_STAT2_I and INS_BREAK_I were available

only for children with adequate provider data in the non-territory United States. Beginning 

in 2021, these variables are now available for all children with adequate provider data, 

including children in Puerto Rico.
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 42

7.1. Section 1: ID, Weight, and Flag Variables

SEQNUMHH and SEQNUMC are the unique household and child identifiers, respectively. PDAT

indicates which children are considered to have adequate provider data. As described in Section 6 of this 

report, RDDWT_C/RDDWT_C_TERR and PROVWT_C/PROVWT_C_TERR are the final 

household- and provider-phase weights, respectively. PROVWT_C/PROVWT_C_TERR should be 

used when analyzing the provider-reported data, i.e., the variables in Sections 7, 8, and 9 of the NIS-Child

public-use data file.

7.2. Section 2: Household-Reported Vaccination and Chickenpox

Information

Section 2 of the public-use data file contains variables derived from the information collected in Section 

B of the household questionnaire. In particular, it contains variables indicating whether the respondent 

reported that the child has had chicken pox disease (HAD_CPOX) and the child’s age in months at 

chicken pox disease (AGECPOXR).

7.3. Section 3: Demographic, Socio-Economic, and Other 

Household/Child Information

Section 3 of the NIS-Child public-use data file consists of information collected during the household 

screening interview and Section C of the household main interview. To protect confidentiality, many of 

these variables have been collapsed, top-coded, or bottom-coded from the original, fully-detailed 

versions; the variable labels (see the public-use date file codebook) indicate which variables have been 

collapsed or recoded. 

AGEGRP is the age of the child in months in three categories (19-23 months, 24-29 months, 30-35 

months), based on the child’s best date of birth and the eligibility date. SEX gives the sex of the child, 

and FRSTBRN indicates whether the child is the first born, with missing values of these variables 

imputed. The language in which the interview was conducted is stored in variable LANGUAGE, and

C5R gives the relationship of the respondent to the child.
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 43

The breastfeeding variables include whether the child was ever fed breast milk (CBF_01), length of time 

in days the child was fed breast milk (BF_ENDR06), the age in days when the child was first fed formula 

(BF_FORMR20), and the length of time in days the child was exclusively fed breast milk or formula 

(BF_EXCLR06). Two types of inconsistencies arise in the breastfeeding data: 1) duration of any 

breastfeeding can exceed age of the child, and 2) age when the child was first fed formula can exceed the 

age of the child. BFENDFL06 is set equal to 1 when BF_ENDR06 exceeds the age of the child (with a 

buffer), and BFFORMFL06 is set equal to 1 when BF_FORMR20 exceeds the age of the child (with a 

buffer). Appendix C provides details on how the flags were created. Data users are cautioned to review 

Appendix C before analyzing any of the breastfeeding variables.

The WIC variables include whether the child ever participated in the WIC program (CWIC_01) and 

whether the child is currently participating (CWIC_02). 

C1R and CHILDNM give the number of people and children, respectively, in the household. The child’s

Hispanic origin indicator, race with three categories, and race/ethnicity with four categories are presented 

in variables I_HISP_K, RACE_K, and RACEETHK, respectively; for each of these variables, missing 

values have been imputed. The age, education level, and marital status of the mother of the child are 

stored in variables M_AGEGRP2, EDUC1, and MARITAL2 (married vs. not married), with missing 

values imputed. 

The categorized total combined income for the child’s family is given by INCQ298A. INCPOV1 gives 

the family’s poverty status (at or above poverty, income > $75,000; at or above poverty, income <= 

$75,000; below poverty; unknown), and INCPORAR gives the ratio of the family’s income to the 

poverty level. INCPORAR_I gives the same ratio after missing values of family income have been 

imputed. Household tenure is given by RENT_OWN. 

The number of landline telephone numbers in the household, the number of working cellular phones 

household members have available for personal use, and the number of these cellular phones that are 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 44

usually used by parents or guardians are given by NUM_PHONE, NUM_CELLS_HH, and 

NUM_CELLS_PARENTS, respectively.

Variable CEN_REG gives the census region of the respondent’s current residence, and MOBIL_I 

indicates whether the mother’s current state of residence is the same as her state of residence at the time 

of the child’s birth.

7.4. Section 4: Geographic Variables

Variables ESTIAP21 and STATE give the 2021 estimation area and state of residence, respectively, for 

each child. EST_GRANT indicates which of the 50 states, District of Columbia, and 5 local areas that 

receive federal Section 317 immunization awards (Bexar County, TX; City of Chicago, IL; City of 

Houston, TX; New York City, NY; Philadelphia County, PA) the child resides in.

7.5. Section 5: Number of Providers Identified and Consent Variables

Variable D7 indicates whether the respondent gave consent to contact the child’s providers. If D7=1, then 

consent was granted; if D7=2 then consent was explicitly denied; and if D7 is missing, consent was not 

granted because the respondent broke off the interview before being explicitly asked for consent. 

Variable D6R gives the number of providers identified by the respondent. Note that sometimes 

respondents report erroneous provider counts and sometimes report the same provider more than one 

time, and D6R does not reflect cleaning or de-duplication of the initially-reported provider count.

7.6. Section 6: Number of Responding Providers Variables

Variable N_PRVR indicates the number of providers returning IHQs with vaccination information for the 

child. That is, N_PRVR is the number of IHQs that were returned for the child that contain information 

on the IHQ shot grid. 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 45

7.7. Section 7: Characteristics of Providers Variables

The variables in this section of the public-use data file summarize the information collected in IHQ 

questions 5b, 6, and 7 across the child’s providers who returned IHQs containing vaccination (i.e., shot 

grid) data.

PROV_FAC indicates the facility type of the child’s vaccination providers based on responses to IHQ 

question 5b. If all of the child’s providers that returned IHQs containing shot grid data (see Section 6 

variable N_PRVR) reported the facility type to be:

● a public health department-operated clinic, community health center, or rural health clinic, then 

PROV_FAC=1 (all public facilities);

● a hospital-based clinic, then PROV_FAC=2 (all hospital facilities);

● a private practice, then PROV_FAC=3 (all private facilities); 

● a military health care facility, WIC clinic, school-based health center, pharmacy, or other type of 

facility, then PROV_FAC=4 (all military/WIC/school/pharmacy or other facilities).

If the responses of providers that returned IHQs containing shot grid data fell into more than one of the 

above bulleted categories, PROV_FAC=5 (mixed); otherwise, if at least one of the child’s providers 

returned an IHQ containing shot grid data, PROV_FAC=6 (unknown). If none of the child’s providers 

returned an IHQ containing shot grid data, PROV_FAC is set to missing.

The Vaccines For Children (VFC) program is a federally-funded program that provides vaccines at no 

cost to children who might not otherwise be vaccinated because of inability to pay

(http://www.cdc.gov/vaccines/programs/vfc/index.html). CDC buys vaccines at a discount and distributes 

them to awardees—i.e., state health departments and certain local and territorial public health agencies—

which in turn distribute them at no charge to those private physicians’ offices and public health clinics 

registered as VFC providers. VFC_ORDER, based on responses to IHQ question 6, indicates whether the 

child’s vaccination providers order vaccines from a state or local health department to administer to 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 46

children. If all of the child’s providers that returned IHQs containing shot grid data (see Section 6 variable 

N_PRVR) reported that they order vaccines from a state or local health department to administer to 

children, then VFC_ORDER=1 (all providers); if at least one of the child’s providers that returned an 

IHQ containing shot grid data reported that the practice orders vaccines from a state or local health 

department to administer to children and the child’s other providers that returned IHQs containing shot 

grid data reported either that they did not order such vaccines or that they did not know whether or not 

they did, then VFC_ORDER=2 (some but possibly or definitely not all providers); if all of the child’s

providers that returned IHQs containing shot grid data reported that they do not order vaccines from a 

state or local health department to administer to children, then VFC_ORDER=3 (no providers); if none of 

the conditions for VFC_ORDER=1, 2, or 3 were met but at least one of the child’s providers returned an

IHQ containing shot grid data, VFC_ORDER=4 (unknown). If none of the child’s providers returned an 

IHQ containing shot grid data, VFC_ORDER is set to missing. Note that having a provider that orders 

VFC vaccines does not imply that the child is VFC-entitled; providers enrolled in the VFC program could 

also vaccinate children who are not VFC-entitled. 

REGISTRY is based on responses to IHQ question 7 and indicates whether the child’s vaccination 

providers reported the child’s vaccinations to a local or state immunization registry (also known as an 

Immunization Information System, or IIS). If all of the child’s providers that returned IHQs containing 

shot grid data (see Section 6 variable N_PRVR) indicated that they reported to a registry, then 

REGISTRY=1 (all providers); if at least one of the child’s providers that returned an IHQ containing shot 

grid data indicated that the practice reported to a registry and the child’s other providers that returned 

IHQs containing shot grid data indicated that they did not report to a registry, that they did not know 

whether or not they reported to a registry, or that the question is not applicable, then REGISTRY=2 (some 

but possibly or definitely not all providers); if all of the child’s providers that returned IHQs containing 

shot grid data indicated that they did not report to a registry or that the question is not applicable, then 

REGISTRY=3 (no providers); if none of the conditions for REGISTRY=1, 2, or 3 were met but at least 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 47

one of the child’s providers returned an IHQ containing shot grid data, REGISTRY=4 (unknown). If none 

of the child’s providers returned an IHQ containing shot grid data, REGISTRY is set to missing.

7.8. Section 8: Provider-Reported Up-To-Date Vaccination Variables

This section contains vaccination count and up-to-date variables based on the child’s synthesized 

provider-reported vaccination history. To facilitate data processing and to accommodate the large and 

continually growing number of vaccination types covered by the NIS-Child, the provider-reported 

vaccination data are organized around the concept of vaccine categories and vaccine types within vaccine 

category. The vaccine categories correspond to the sections of the IHQ shot grid, and the vaccine types 

correspond to the type boxes on the IHQ shot grid. (For each vaccine category, an “unknown” vaccine 

type is created for vaccinations that are reported without a type box being checked. Also, a few vaccine 

types, such as Measles-Mumps, arise through the backcoding of shots initially reported in the “other” 

section of the IHQ shot grid.) Table 6 shows the vaccine categories and types for the 2021 NIS-Child. 

Note that a single vaccination can fall into more than one vaccine category; for example, an MMRVaricella vaccination is part of both the Measles-containing and Varicella-containing vaccine categories.

(The full list of vaccine type codes can also be found in Appendix H.)

For each vaccine category, Section 8 of the public-use data file contains a variable typically named 

P_NUMYYY – where “YYY” is the vaccine category abbreviation given in Table 6 – that stores the 

number of vaccinations in that vaccine category in the child’s synthesized provider-reported vaccination 

history. For each vaccine type in Table 6, Section 8 also contains a variable that stores the number of 

vaccinations of that vaccine type in the child’s synthesized provider-reported vaccination history. For 

example, P_NUMDHI is the number of DTaP/HepB/IPV shots in the child’s history.

This section of the public-use data file also contains up-to-date indicators for a variety of recommended 

vaccines and vaccine series. These variables’ names typically begin with “P_UTD”. Additional variables 

indicate whether the child is up-to-date for various vaccine series. For example, P_UTD431 indicates 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 48

whether the child has received 4 or more DTaP/DTP/DT shots, 3 or more polio shots, and one or more 

measles-containing shots. The variable labels indicate what is needed to be considered up-to-date for each 

variable, and the “Notes” field in the codebook shows the vaccine type codes (see Table 6) being included 

when determining whether the child is up-to-date.

Note that it is possible that the administration of the NIS-Child interview itself prompts some respondents 

to vaccinate their children following the interview; to ensure that the vaccination coverage estimates are 

not artificially boosted because of this, the synthesized vaccination history count and up-to-date variables 

in this section of the public-use data file count only vaccinations received before the date the household 

interview was completed. Note also that because children are eligible for the NIS-Child if they are 19 to 

35 months old on any day of the survey quarter, some children are less than 19 months old or greater than 

35 months old on the date the household interview is completed. For children with interviews conducted 

before they became 19 months old, the Provider Record Check is not conducted until after the child has 

become 19 months old, and all vaccinations given up to age 19 months are counted, including those given 

after the household interview date. For children with interviews conducted after they became 36 months 

old, only vaccinations given through age 35 months are counted. 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 49

Table 6: Vaccine Categories and Vaccine Types, National Immunization Survey - Child, 2021 

Vaccine Category 

Abbreviation

Vaccination Category 

Description

Vaccine 

Type Code Vaccine Type Description

DTP DTaP/DTP/DTcontaining vaccine

03 DTaP/DTP/DT-containing, unknown type

04 DTaP/DTP/DT

07 DTaP-Hib

08 DTaP-HepB-IPV

D3 DTaP-IPV-Hib

D4 DTaP-IPV-Hib-HepB

POL or POLIO Polio-containing vaccine

08 DTaP-HepB-IPV

20 OPV

21 IPV

22 Polio-containing, unknown type

D3 DTaP-IPV-Hib

D4 DTaP-IPV-Hib-HepB

MCV or MMR Measles-containing 

vaccine

30 MMR

31 Measles only

32 Measles-mumps

33 Measles-rubella

MM Measles-containing, unknown type

VM MMR-Varicella

HIB Hib-containing vaccine

07 DTaP-Hib

43 HepB-Hib

44 Hib-only, unknown type

D3 DTaP-IPV-Hib

D4 DTaP-IPV-Hib-HepB

HG Hib-only (GSK)

HI Hib-containing, unknown type

HM Hib-only (Merck)

HS Hib-only (Sanofi)

HY Hib-MenCY

HEPB or HEP Hepatitis B-containing 

vaccine

08 DTaP-HepB-IPV

43 HepB-Hib

60 HepB-only

D4 DTaP-IPV-Hib-HepB

HB HepB-containing, unknown type

VRC Varicella-containing 

vaccine

VA Varicella-containing, unknown type

VM MMR-Varicella

VO Varicella-only

PCV Pneumococcalcontaining vaccine

70 Conjugate-unknown

71 Polysaccharide

72 Pneumococcal-containing, unknown type

73 Conjugate-7

74 Conjugate-13

HEPA or HEA Hepatitis A-containing 

vaccine HA Hepatitis A

FLU Seasonal influenza 

vaccine

FL Seasonal influenza, unknown type

FM Seasonal influenza spray

FN Injected seasonal influenza

MP Mumps-only vaccine MP Mumps-only

MPRB or MPR Mumps-Rubella-only 

vaccine MB Mumps-Rubella-only

RB Rubella-only vaccine RB Rubella-only
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 50

Vaccine Category 

Abbreviation

Vaccination Category 

Description

Vaccine 

Type Code Vaccine Type Description

ROT Rotavirus-containing 

vaccine

RG Rotarix® (GSK)

RM RotaTeq® (Merck)

RO Rotavirus, unknown type

7.8.1. Hib Up-To-Date Variables 

A Hib vaccine shortage and interim recommendation to suspend the booster dose for healthy children 

occurred December 2007 to September 2009 (CDC 2010). Furthermore, the NIS-Child has historically 

considered children to be up-to-date for Hib if the child had 3 or more doses of any Hib-containing 

vaccine, but for some Hib vaccine product types, 4 doses are required. Because the NIS-Child has 

historically not distinguished between product types for Hib vaccine, children who received 3 doses of a 

vaccine product that required 4 doses were misclassified as up-to-date for Hib (CDC 2010).

Because of the Hib vaccine shortage and because of the dependence of the Hib recommendation on 

product type, in 2009 the IHQ was modified to capture the manufacturer of the Hib vaccinations the child 

has received. Beginning with the 2009 NIS-Child public-use data file, new up-to-date variables were 

added to indicate up-to-date status based on Hib recommendation (i.e., the primary series recommended 

during the shortage vs. the full series) and on the Hib manufacturer.

Table 7 shows the Hib up-to-date variables appearing on the public-use data file beginning in 2009 and

Table 8 shows the up-to-date series variables that include Hib appearing on the public-use-date file 

beginning in 2009: in addition to the existing vaccine series up-to-date variables based on 3+ Hib of any 

type (PUTD4313, PUT43133, PU431331, PU4313313, PU4313314), variables based on the “routine” 

(i.e., full series) Hib recommendations accounting for manufacturer (4+ Hib of any type or 2 Hib of 

Merck types followed by 1 Hib of any type) were added (P_UTD431H_ROUT_S, 

P_UTD431H3_ROUT_S, P_UTD431H31_ROUT_S, P_UTD431H313_ROUT_S, 

P_UTD431H314_ROUT_S). 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 51

Note that for these Hib up-to-date variables that account for the manufacturer, if the manufacturer is 

unknown because the provider failed to check a type box on the IHQ, it has been assumed that the 

manufacturer of the Hib vaccine is not Merck; that is, these variables are based on a “strict” treatment of 

Hib vaccinations of unknown type, erring on the side of classifying the child as not up-to-date.

Table 7: Up-To-Date Variables for Hib, National Immunization Survey - Child, 2009-2021 

Name Description Up-To-Date Criteria

P_UTDHIB Historical UTD flag for Hib. 3+ of any type 

(07,43,44,D3,D4,HG,HI,HM,HS,HY) 

P_UTDHIB_SHORT_S

UTD flag for Hib-shortage (i.e., primary 

series) recommendation, accounting for 

manufacturer. Introduced in 2009.

3+ of any type 

(07,43,44,D3,D4,HG,HI,HM,HS,HY) 

OR

2+ Merck types (HM,43)

P_UTDHIB_ROUT_S

UTD flag for routine (i.e., full series) 

Hib recommendation, accounting for 

manufacturer. Introduced in 2009.

4+ of any type 

(07,43,44,D3,D4,HG,HI,HM,HS,HY) 

OR

2 Merck types (HM,43) followed by 1 of 

any type 

(07,43,44,D3,D4,HG,HI,HM,HS,HY) 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 52

Table 8: Up-To-Date Variables for Vaccine Series Including Hib, National Immunization 

Survey - Child, 2009-2021 

Name Description

PUTD4313 UTD flag for the 4:3:1:3 series using the 3+ any type UTD definition for HIB

P_UTD431H_ROUT_S UTD flag for the 4:3:1:3 series using the routine (i.e., full series) UTD 

definition for HIB

PUT43133 UTD flag for the 4:3:1:3:3 series using the 3+ any type UTD definition for 

HIB

P_UTD431H3_ROUT_S UTD flag for the 4:3:1:3:3 series using the routine (i.e., full series) UTD 

definition for HIB

PU431331 UTD flag for the 4:3:1:3:3:1 series using the 3+ any type UTD definition for 

HIB

P_UTD431H31_ROUT_S UTD flag for the 4:3:1:3:3:1 series using the routine (i.e., full series) UTD 

definition for HIB

PU4313313 UTD flag for the 4:3:1:3:3:1:3 series using the 3+ any type UTD definition for 

HIB

P_UTD431H313_ROUT_S UTD flag for the 4:3:1:3:3:1:3 series using the routine (i.e., full series) UTD 

definition for HIB

PU4313314 UTD flag for the 4:3:1:3:3:1:4 series using the 3+ any type UTD definition for 

HIB

P_UTD431H314_ROUT_S UTD flag for the 4:3:1:3:3:1:4 series using the routine (i.e., full series) UTD 

definition for HIB

7.8.2. Rotavirus Up-To-Date Variables

The up-to-date status for rotavirus vaccine depends on the manufacturer of the vaccines received; the 

requirement is two or more doses of Rotarix® (GSK) or three or more doses of rotavirus vaccine of any 

type. Beginning with the 2009 NIS-Child public-use data file, an up-to-date variable for rotavirus vaccine 

(P_UTDROT_S) was added to indicate up-to-date status, accounting for the manufacturer (3+ rotavirus

doses of any type or 2+ Rotarix® doses). 

Note that for this rotavirus up-to-date variable, if the manufacturer is unknown because the provider failed 

to check a type box on the IHQ, it has been assumed that the rotavirus vaccine dose is not Rotarix®; that 

is, this variable is based on a “strict” treatment of rotavirus vaccinations of unknown type, erring on the 

side of classifying the child as not up-to-date.
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 53

7.9. Section 9: Provider-Reported Age-At-Vaccination Variables

This section contains variables storing the child’s age in days and months at each vaccination in the 

synthesized provider-reported vaccination history, along with the vaccine types of those vaccinations.

For each vaccine category, variables named DYYY1 - DYYY9 and YYY_AGE1 - YYY_AGE9 store the 

age in days and months, respectively, of the child when the vaccination was administered for up to nine 

vaccinations in the child’s synthesized provider-reported vaccination history, where “YYY” is the vaccine 

category abbreviation given in Table 6. For vaccine categories that contain multiple vaccine types, 

variables XYYYTY1 - XYYYTY9 give the corresponding vaccine type code (see Table 6). 

Unlike the vaccination count and up-to-date variables in Section 8 of the public-use data file, the variables 

in Section 9 include vaccinations given both before and after the household interview was completed. If 

desired, users can limit the Section 9 variables to only those before the household interview date by 

examining the corresponding Section 8 “P_NUM” variable and limiting the analysis of the Section 9 

variables to only the first n variables, where n is equal to the number of vaccinations in the vaccine 

category before the household interview date as indicated by the corresponding “P_NUM” variable.

Users of the public-use data file should be aware that the age-at-vaccination variables included in Section 

9 may contain a small number of vaccination ages that are implausible according to the recommended 

immunization schedules (http://www.cdc.gov/vaccines/schedules/hcp/child-adolescent.html). Such ages 

may arise if a medical provider inadvertently records an erroneous vaccination date or if a vaccination 

date is incorrectly transcribed onto an IHQ. The quality control procedures of the NIS-Child address 

implausible ages to every extent possible. Suspicious dates are manually reviewed and corrected if there 

is evidence either from the household interview or from another provider that the date is incorrect. In rare 

cases, however, when there is no further information with which to correct the reported vaccination date, 

the vaccination is treated as having actually occurred and the implausible age at vaccination persists on 

the data file. The data user should consider these issues in deciding how to analyze the NIS-Child data.
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 54

7.10. Section 10: Health Insurance Module Variables

The Health Insurance Module (HIM) (Section E) was introduced in 2006 to gather information on the 

health insurance coverage of the child. HIM data were included in the NIS-Child public-use data file for 

the first time in 2007. Prior to 2016, seven variables containing HIM data were included in the NIS-Child

public-use data file:

● INS_1 – “Is child covered by health insurance provided through employer or union?”;

● INS_2 – “Is child covered by any MEDICAID plan?”;

● INS_3 – “Is child covered by S-CHIP?”;

● INS_3A – “Is child covered by any MEDICAID plan or S-CHIP?”;

● INS_4_5 – “Is the child covered by Indian Health Service, Military Health Care, TRICARE, 

CHAMPUS, or CHAMP-VA?”; 

● INS_6 – “Is child covered by any other health insurance or health care plan?”; and

● INS_11 - “Anytime when child was not covered by health insurance?”

In 2016, these variables were replaced by two health insurance variables, INS_STAT_I and 

INS_BREAK_I, which summarize the child’s health insurance status and history across all of the 

insurance questions listed above, while also incorporating the imputation of missing values and recoding 

of verbatim responses. In 2017, INS_STAT_I was replaced with INS_STAT2_I, which provides a 

different categorization of children with both private and non-private, non-Medicaid insurance.

INS_STAT2_I identifies the child’s current health insurance coverage status. If the child has a form of 

private health insurance and is not covered by any other type of health insurance, he/she is classified as 

(1) Private only. If the child is on any form of Medicaid, alone or in addition to other forms of insurance, 

he/she is classified as (2) Any Medicaid. If the child is not covered by Medicaid but is covered by some 

other type of health insurance (including, but not limited to, CHIP, Indian Health Service, Military Health 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 55

Care, TRICARE, CHAMPUS, or CHAMP-VA), either alone or in combination with private insurance, 

he/she is classified as (3) Other. If the child is not covered by any kind of health insurance, he/she is 

classified as (4) Uninsured. 

INS_BREAK_I describes the child’s coverage history since birth and indicates whether there have been 

any breaks in coverage during this period. A child may be (1) currently insured but uninsured at some 

point since birth, (2) currently insured and never uninsured since birth, (3) currently uninsured but insured 

at some point since birth, or (4) currently uninsured and never insured since birth.

Both of these variables are only available for children with adequate provider data.
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 56

8. Analytic and Reporting Guidelines 

Data from the NIS-Child public-use data file can be used to produce national, state, and estimation-area 

estimates of vaccination coverage for children age 19-35 months surveyed in 2021 using the 

PROVWT_C weight (PROVWT_C_TERR if U.S. territories are to be included). As noted in Section 1 

of this user’s guide, since 2018 vaccination coverage estimates appearing on ChildVaxView and in the 

MMWR are based on a birth-cohort estimation approach. That is, the estimates are derived from the 

combination of 2 or 3 years of NIS-Child surveys (e.g., 2019-2021), and the estimates apply to the 

population of children born in particular years (e.g., 2018 or 2019). Therefore, estimates produced using 

the 2021 public-use file, which are based on 2021 NIS-Child data alone and apply to the population of 19-

35 month old children, will differ from those appearing on ChildVaxView and in the MMWR.

Information in the data file can also be used to calculate standard errors of the vaccination coverage 

estimates that reflect the complex sample design of the NIS-Child. The sample is stratified by the 59 

estimation areas. The stratum identifier (STRATUM) and the coded household identifier (SEQNUMHH) 

are key variables for obtaining standard errors for estimation area, state, and national estimates of 

vaccination coverage rates. The estimation area variable ESTIAP21 defines mutually exclusive and 

exhaustive geographic areas, while STRATUM is a combination of the estimation area variable for that 

year and the sampling frame (since 2018, all sample is from the cellular phone sample frame). 

Demographic and socioeconomic variables in the file can be used to obtain national vaccination coverage 

estimates for sub-groups of the population. Data users should, however, be aware that estimates for such 

sub-groups at the state or estimation area level will generally have large standard errors because of small 

sample sizes. The CDC standard for precision of sub-group estimates is that the ratio of the standard error 

to the estimate should be less than or equal to 0.3, and each analytic cell should contain at least 30 

respondents. 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 57

8.1. Use of NIS-Child Sampling Weights

The 2021 NIS-Child public-use data file contains two sets of child-level weights. The RDDWT_C

variable gives the household-phase weight for all children 19 through 35 months in the United States

excluding territories (RDDWT_C_TERR if territories are to be included). These weights should be used 

to form estimates from children with completed household interviews. The weights reflect the stratified 

sample design and also have been adjusted for unit non-response, for the number of cellular phones in the 

household, for post-stratification to population control totals, and for the exclusion of households without 

cellular phones. 

The weight variables that apply to children with adequate provider data are

PROVWT_C/PROVWT_C_TERR. These weights should be used to form estimates of vaccination 

coverage. Each child with adequate provider data (PDAT = 1) has a positive value for 

PROVWT_C/PROVWT_C_TERR. Starting with the 2002 file, the definition of children with adequate 

provider data was expanded to include unvaccinated children (as discussed in Section 2). Table 9 presents 

a summary of the appropriate weights and stratum variables to use for various types of analyses.

The 2021 NIS-Child public-use data file does not contain any provider-level weights. The NIS-Child does 

not sample providers directly; rather, they are included in the survey through the children they vaccinate. 

A user of the file should not attempt provider-level analyses (e.g., estimate the percentage of providers in 

the United States that are private providers), because the NIS-Child sample was not designed for that 

purpose.
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 58

Table 9: Summary of Weights and Stratum Variables, National Immunization Survey - Child, 

2021 

Weight Variable Population* Sample Frame Strata Stratum 

Variable

RDDWT_C United States excluding 

territories

Single-Frame 

Cellular Phone Estimation Area STRATUM

RDDWT_C_TERR United States including 

territories

Single-Frame 

Cellular Phone Estimation Area STRATUM

PROVWT_C 

United States excluding 

territories, children with 

adequate provider data

Single-Frame 

Cellular Phone Estimation Area STRATUM

PROVWT_C_TERR

United States including 

territories, children with 

adequate provider data

Single-Frame 

Cellular Phone Estimation Area STRATUM

* Each weight will contain a missing value for all records that are not included in the population covered by the 

weight.

8.2. Estimation and Analysis

8.2.1. Estimating Vaccination Coverage Rates

Vaccination coverage rates are ratio estimators, as described in the statistical literature on methods for 

complex sample surveys. Because of the adjustment to the sampling weights for provider-phase nonresponse, statistical analyses require only data from children with adequate provider data (PDAT = 1), 

along with their final provider sampling weights (PROVWT_C/PROVWT_C_TERR). To summarize 

the statistical methodology by which vaccination coverage rates and their standard errors are obtained 

from these data, let Yhij be an indicator, for the jth child with adequate provider data in the ith sampled 

household in the hth stratum of the NIS-Child sampling design, equal to 1 if the child is up-to-date 

according to the provider data and 0 otherwise. Also, let Whij denote the value of 

PROVWT_C/PROVWT_C_TERR for this child. Then, letting and , 

the national estimator of the vaccination coverage rate may be expressed as
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 59

where L denotes the number of strata, nh denotes the number of sampled households containing children 

with adequate provider data in the hth stratum, and mhi denotes the number of age-eligible children with 

adequate provider data in the ith household in the hth stratum. 

Letting L instead denote the number of strata in a state, the above formula can also be used to calculate 

vaccination coverage rates for states (regardless of whether the state contains only one or more than one

stratum). 

8.2.2. Estimating Standard Errors of Vaccination Coverage Rates 

The Taylor-series method can be used to estimate the sampling variance of vaccination coverage rates for 

the overall United States, the individual states, and the estimation areas. Letting , 

, and yields an estimator of the variance of the estimated vaccination 

coverage rate, , equal to

(Wolter, 2007). The standard error is the square root of the variance. The estimation of standard errors for 

estimates of vaccination coverage rates in the NIS-Child can be implemented in specialized statistical 

software such as SUDAAN (Research Triangle Institute 2008), SAS (SAS Institute Inc. 2003), R 

(Lumley, 2022), and Stata (Stata Corporation 2009). Appendix D gives several examples of the use of 

SAS, R, and SUDAAN to estimate vaccination coverage rates and their standard errors for estimation 

areas and states. For all procedures, the option of with-replacement sampling of primary sampling units 

within strata is used, because the sampling fractions for households within an estimation area are all quite 

small. For all estimates, the variable STRATUM is used as the stratum variable and the household 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 60

identifier (SEQNUMHH) is used as the primary sampling unit identifier. The data file should be sorted 

first on STRATUM and then on SEQNUMHH before running the programs for SUDAAN and SAS. 

8.3. Combining Multiple Years of NIS-Child Data

8.3.1. Estimation of Multi-Year Means

With release of the 2021 NIS-Child public-use data file, 26 years of public-use NIS-Child data are now 

available. The precision of estimates of vaccination coverage for sub-domains (e.g., by race/ethnicity of 

child) within estimation areas or states can be improved by combining two or more years of NIS-Child

data. Data users should, however, be aware that estimates from combined years of NIS-Child data 

represent an average over two or more years. Although combining several years of NIS-Child data will 

yield a larger sample size for estimation areas and states, the composition of the population in a 

geographic area may change over time, making interpretation of the results difficult. Furthermore, if 

vaccination administration schedules or vaccination coverage changes over time, the estimate of 

vaccination coverage for the combined time period applies to a hypothetical population that existed at the 

middle of the time period, making interpretation of the results even more difficult. Given the use of 

independent RDD samples in the NIS-Child, it is also possible that a child could appear in more than one 

public-use data file.

To estimate a multi-year mean for a given NIS-Child variable, the weights in each participating file

(RDD-phase weights HY_WGT in 1995-2001, RDD_WT in 2002, WGT_RDD in 2003-2004, RDDWT 

in 2005-2010, RDDWT_D/RDDWT_LL in 2011, RDDWT_D/RDDWTVI_D in 2012, 

RDDWT_D/RDDWTVIGU_D in 2013, RDDWT_D/RDDWT_D_TERR in 2014-2016, RDDWT_D in 

2017, RDDWT_C in 2018, and RDDWT_C/RDDWT_C_TERR in 2019-2021; and provider-phase 

weights W0 in 1995-2001, WT in 2002, WGT in 2003-2004, PROVWT in 2005-2010, 

PROVWT_D/PROVWT_LL in 2011, PROVWT_D/PROVWTVI_D in 2012, 

PROVWT_D/PROVWTVIGU_D in 2013, PROVWT_D/PROVWT_D_TERR in 2014-2016, 

PROVWT_D in 2017, PROVWT_C in 2018, and PROVWT_C/PROVWT_C_TERR in 2019-2021) 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 61

should be divided by the number of years being combined. For example, if data for 2017-2021 for 

children in the United States (excluding territories) with adequate provider data are to be combined, then 

the weights that exclude the territories in the five files – called PROVWT_D in 2017 and PROVWT_C

in 2018-2021 – should be divided by 5 to obtain revised weights, which should be saved as a new 

variable, say NEWWT. It is necessary to use NEWWT in the analysis to obtain correct weighted 

estimates for children aged 19 through 35 months. Furthermore, the child and household ID numbers 

(SEQNUMC and SEQNUMHH) in the files are unique only within a year, not across years. It is 

important for the user to create revised, unique ID numbers when combining data from multiple years. 

The following SAS code can be used:

YRSEQC = 1 * (YEAR || SEQNUMC);

YRSEQHH = 1 * (YEAR || SEQNUMHH); 

YEAR is the 4-digit year variable for the NIS-Child data year (e.g., 2021). 

To produce valid estimates of sampling variability and valid confidence intervals for multi-year coverage 

rates and other multi-year means, it is necessary to use specialized software such as SAS or SUDAAN. 

Beginning in 2005, an important new complication was introduced for variance estimation not 

encountered in previous NIS-Child years, because some traditional estimation areas were removed and 

other new areas were defined and introduced to the survey (see Section 2 above for more information 

about rotating estimation areas). The variance strata for 2004 and all prior years are defined by the 

variable ITRUEIAP, while the variance strata for 2005-2021 are defined by the variables ESTIAP for 

2005, ESTIAP06 for 2006, ESTIAP07 for 2007, ESTIAP08 for 2008, ESTIAP09 for 2009, ESTIAP10

for 2010, STRATUM_D/ESTIAP11 for 2011, and STRATUM for 2012-2021, with STRATUM_D and 

STRATUM being a combination of the estimation area variable for that year and the sampling frame 

(landline or cellular phone). The estimation area variables ITRUEIAP, ESTIAP, and ESTIAP06-
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 62

ESTIAP21 define mutually exclusive and exhaustive geographic areas. However, they are not exactly the 

same areas. For example, Dallas County, TX, was a separate estimation area in 2005-2012, 2016-

2017, and 2019 but not in 2013-2015, 2018, and 2020-2021. Other areas, such as New York City, NY

and rest of New York, are estimation areas in all years, including 2005-2021. 

To make inferences concerning multi-year means, the user must take two actions. First, he/she must 

define and save a new stratum variable with a common name for all years included in the analysis.

Second, he/she must define a common set of estimation domains that can be supported by each of the files 

included in the multi-year analysis. To take these actions, the user should follow the following seven-step 

procedure (or its equivalent):

i. Compute and save the new, common variance-stratum variable for each year participating in the 

analysis. The variable should be defined by the equation

STRATUMV = ITRUEIAP, for children in the 2004 or prior years’ public-use data files

= ESTIAP, for children in the 2005 public-use data file

= ESTIAP06, for children in the 2006 public-use data file

= ESTIAP07, for children in the 2007 public-use data file

= ESTIAP08, for children in the 2008 public-use data file

= ESTIAP09, for children in the 2009 public-use data file

= ESTIAP10, for children in the 2010 public-use data file

= STRATUM_D if using PROVWT_D or

ESTIAP11 if using PROVWT_LL, for children in the 2011 public-use data file

= STRATUM, for children in the 2012-2021 public-use data files 

ii. Compute and save the new, common weight variable, NEWWT, as instructed above for each 

year participating in the analysis.

iii. Compute and save the new, unique child and household identification numbers, YRSEQC and 

YRSEQHH, as instructed above for each year participating in the analysis.
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 63

iv. Compute and save a variable defining the common estimation domains to be studied for each year 

participating in the analysis. For example, one could use the CDIAP (Common Denominator

Estimation Area) variable set forth in Table 10 or states as geographic domains.

v. Merge the multiple files into one consolidated file in a format compatible with the specialized 

software to be used.

vi. Sort the consolidated file by YEAR, STRATUMV, and YRSEQHH. 

vii. Run the specialized software on the consolidated file, computing estimates, variance estimates, 

and confidence intervals. For SUDAAN users, sampling levels or stages may be specified by the 

statement

NEST YEAR STRATUMV YRSEQHH / PSULEV = 3;

the specification of weights by 

WEIGHT NEWWT;

and the specification of estimation domains, for example, by the two statements

CLASS YEAR CDIAP STATE;

TABLES CDIAP; 

or 

CLASS YEAR CDIAP STATE;

TABLES STATE; 

8.3.2. Estimation of Multi-Year Contrasts 

Considerations similar to those for multi-year means arise in the estimation of contrasts between NISChild years. For example, a typical contrast of interest would be the difference between the immunization 

coverage parameters in 2020 and in 2021.

To make inferences concerning a multi-year contrast, the user will need to work with the original weights 

reported on the files and store them in a common variable. One must not divide the original weights by 

the number of years included in the contrast. For example, one may define the new, common weight 

variable as. 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 64

NEWWT2 = PROVWT_D/PROVWT_LL , if the child is in the 2011 PUF 

= PROVWT_D , if the child is in the 2012-2017 PUF

= PROVWT_C , if the child is in the 2018-2021 PUF.

The user should follow the seven-step procedure set forth in the section on multi-year means, using 

NEWWT2 in lieu of NEWWT. In SUDAAN, the user should also specify the contrast of interest 

through use of a CONTRAST statement or an appropriate regression model. For example, to compare the 

4:3:1:3:3:1 up-to-date estimate from 2020 to the 2021 estimate, SUDAAN users can use the following 

WEIGHT, VAR, and CONTRAST statements:

WEIGHT NEWWT2;

VAR PU431331;

CONTRAST YEAR = (-1 1);
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 65

Table 10: Cross-Walk between ITRUEIAP, ESTIAP, ESTIAP06-ESTIAP21, and Common Denominator Estimation Area (CDIAP), 

National Immunization Survey - Child, 2021 

CDIAP Area Name ITRUEIAP

(1995-2004) 

ESTIAP

(2005) 

ESTIAP06 

(2006) 

ESTIAP07 

(2007) 

ESTIAP08 

(2008) 

ESTIAP09 

(2009) 

ESTIAP10 

(2010) 

ESTIAP11 

(2011) 

ESTIAP12 

(2012) 

ESTIAP13 

(2013) 

ESTIAP14 

(2014) 

ESTIAP15 

(2015) 

Alabama 

20 AL-Jefferson County 21 21 20 20 20 20 20 20 20 20 20 20 

20 AL-Rest of State 20 20 20 20 20 20 20 20 20 20 20 20 

74 Alaska 74 74 74 74 74 74 74 74 74 74 74 74 

Arizona 

66 AZ-Maricopa County 67 67 67 66 66 66 66 66 66 66 66 66 

66 AZ-Rest of State 66 66 66 66 66 66 66 66 66 66 66 66 

46 Arkansas 46 46 46 46 46 46 46 46 46 46 46 46 

California 

68 CA-Fresno County 68 68 84 68 68 68 68 68 68 68 68 68 

68 CA-Los Angeles County 69 69 69 69 69 69 69 68 68 68 68 68 

68 CA-Northern CA 68 68 85 68 85 68 68 68 68 68 68 68 

68 CA-San Diego County 71 68 71 68 68 68 68 68 68 68 68 68 

68 CA-Santa Clara County 70 68 70 68 70 68 68 68 68 68 68 68 

68 CA-San Bernardino 

County 68 80 68 80 68 68 68 68 68 68 68 68 

68 CA-Alameda County 68 79 68 79 68 68 68 68 68 68 68 68 

68 CA-Rest of State 68 68 68 68 68 68 68 68 68 68 68 68 

Colorado 

60 CO-Denver 60 81 60 60 60 60 60 60 60 60 60 60 

60 CO-Rest of State 60 60 60 60 60 60 60 60 60 60 60 60 

1 Connecticut 1 1 1 1 1 1 1 1 1 1 1 1 

13 Delaware 13 13 13 13 13 13 13 13 13 13 13 13 

12 District of Columbia 12 12 12 12 12 12 12 12 12 12 12 12 

Florida 

22 FL-Miami-Dade County 24 22 24 24 24 22 22 22 22 22 22 22 

22 FL-Duval County 23 23 23 22 22 22 22 22 22 22 22 22 

22 FL-Orange County 22 22 22 22 91 22 22 22 22 22 22 22 

22 FL-Rest of State 22 22 22 22 22 22 22 22 22 22 22 22 

Georgia 

25 GA-Fulton/DeKalb 

Counties 26 26 26 25 25 25 25 25 25 25 25 25 

25 GA-Rest of State 25 25 25 25 25 25 25 25 25 25 25 25 

72 Hawaii 72 72 72 72 72 72 72 72 72 72 72 72 

75 Idaho 75 75 75 75 75 75 75 75 75 75 75 75 

Illinois 

35 IL-City of Chicago 35 35 35 35 35 35 35 35 35 35 35 35 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 66

CDIAP Area Name ITRUEIAP

(1995-2004) 

ESTIAP

(2005) 

ESTIAP06 

(2006) 

ESTIAP07 

(2007) 

ESTIAP08 

(2008) 

ESTIAP09 

(2009) 

ESTIAP10 

(2010) 

ESTIAP11 

(2011) 

ESTIAP12 

(2012) 

ESTIAP13 

(2013) 

ESTIAP14 

(2014) 

ESTIAP15 

(2015) 

34 IL-Madison and St. Clair 

Counties 34 34 34 34 92 34 34 34 34 34 34 34 

34 IL-Rest of State 34 34 34 34 34 34 34 34 34 34 34 34 

Indiana 

36 IN-Lake County 36 36 36 36 36 96 36 36 36 36 36 36 

36 IN-Marion County 37 36 37 37 36 37 36 36 36 36 36 36 

36 IN-Rest of State 36 36 36 36 36 36 36 36 36 36 36 36 

56 Iowa 56 56 56 56 56 56 56 56 56 56 56 56 

Kansas 

57 KS-Eastern KS 57 57 86 57 57 57 57 57 57 57 57 57 

57 KS-Rest of State 57 57 57 57 57 57 57 57 57 57 57 57 

27 Kentucky 27 27 27 27 27 27 27 27 27 27 27 27 

Louisiana 

47 LA-Orleans Parish 48 47 47 47 47 47 47 47 47 47 47 47 

47 LA-Rest of State 47 47 47 47 47 47 47 47 47 47 47 47 

4 Maine 4 4 4 4 4 4 4 4 4 4 4 4 

Maryland 

14 MD-City of Baltimore 15 15 15 14 15 15 14 14 14 14 14 14 

14 MD-Prince George’s 

County 14 14 14 14 14 14 14 103 14 14 14 14 

14 MD-Rest of State 14 14 14 14 14 14 14 14 14 14 14 14 

Massachusetts 

2 MA-City of Boston 3 2 3 2 2 2 2 2 2 2 2 2 

2 MA-Rest of State 2 2 2 2 2 2 2 2 2 2 2 2 

Michigan 

38 MI-City of Detroit 39 39 39 38 38 38 38 38 38 38 38 38 

38 MI-Rest of State 38 38 38 38 38 38 38 38 38 38 38 38 

Minnesota 

40 MN-Twin Cities 40 40 40 40 93 40 40 40 40 40 40 40 

40 MN-Rest of State 40 40 40 40 40 40 40 40 40 40 40 40 

28 Mississippi 28 28 28 28 28 28 28 28 28 28 28 28 

Missouri 

58 MO-St. Louis 

County/City 58 82 58 58 58 58 58 58 58 58 58 58 

58 MO-Rest of State 58 58 58 58 58 58 58 58 58 58 58 58 

61 Montana 61 61 61 61 61 61 61 61 61 61 61 61 

59 Nebraska 59 59 59 59 59 59 59 59 59 59 59 59 

Nevada 

73 NV-Clark County 73 83 73 73 73 73 73 73 73 73 73 73 

73 NV-Rest of State 73 73 73 73 73 73 73 73 73 73 73 73 

5 New Hampshire 5 5 5 5 5 5 5 5 5 5 5 5 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 67

CDIAP Area Name ITRUEIAP

(1995-2004) 

ESTIAP

(2005) 

ESTIAP06 

(2006) 

ESTIAP07 

(2007) 

ESTIAP08 

(2008) 

ESTIAP09 

(2009) 

ESTIAP10 

(2010) 

ESTIAP11 

(2011) 

ESTIAP12 

(2012) 

ESTIAP13 

(2013) 

ESTIAP14 

(2014) 

ESTIAP15 

(2015) 

New Jersey 

8 NJ-City of Newark 9 9 9 8 8 8 8 8 8 8 8 8 

8 NJ-Rest of State 8 8 8 8 8 8 8 8 8 8 8 8 

New Mexico 

49 NM-Southern NM 49 49 88 49 49 49 49 49 49 49 49 49 

49 NM-Rest of State 49 49 49 49 49 49 49 49 49 49 49 49 

New York 

11 NY-City of New York 11 11 11 11 11 11 11 11 11 11 11 11 

10 NY-Rest of State 10 10 10 10 10 10 10 10 10 10 10 10 

29 North Carolina 29 29 29 29 29 29 29 29 29 29 29 29 

62 North Dakota 62 62 62 62 62 62 62 62 62 62 62 62 

Ohio 

41 OH-Cuyahoga County 42 42 42 41 41 41 41 41 41 41 41 41 

41 OH-Franklin County 43 43 41 41 41 41 41 41 41 41 41 41 

41 OH-Rest of State 41 41 41 41 41 41 41 41 41 41 41 41 

50 Oklahoma 50 50 50 50 50 50 50 50 50 50 50 50 

76 Oregon 76 76 76 76 76 76 76 76 76 76 76 76 

Pennsylvania 

16 PA-Allegheny County 16 16 87 16 16 16 16 16 16 16 16 16 

17 PA-Philadelphia County 17 17 17 17 17 17 17 17 17 17 17 17 

16 PA-Rest of State 16 16 16 16 16 16 16 16 16 16 16 16 

6 Rhode Island 6 6 6 6 6 6 6 6 6 6 6 6 

30 South Carolina 30 30 30 30 30 30 30 30 30 30 30 30 

63 South Dakota 63 63 63 63 63 63 63 63 63 63 63 63 

Tennessee 

31 TN-Davidson County 33 33 31 31 31 31 31 31 31 31 31 31 

31 TN-Shelby County 32 32 32 31 31 31 31 31 31 31 31 31 

31 TN-Rest of State 31 31 31 31 31 31 31 31 31 31 31 31 

Texas 

55 TX-Bexar County 55 55 55 55 55 55 55 55 55 55 55 55 

54 TX-City of Houston 54 54 54 54 54 54 54 54 54 54 54 54 

51 TX-Dallas County 52 52 52 52 52 52 52 52 52 51 51 51 

51 TX-El Paso County 53 53 53 53 53 53 53 53 53 53 53 53 

51 TX-Hidalgo County 51 51 51 51 51 51 51 51 51 51 51 107 

51 TX-Travis County 51 51 51 51 51 51 51 51 51 51 51 51 

51 TX-Tarrant County 51 51 51 51 51 51 51 51 51 51 51 109 

51 TX-Rest of State 51 51 51 51 51 51 51 51 51 51 51 51 

64 Utah 64 64 64 64 64 64 64 64 64 64 64 64 

7 Vermont 7 7 7 7 7 7 7 7 7 7 7 7 

18 Virginia 18 18 18 18 18 18 18 18 18 18 18 18 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 68

CDIAP Area Name ITRUEIAP

(1995-2004) 

ESTIAP

(2005) 

ESTIAP06 

(2006) 

ESTIAP07 

(2007) 

ESTIAP08 

(2008) 

ESTIAP09 

(2009) 

ESTIAP10 

(2010) 

ESTIAP11 

(2011) 

ESTIAP12 

(2012) 

ESTIAP13 

(2013) 

ESTIAP14 

(2014) 

ESTIAP15 

(2015) 

Washington*

77 WA-Eastern WA 77 77 771 77 774 774 97 77 77 77 77 77 

77 WA-Western WA 77 77 77 773 774 774 102 77 77 77 77 77 

77 WA-King County 78 78 78 77 77 77 102 77 77 77 77 77 

77 WA-Rest of State 77 77 772 77 77 77 - 77 77 77 77 77 

19 West Virginia 19 19 19 19 19 19 19 19 19 19 19 19 

Wisconsin 

44 WI-Milwaukee County 45 45 45 44 44 44 44 44 44 44 44 44 

44 WI-Rest of State 44 44 44 44 44 44 44 44 44 44 44 44 

65 Wyoming 65 65 65 65 65 65 65 65 65 65 65 65 

- Puerto Rico - - - - - - - - - - 106 106 

* The estimation area WA-Eastern WA was introduced in 2006, and while this estimation area also existed in 2010, the county definition of the area changed, 

making cross-year comparisons inadvisable. The estimation area WA-Western WA, introduced in 2007, presents the same issue. The counties included in the 

area changed (e.g., in 2010 it included King County). Analysis of Washington state data across years should use the entire state as the “Common Denominator”.
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 69

Table 10 (continued): Cross-Walk between ITRUEIAP, ESTIAP, ESTIAP06-ESTIAP21, and 

Common Denominator Estimation Area (CDIAP), National Immunization 

Survey - Child, 2021 

CDIAP Area Name ESTIAP16 

(2016) 

ESTIAP17 

(2017) 

ESTIAP18 

(2018) 

ESTIAP19 

(2019) 

ESTIAP20 

(2020) 

ESTIAP21 

(2021) 

Alabama 

20 AL-Jefferson County 20 20 20 20 20 20 

20 AL-Rest of State 20 20 20 20 20 20 

74 Alaska 74 74 74 74 74 74 

Arizona 

66 AZ-Maricopa County 66 66 66 66 66 66 

66 AZ-Rest of State 66 66 66 66 66 66 

46 Arkansas 46 46 46 46 46 46 

California 

68 CA-Fresno County 68 68 68 68 68 68 

68 CA-Los Angeles County 68 68 68 68 68 68 

68 CA-Northern CA 68 68 68 68 68 68 

68 CA-San Diego County 68 68 68 68 68 68 

68 CA-Santa Clara County 68 68 68 68 68 68 

68 CA-San Bernardino 

County 68 68 68 68 68 68 

68 CA-Alameda County 68 68 68 68 68 68 

68 CA-Rest of State 68 68 68 68 68 68 

Colorado 

60 CO-Denver 60 60 60 60 60 60 

60 CO-Rest of State 60 60 60 60 60 60 

1 Connecticut 1 1 1 1 1 1 

13 Delaware 13 13 13 13 13 13 

12 District of Columbia 12 12 12 12 12 12 

Florida 

22 FL-Miami-Dade County 22 22 22 22 22 22 

22 FL-Duval County 22 22 22 22 22 22 

22 FL-Orange County 22 22 22 22 22 22 

22 FL-Rest of State 22 22 22 22 22 22 

Georgia 

25 GA-Fulton/DeKalb 

Counties 25 25 25 25 25 25 

25 GA-Rest of State 25 25 25 25 25 25 

72 Hawaii 72 72 72 72 72 72 

75 Idaho 75 75 75 75 75 75 

Illinois 

35 IL-City of Chicago 35 35 35 35 35 35 

34 IL-Madison and St. Clair 

Counties 34 34 34 34 34 34 

34 IL-Rest of State 34 34 34 34 34 34 

Indiana 

36 IN-Lake County 36 36 36 36 36 36 

36 IN-Marion County 36 36 36 36 36 36 

36 IN-Rest of State 36 36 36 36 36 36 

56 Iowa 56 56 56 56 56 56 

Kansas 

57 KS-Eastern KS 57 57 57 57 57 57 

57 KS-Rest of State 57 57 57 57 57 57 

27 Kentucky 27 27 27 27 27 27 

Louisiana 

47 LA-Orleans Parish 47 47 47 47 47 47 

47 LA-Rest of State 47 47 47 47 47 47 

4 Maine 4 4 4 4 4 4 

Maryland 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 70

CDIAP Area Name ESTIAP16 

(2016) 

ESTIAP17 

(2017) 

ESTIAP18 

(2018) 

ESTIAP19 

(2019) 

ESTIAP20 

(2020) 

ESTIAP21 

(2021) 

14 MD-City of Baltimore 14 14 14 14 14 14 

14 MD-Prince George’s 

County 14 14 14 14 14 14 

14 MD-Rest of State 14 14 14 14 14 14 

Massachusetts 

2 MA-City of Boston 2 2 2 2 2 2 

2 MA-Rest of State 2 2 2 2 2 2 

Michigan 

38 MI-City of Detroit 38 38 38 38 38 38 

38 MI-Rest of State 38 38 38 38 38 38 

Minnesota 

40 MN-Twin Cities 40 40 40 40 40 40 

40 MN-Rest of State 40 40 40 40 40 40 

28 Mississippi 28 28 28 28 28 28 

Missouri 

58 MO-St. Louis County/City 58 58 58 58 58 58 

58 MO-Rest of State 58 58 58 58 58 58 

61 Montana 61 61 61 61 61 61 

59 Nebraska 59 59 59 59 59 59 

Nevada 

73 NV-Clark County 73 73 73 73 73 73 

73 NV-Rest of State 73 73 73 73 73 73 

5 New Hampshire 5 5 5 5 5 5 

New Jersey 

8 NJ-City of Newark 8 8 8 8 8 8 

8 NJ-Rest of State 8 8 8 8 8 8 

New Mexico 

49 NM-Southern NM 49 49 49 49 49 49 

49 NM-Rest of State 49 49 49 49 49 49 

New York 

11 NY-City of New York 11 11 11 11 11 11 

10 NY-Rest of State 10 10 10 10 10 10 

29 North Carolina 29 29 29 29 29 29 

62 North Dakota 62 62 62 62 62 62 

Ohio 

41 OH-Cuyahoga County 41 41 41 41 41 41 

41 OH-Franklin County 41 41 41 41 41 41 

41 OH-Rest of State 41 41 41 41 41 41 

50 Oklahoma 50 50 50 50 50 50 

76 Oregon 76 76 76 76 76 76 

Pennsylvania 

16 PA-Allegheny County 16 16 16 16 16 16 

17 PA-Philadelphia County 17 17 17 17 17 17 

16 PA-Rest of State 16 16 16 16 16 16 

6 Rhode Island 6 6 6 6 6 6 

30 South Carolina 30 30 30 30 30 30 

63 South Dakota 63 63 63 63 63 63 

Tennessee 

31 TN-Davidson County 31 31 31 31 31 31 

31 TN-Shelby County 31 31 31 31 31 31 

31 TN-Rest of State 31 31 31 31 31 31 

Texas 

55 TX-Bexar County 55 55 55 55 55 55 

54 TX-City of Houston 54 54 54 54 54 54 

51 TX-Dallas County 52 52 51 52 51 51 

51 TX-El Paso County 53 53 51 53 51 51 

51 TX-Hidalgo County 51 51 107 51 51 51 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 71

CDIAP Area Name ESTIAP16 

(2016) 

ESTIAP17 

(2017) 

ESTIAP18 

(2018) 

ESTIAP19 

(2019) 

ESTIAP20 

(2020) 

ESTIAP21 

(2021) 

51 TX-Travis County 51 108 51 51 51 51 

51 TX-Tarrant County 51 51 109 51 51 51 

51 TX-Rest of State 51 51 51 51 51 51 

64 Utah 64 64 64 64 64 64 

7 Vermont 7 7 7 7 7 7 

18 Virginia 18 18 18 18 18 18 

Washington* 

77 WA-Eastern WA 77 77 77 77 77 77 

77 WA-Western WA 77 77 77 77 77 77 

77 WA-King County 77 77 77 77 77 77 

77 WA-Rest of State 77 77 77 77 77 77 

19 West Virginia 19 19 19 19 19 19 

Wisconsin 

44 WI-Milwaukee County 44 44 44 44 44 44 

44 WI-Rest of State 44 44 44 44 44 44 

65 Wyoming 65 65 65 65 65 65 

- Puerto Rico 106 - - 106 106 106 

* The estimation area WA-Eastern WA was introduced in 2006, and while this estimation area also existed in 2010, 

the county definition of the area changed, making cross-year comparisons inadvisable. The estimation area WAWestern WA, introduced in 2007, presents the same issue. The counties included in the area changed (e.g., in 2010 it 

included King County). Analysis of Washington state data across years should use the entire state as the “Common 

Denominator”.
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 72

9. Summary Tables 

Appendix F contains seven tables. Appendix Table F.1 lists the 59 estimation areas for the 2021 NISChild by state. At the national level and for each state and estimation area, it provides the estimated 

population total of children aged 19 through 35 months of age in 2021, and (from 2021 NIS-Child data 

collection) the number of children with completed household interviews and number of children with 

adequate provider data.

Appendix Tables F.2 through F.6 summarize pairs of variables: age group of child by maternal education 

(Appendix Table F.2), age group by family poverty status (Appendix Table F.3), race/ethnicity by family 

poverty status (Appendix Table F.4), age group by race/ethnicity (Appendix Table F.5), and age group by 

sex (Appendix Table F.6). Each of these tables gives the unweighted and weighted counts of children who 

have completed household interviews and the unweighted and weighted counts of children with adequate 

provider data.

Appendix Table F.7 presents estimates of vaccination coverage and symmetric 95% confidence intervals 

obtained from SUDAAN. The data user should obtain the same estimates from the 2021 NIS-Child

public-use data file. (As noted in Section 1 of this report, these estimates will differ from those appearing 

on ChildVaxView and in the MMWR, which use multiple years of NIS-Child data and apply to the 

population of children born in particular years rather than using a single year of NIS-Child data and 

applying to the population of children age 19-35 months.) 

Appendix G contains four tables and time-series charts. Table G.1 and Figure G.1 show key components 

of the NIS-Child response rates and the CASRO response rates for the landline sample by year of the 

survey. Table G.2 and Figure G.2 show key components of the NIS-Child response rates and the CASRO 

response rates for the cellular phone sample by year of the survey. Table G.3 and Figure G.3 show the 

CASRO response rates for the combined landline and cellular phone samples. Table G.4 and Figure G.4 

show vaccination coverage estimates since 1995.
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 73

Appendix H shows the vaccine type codes used in the 2021 NIS-Child public-use data file. 

Appendix I presents key response rate components and the overall CASRO response rate by estimation 

area in the 2021 NIS-Child. 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 74

10. Assessment of Total Survey Error 

Assessing the validity of the NIS-Child estimates of vaccination coverage is a critical and ongoing aspect 

of the NIS-Child surveillance program. CDC frequently conducts evaluation studies and controlled 

experiments to understand the causes and impacts of sampling and nonsampling errors on the estimates 

and to enable formulation of methodological refinements that have the demonstrated capacity to improve 

data quality. As landline phone use decreased and cellular phone use increased dramatically over the past 

decade, and the NIS-Child transitioned first from a single-frame landline RDD sampling design to a dualframe landline and cellular phone RDD design and then to a single-frame cellular phone RDD design, 

CDC has monitored the NIS-Child estimates utilizing a Total Survey Error (TSE) approach.

TSE is the sum of the errors that arise at every step of a survey, including both sampling error and 

nonsampling errors such as coverage, nonresponse, and measurement errors (Mulry and Spencer, 1991). 

Pooling information from multiple evaluations of their precision and accuracy, we have conducted TSE

analyses for the 2009-2013 NIS-Child and NIS-Teen data (Molinari et al. 2011; NORC 2011; Pineau et 

al. 2012; Pineau et al. 2013; Skalland et al. 2016; Wolter et al. 2017b) and for the 2018-2020 NIS-Child 

and NIS-Teen data (see the Data User’s Guides for the 2018-2020 NIS-Child and NIS-Teen public use 

data files). 

An assessment based on 2021 NIS-Child data was conducted in 2022, with results summarized 

below. 

Comparison of Demographic Distributions. Demographic distributions (age, sex, mother’s 

race/ethnicity, mother’s education, mother’s age) among children with adequate provider data

were compared to benchmark values derived from natality data supplied by the National Vital 

Statistics System. When using design weights that have not been adjusted for nonresponse or 

calibrated to external population totals, demographic distributions as estimated in the NIS-Child

were generally close to the benchmark distributions. Before calibration of the weights to external 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 75

population totals, the 2021 NIS-Child somewhat over-represented children whose mothers are 

college graduates, non-Hispanic White, or age 30 or greater, as well as children 30 to 35 months old. 

The survey somewhat under-represented children whose mothers are not college graduates, are 

Hispanic or non-Hispanic Black, or are age 20 to 29 years, as well as children 24 to 29 months old. 

When using the final weights that have been adjusted for nonresponse and calibrated to external 

population totals, the demographic differences between survey and population are reduced, but the 

2021 NIS-Child still overrepresented children whose mothers are four-year college graduates

(40.0% in survey, 33.2% in population) or are age 30 or greater (68.3% in survey, 58.2% in 

population). 

Comparison to IISAR Vaccination Coverage Rates. NIS-Child vaccination coverage rate estimates 

were compared to vaccination coverage rates reported in the Immunization Information Systems 

Annual Report (IISAR). Sponsored and conducted by NCIRD, the IISAR is an annual assessment 

of Immunization Information Systems (IIS)2 activity among the 64 immunization program 

awardees, which include the 50 states, 6 cities (Chicago, District of Columbia, Houston, New York 

City, Philadelphia, and San Antonio), and 8 U.S. territories. To evaluate each awardee’s 

performance, the immunization program manager in the awardee area is asked to complete a selfadministered, web-based questionnaire asking for demographic and immunization information, 

public and private provider site participation levels, and information about achievement of IIS 

functional standards. NCIRD provides competitive supplemental funds to awardees that have met 

high data timeliness and participation (child and adolescent) in the IIS. During the period 2013-

2017 six awardees were recognized as IIS sentinel sites, including Michigan, Minnesota, North 

Dakota, New York City, Oregon, and Wisconsin. Because of increased timeliness and higher child 

and adolescent saturation levels in the IIS, vaccination coverage rates reported in IISAR by sentinel 

2 State IISs are computer databases that aspire to contain information about all of the doses of all vaccines 

administered to all children resident within the state. State IISs vary in their completeness of both children and the 

doses they received.
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 76

sites are thought to be relatively more accurate than vaccination rates reported by non-sentinel 

sites. 

NIS-Child vaccination coverage rate estimates for 2020 were compared to 2020 IISAR vaccination 

coverage rates. Because 2021 IISAR vaccination coverage rates were not available at the time of the 

assessment, the 2020 comparison served as the most current information available about the 

relative accuracy of the 2021 NIS-Child. NIS-Child vaccination coverage rate estimates were found 

to be generally higher than IISAR vaccination coverage rates. For the six sentinel sites, reasonably 

good agreement was observed between the NIS-Child and IISAR vaccination coverage rates, with 

the absolute difference in rates in 2020 falling within 5 percentage points for the combined 7-

vaccine series for Minnesota, Michigan, and Wisconsin; for North Dakota and Oregon, the absolute 

differences were larger, but still within 10 percentage points; for New York City, the difference was 

slightly greater than 10 percentage points. Further, the child participation rate – the proportion of 

children in the IIS jurisdiction with two or more vaccine doses in the IIS database3

 – was 

determined to be a reasonable indicator of the quality of the corresponding IIS database, because

the IIS vaccination coverage rate was found to increase as the child participation rate increased. It 

was also observed (Figure 1) that the difference between NIS-Child and IISAR vaccination 

coverage rates for the combined 7-vaccine series declines as the child participation rate increases 

(i.e., as the quality of the IIS increases). These findings are consistent with the view that IIS 

vaccination coverage rates converge towards NIS-Child vaccination coverage rates as the quality of 

the IIS increases.

3 When setting the denominator for the participation rate calculation, some IIS use an external estimate of the 

number of children living in the jurisdiction rather than a count of children in the IIS itself; this results in some IIS 

reporting a participation rate of over 100 percent.
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 77

Figure 1: Scatter Plot of Percentage Point Difference between NIS-Child and IISAR Vaccination 

Coverage Rates for the Combined 7-Vaccine Series vs. IIS Child Participation Rate 

(CPR) with Regression Line: 56 Estimation Areas

Comparison of Health Insurance Distributions. NIS-Child health insurance distributions were 

compared to similar distributions produced by the Current Population Survey Annual Social and 

Economic Supplements (CPS ASEC), the National Health Interview Survey (NHIS), and the 

American Community Survey (ACS). All of these surveys use somewhat different definitions of 

insurance status and report for different age ranges of children. Nevertheless, we found the NISChild distributions to be broadly similar to those from the CPS, NHIS, and ACS, but with some 

differences. NIS-Child estimates of percent of children with any public insurance (52.8% in 2020; 

57.5% in 2021) were higher than the corresponding benchmark estimates (44.7% (NHIS), 38.8% 

(CPS ASEC), and 43.8% (ACS) in 2020; 42.1% (CPS ASEC) in 2021), and the NIS-Child estimates 

of uninsured children (2.9% in 2020; 1.9% in 2021) were lower than the estimates from the 

benchmark surveys (3.0% (NHIS), 5.6% (CPS ASEC), and 4.3% (ACS) in 2020; 5.0% (CPS ASEC) 

in 2021). 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 78

Comparison to State Immunization Surveys. A comparison was undertaken of NIS-Child vaccination 

coverage rate estimates to estimates from eight state immunization surveys: Florida (Blackmore, 

2022), Georgia (Machado et al., n.d.), Kansas (Gillespie, 2019), Michigan (Michigan Department of 

Health and Human Services, 2022), Tennessee (Tennessee Department of Health, 2022), Virginia 

(Virginia Department of Health, n.d.), Washington (Washington State Department of Health, n.d.), 

and Wisconsin (Wisconsin Department of Health Services, n.d.). Some aspects of NIS-Child and 

state survey practices are not comparable and limit the importance of the results. That said, there is 

reasonable agreement between NIS-Child and state vaccination rates in many of the states. Where 

NIS-Child and state practices were comparable, similar vaccination rates were found. For state 

surveys that rely on IIS vaccination histories, NIS-Child rates were generally found to be higher 

than the corresponding states’ rates. While this work did not provide specific measures of error in 

NIS-Child statistics, it did provide general support for the accuracy of the vaccination coverage 

rates.

Next, an assessment of all sources of error in the 2021 NIS-Child was conducted, including sampleframe coverage error, nonresponse error, and measurement error; the component errors were then

combined to assess total survey error. The change in total survey error between the 2020 NIS-Child 

and 2021 NIS-Child was also estimated.

Coverage Error. The NIS-Child cellular phone RDD sampling frame fails to cover the landline only 

and phoneless populations; vaccination coverage rates in the former were estimated using data 

collected in the 2017 NIS-Child (the last year a dual-frame landline and cellular phone sample was 

fielded for the NIS) and vaccination coverage rates in the latter were estimated using data collected 

in the 2012 NHIS Provider Record Check. The vaccination coverage rates in the population covered 

by the sampling-frame were found to be higher than the vaccination rates in the uncovered 

population. Because the sampling-frame uncovered population is so small relative to the covered 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 79

population, however, mean sampling-frame coverage error was estimated to be very minor, at 0.1 

percentage points or less for all vaccines/series examined. 

Nonresponse Error. Nonresponse error in the 2021 NIS-Child was assessed through comparison to 

the cellular phone domain within the combined 2019 and 2021 NHIS. (2019 NHIS data were used in 

place of 2020 data because the 2020 NHIS shifted data collection for four months from in-person to 

all-telephone interviewing due to the COVID-19 pandemic, which resulted in lower response rates.) 

NHIS does not offer direct estimates of vaccination coverage rates. Instead, a model-based 

technique was used to impute NHIS vaccination status, and then the resulting NHIS vaccination 

coverage rates (treated as vaccination coverage rates void of nonresponse error) were compared to 

NIS-Child vaccination coverage rates, with the difference treated as nonresponse error in the NISChild. Despite nonresponse in the 2021 NIS-Child, including household nonresponse, non-consent 

to contact vaccination providers, and provider nonresponse, mean nonresponse error in vaccination 

rates was estimated to be modest at most (0.7 to 2.1 percentage points in absolute value across the 

four vaccines/series examined when using design weights, and 0.7 to 1.4 percentage points in 

absolute value when using final weights that account for the survey’s nonresponse adjustments). Of 

the vaccines/series examined, none of the nonresponse errors were found to be significantly 

different from zero. 

Measurement Error. A form of measurement error called “provider under-reporting” error was 

assessed. Sometimes called “under-ascertainment,” provider under-reporting error arises when a 

child with adequate provider data is truly vaccinated but is reported as unvaccinated for one or 

more recommended doses in the child’s provider-reported vaccination history. Under-reporting 

error can occur if the household respondent fails to nominate all of the child’s vaccination 

providers, if one or more of the child’s nominated vaccination providers fails to report a 

vaccination history for the child, or if one or more of the child’s nominated providers reports a 

vaccination history but fails to report all of the vaccinations the child has received. Underreporting 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 80

error was estimated using data from projects sponsored by CDC in which the 2017 NIS-Child 

sample of children in 20 jurisdictions and the 2019 NIS-Child sample of children in 5 jurisdictions

was matched to the state or local IIS for the jurisdiction. In this work, the standard of truth for a 

given child is taken to be the synthesis of the NIS-Child and IIS vaccination histories. In prior 

studies conducted in 2012 and 2013 using similar methods, measurement error was found to be by 

far the largest component of error in the NIS-Child vaccination rates. Similar conclusions were 

reached for the 2021 NIS-Child, where it was estimated that measurement error depressed 

observed vaccination rates by about 2 to 8 percentage points.

Total Survey Error. Finally, all of the component errors were combined to assess the distribution of 

total error in the NIS-Child vaccination coverage rates, using a Monte Carlo technique. The mean 

of the distribution is an estimate of the total survey error, and the 2.5 and 97.5 percentiles of the 

distribution form a 95% credible interval for the total error. The estimated component errors and 

total survey errors are presented in Table 11. For the 4+ DTaP vaccination coverage rate, the mean 

of the TSE distribution was found to be -3.1 percentage points with a 95% credible interval of (-6.5, 

0.9) percentage points. That is, the NIS-Child vaccination coverage rate was on average about 3.1 

percentage points too low. For the 1+ MMR vaccination coverage rate, the mean of the TSE 

distribution was found to be -3.1 percentage points with a 95% credible interval of (-5.1, -0.2) 

percentage points; for the Hepatitis B birth dose rate, the mean of the TSE distribution was 

estimated at -4.4 percentage points with a 95% credible interval of (-7.4, -1.0) percentage points; 

and the mean of the TSE distribution for the combined 7-vaccine series was estimated to be -8.7

percentage points with a 95% credible interval of (-12.3, -4.7) percentage points. These results 

suggest that, according to best estimates, the 2021 NIS-Child underestimated vaccination coverage 

rates. As in prior NIS-Child total survey error assessments, under-ascertainment of the providerreported vaccination history was found to be the main source of total survey error.
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 81

Table 11: Mean and 95% Credible Interval for the Estimated Total Survey Error (TSE) 

Distribution and Component Error Distributions for National Vaccination Coverage 

Rate Estimates, National Immunization Survey - Child, 2021

Vaccine or 

Series Component Mean TSE(pct points)

95% Credible Interval

(pct points)

4+ DTaP

TSE (final weighted) -3.1 (-6.5, 0.9)

TSE (design weighted) -2.4 (-5.7, 1.7)

Noncoverage error 0.1 (-0.1, 0.4)

Nonresponse error 2.2 (-1.5, 6.6)

Measurement error -4.7 (-6.1, -3.1)*

Sampling error 0.1 (-1.5, 1.8)

1+ MMR

TSE (final weighted) -3.1 (-5.1, -0.2)*

TSE (design weighted) -3.1 (-5.1, -0.2)*

Noncoverage error 0.1 (0.0, 0.3)

Nonresponse error -0.6 (-3.0, 2.6)

Measurement error -2.6 (-3.6, -1.4)*

Sampling error 0.0 (-1.1, 1.4)

HepB Birth 

Dose 

TSE (final weighted) -4.4 (-7.4, -1.0)*

TSE (design weighted) -4.6 (-7.5, -1.1)*

Noncoverage error 0.1 (0.0, 0.3)

Nonresponse error -1.2 (-4.5, 2.4)

Measurement error -3.4 (-4.8, -2.0)*

Sampling error 0.0 (-1.4, 1.6)

Combined 7-

vaccine series

TSE (final weighted) -8.7 (-12.3, -4.7)*

TSE (design weighted) -7.1 (-10.6, -3.1)*

Noncoverage error 0.1 (-0.1, 0.4)

Nonresponse error 1.0 (-3.0, 5.4)

Measurement error -8.2 (-10.0, -6.3)*

Sampling error 0.0 (-2.0, 2.1)

* 95% credible interval excludes zero.

Change in Total Survey Error. Change in TSE between the 2020 and 2021 NIS-Child was measured 

using the bridging cohort method introduced by NCIRD (Yankey, Hill, Elam-Evans, et al. 2015). 

Each survey quarter includes children born in 20 monthly birth cohorts. Every pair of adjacent 

survey quarters spans 23 monthly birth cohorts, of which 17 are in common and 6 are not in 

common. In turn, every survey year represents 29 monthly birth cohorts. Every pair of adjacent 

survey years spans 39 monthly birth cohorts, of which 17 are in common and 22 are not in 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 82

common. The 17 common months comprise the bridging cohort, and for 2020 and 2021, the 

bridging cohort extends from children born in January 2018 through children born in May 2019. 

Consider a vaccination coverage rate estimated from the bridging cohort as of a given child age, 

such as 19 months or 24 months. Two estimates are possible, one using the sample of children in the 

bridging cohort within the 2020 NIS-Child sample and the second using the corresponding sample 

of children within the 2021 NIS-Child sample. Ideally, the two estimators should exhibit the same 

statistical expectation (i.e., average value in hypothetical repeated sampling). A large difference 

between the two estimates may signal a change in the statistical expectation of total survey error

from one survey year to the next, which could result from a change in the distribution of samplingframe coverage error, nonresponse error, or measurement error. Differences may also result 

simply from the effects of random sampling error.

Table 12 presents the two estimates of vaccination coverage for children as of 19 months of age for 

the 2020-2021 bridging cohort. None of the differences between the 2020 and 2021 national-level 

vaccination coverage rates for the bridging cohort were found to be statistically significant at the 

0.05 level. That is, no evidence was found of a change in the statistical expectation of total survey 

error between the 2020 NIS-Child and the 2021 NIS-Child.
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 83

Table 12: Difference Between the Estimates* for the Bridging Birth Cohort† by Age 19 Months, 

National Immunization Survey - Child, 2020 vs. 2021

Description

2020 2021 Difference

Est Std Error Est Std Error Est Std Error pp-value for Test 

of No Difference

3+ DTaP/DTP/DT by 19 months 93.8 0.43 93.7 0.52 -0.2 0.67 0.818

4+ DTaP/DTP/DT by 19 months 71.7 0.84 71.5 0.90 -0.2 1.23 0.889

3+ Polio by 19 months 92.9 0.45 92.4 0.57 -0.5 0.73 0.509

1+ MMR by 19 months 90.3 0.54 89.4 0.59 -0.9 0.80 0.282

3+ Hib by 19 months 90.6 0.52 90.5 0.60 0.0 0.79 0.956

Hib partial series by 19 months 93.3 0.46 92.9 0.53 -0.3 0.70 0.664

Hib full series by 19 months 75.0 0.82 73.5 0.87 -1.5 1.19 0.199

1+ Varicella by 19 months, 

excluding shots before 12 months 89.2 0.56 87.6 0.68 -1.6 0.88 0.069

3+ Hepatitis B by 19 months 91.4 0.53 91.7 0.59 0.3 0.80 0.734

3+ Pneumococcal by 19 months 93.0 0.44 92.8 0.53 -0.2 0.69 0.775

4+ Pneumococcal by 19 months 79.6 0.74 79.3 0.81 -0.3 1.09 0.778

1+ Hepatitis A by 19 months 84.2 0.68 83.0 0.77 -1.2 1.02 0.261

2+ Hepatitis A by 19 months 26.2 0.79 28.3 0.88 2.1 1.18 0.083

2+ or 3+ Rotavirus depending on 

type by 19 months 78.8 0.77 79.2 0.81 0.4 1.12 0.722

7-series by 19 months 62.6 0.90 60.1 0.97 -2.4 1.32 0.065

1+ Hepatitis B-containing on day 

of birth or on day 1, 2 or 3 

following birth

79.5 0.79 79.2 0.83 -0.4 1.15 0.754

Unvaccinated children 0.74 0.12 0.77 0.14 0.0 0.18 0.872

2+ Flu by 19 months, doses at least 

24 days apart 60.7 0.91 62.1 0.93 1.4 1.30 0.280

* National-level estimates computed among children with adequate provider data, excluding children from U.S. territories.

† The bridging birth cohort used for this analysis of the 2020 and 2021 NIS-Child includes children born between January 2018 

and May 2019.
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 84

11. Limitations 

The findings in this report are subject to at least four limitations. First, because NIS-Child is a telephone 

survey, results are weighted to be representative of all children aged 19 through 35 months. Although 

statistical adjustments were made to account for non-response and households without cellular phones, 

some bias might remain. Second, underestimates of vaccination coverage might have resulted from the 

exclusive use of provider-reported vaccination histories because completeness of these records is 

unknown. Third, although national estimates of vaccination coverage are precise, estimates for state and 

local areas should be interpreted with caution because their sample sizes are smaller and their confidence 

intervals generally are wider than those for national estimates. Finally, analysis of trends across data years 

that span from 2010 and earlier to 2011-2017 and from 2011-2017 to 2018-2021 are subject to potential 

bias that may remain after weighting adjustments because of the switch from landline to dual landline and 

cellular phone frames in 2011, and from dual landline and cellular phone frames to a single cellular phone 

frame in 2018 (Hill et al., 2019). In addition, analysis of trends across data years that span from 2011 to 

2017 are subject to potential bias that may remain after weighting adjustments because of the expansions 

and reductions of the share of the total sample that came from the cellular phone frame across these years. 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 85

12. Citations for NIS-Child Data 

In publications, please acknowledge the original data source. The citation for the 2021 NIS-Child publicuse data file is:

U.S. Department of Health and Human Services (DHHS). National Center for Immunization and 

Respiratory Diseases . The 2021 National Immunization Survey-Child, Atlanta, GA : Centers for Disease 

Control and Prevention, 2022. 

Information about the NIS-Child is located at http://www.cdc.gov/vaccines/imz-managers/nis/about.html. 

The NIS-Child public-use data files are located at http://www.cdc.gov/vaccines/imzmanagers/nis/datasets.html. 

Please place the acronym “NIS-Child” in the titles, keywords, or abstracts of journal articles and other 

publications in order to facilitate retrieval of such materials in bibliographic searches. 

The following publications use NIS-Child data, published from 2010 or later: 

2021 

Choudhury AR, Polachek SW. The impact of paid family leave on the timely vaccination of infants. 

Vaccine 2021;39: 2886–2893. 

Doll MK, Weitzen SD, Morrison KT. Trends in the uptake of pediatric measles-containing vaccine in the 

United States: A Disneyland effect? Vaccine 2021;39(2):357-363. 

Fu LY, Torres R, Caleb S, Cheng YI, Gennaro E, Thoburn E, McLaughlin J, Alexander-Parrish R, Wang 

J. Vaccination coverage among young homeless children compared to US national immunization survey 

data. Vaccine 2021;Oct 29;39(45):6637-6643. doi: 10.1016/j.vaccine.2021.09.073. 

Hill HA, Yankey D, Elam-Evans LD, Singleton JA, Sterrett N. Vaccination coverage by age 24 months 

among children born in 2017 and 2018 – National Immunization Survey-Child, United States, 2018-2020. 

MMWR Morb Mortal Wkly Rep 2021 Oct 15;70(41):1435-1440. doi 10.15585/mmwr/mm7041a1. 

Kulkarni AA, Desai RP, Alcala ́HE, Balkrishnan R. Persistent disparities in immunization rates for the 

seven-vaccine series among infants 19–35 months in the United States, Health Equity 2021:5:1, 135–139, 

DOI: http://dx.doi.org/10.1089/heq.2020.0127

2020 

Adebanjo TA, Pondo T, Yankey D, Hill HA, Gierke R, Apostol M, Barnes M, Petit S, Farley M, Harrison 

LH, Holtzman C, Baumbach J, Bennett N, McGuire S, Thomas A, Schaffner W, Beall B,

Whitney CG, Pilishvili T. Pneumococcal conjugate vaccine breakthrough infections: 2001-2016. 

Pediatrics 2020 Mar;145(3):e20190836.

Bleser WK, Salmon DA, Miranda PY. A hidden vulnerable population: Young children up-to-date on 

vaccine series recommendations except influenza vaccines. PLoS One 2020;15(6):e0234466. 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 86

Hill HA, Yankey D, Elam-Evans LD, Singleton JA, Pingali SC, Santibanez TA. Vaccination Coverage by 

Age 24 Months Among Children Born in 2016 and 2017 — National Immunization Survey-Child, United 

States, 2017–2019. MMWR Morb Mortal Wkly Rep 2020;69:1505–1511. 

DOI: http://dx.doi.org/10.15585/mmwr.mm6942a1

Vader DT, Lee BK, Evans AA. Hepatitis B birth dose effects on childhood immunization in the U.S. 

American Journal of Preventive Medicine 2020;58(2):208-215. 

2019 

Beauregard JL, Hamner HC, Chen J, Avila-Rodriguez W, Elam-Evans LD, Perrine CG. Racial Disparities 

in Breastfeeding Initiation and Duration Among U.S. Infants Born in 2015. MMWR Morb Mortal Wkly 

Rep 2019;68:745–748. DOI: http://dx.doi.org/10.15585/mmwr.mm6834a3

Grubesic TH, Durbin KM. A spatial analysis of breastfeeding and breastfeeding support in the United 

States: The leaders and laggards landscape. Journal of Human Lactation 2019. Epub ahead of print. 

Hamad R, Modrek S, White JS. Paid family leave effects on breastfeeding: A quasi-experimental study of 

US policies. Am J Public Health 2019;109:164-166. 

Hill HA, Singleton JA, Yankey D, Elam-Evans LD, Pingali SC, Kang Y. Vaccination Coverage by Age 

24 Months Among Children Born in 2015 and 2016 — National Immunization Survey-Child, United 

States, 2016–2018. MMWR Morb Mortal Wkly Rep 2019;68:913–918. DOI: 

http://dx.doi.org/10.15585/mmwr.mm6841e2external icon 

Li R, Perrine CG, Anstey EH, Chen J, MacGowen CA, Elam-Evans LD. Breastfeeding trends by 

race/ethnicity among US children born from 2009 to 2015. JAMA Pediatr 2019 Oct 14;173(12):e193319.

Sederdahl BK, Orenstein WA, Yi J, Anderson EJ, Bednarczyk RA. Missed opportunities for rotavirus 

vaccination. Pediatrics 2019;143(5) (online) 

Wolter KM, Ganesh N, Copeland KR, Singleton JA, Khare M. Estimation tools for reducing the impact 

of sampling and nonresponse errors in dual-frame RDD telephone surveys. Stat Med 2019 38(23):4718-

4732. 

2018 

Hill HA, Elam-Evans LD, Yankey D, Singleton JA, Kang Y. Vaccination Coverage Among Children 

Aged 19–35 Months — United States, 2017. MMWR Morb Mortal Wkly Rep 2018;67(40):1123-1128. 

DOI: http://doi.org/10.15585/mmwr.mm6740a4

Lavrakas PJ, Skalland B, Ward C, Geng C, Welch V, Jeyarajah J, Knighton C. Testing the effects of 

envelope features on survey response in a telephone survey advance letter mailing experiment. Journal of 

Survey Statistics and Methodology 2018;6:262-283. 

Mulligan K, Snider JT, Arthur P, Frank G, Tebeka M, Walker A, Abrevaya J. Examination of universal 

purchase programs as a driver of vaccine uptake among US States, 1995-2014. Vaccine 2018;36:4032-

4038. 

Zhao Z, Smith PJ, Hill HA. Factors associated with missed opportunities for simultaneous administration 

of the fourth dose of pneumococcal conjugate vaccine for children in the United States. International 

Journal of Science and Research Methodology 2018;9(1):149-162. 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Page 87

2017 

Anstey EH, Chen J, Elam-Evans LD, Perrine CG. Racial and Geographic Differences in Breastfeeding — 

United States, 2011–2015. MMWR Morb Mortal Wkly Rep 2017;66:723–727. 

Casillas SM, Bednarczyk RA. Missed opportunities for hepatitis A vaccination, National Immunization 

Survey-Child, 2013. J Pediatr 2017;187:265-71. 

Chen W, Elam-Evans LD, Hill HA, Yankey D. Employment and socioeconomic factors associated with 

children’s up-to-date vaccination status. Clinical Pediatrics 2017;56(4):348-356. 

Childs L, Bednarczyk RA. Estimating pertussis susceptibility among 0—23-month-old children in the 

United States. Pediatr Infect Dis J 2017;36:705-711. 

Hill HA, Elam-Evans LD, Yankey D, Singleton JA, Kang Y. Vaccination coverage among children aged 

19-35 months – United States, 2016. MMWR Morb Mortal Wkly Rep 2017;66:1171-1177. 

Kurosky SK, Davis KL, Galindo CM. Effect of combination vaccines on hepatitis B vaccine compliance 

in children in the United States. Pediatr Infect Dis J 2017;36:e179-e196. 

Kurosky SK, Davis KL, Krishnarajah G. Effect of combination vaccines on completion and compliance 

of childhood vaccinations in the United States. Human Vaccines & Immunotherapeutics 

2017;13(11):2494-2502. 

Lo NC, Hotez PJ. Public health and economic consequences of vaccine hesitancy for measles in the 

United States. JAMA Pediatrics 2017;17(9):887-892. 

Varan AK, Rodriguez-Lainz A, Hill HA, Elam-Evans LD, Yankey D, Li Q. Vaccination coverage 

disparities between foreign-born and U.S.-born children aged 19-35 months, United States, 2010-2012. J 

Immigrant Minority Health 2017;19:779-789. 

Zhao Z, Smith PJ, Hill HA. Missed opportunities for simultaneous administration of the fourth dose of 

DTaP among children in the United States. Vaccine 2017;35:3191-3195. 

2016 

Cardemil CV, Cullen KA, Harris L, Greby SM, Santibanez TA. Factors associated with provider 

reporting of child and adolescent vaccination history to Immunization Information Systems: Results from 

the National Immunization Survey, 2006-2012. J Public Health Management Practice 2016;22(3):245-

254. 

Curran D, Terlinden A, Poirrier J-E, Masseria C, Krishnarajah G. Vaccine timeliness: A cost analysis of 

the potential implications of delayed pertussis vaccination in the US. Pediatr Infect Dis J 2016;35(5):542-

547. 

Gilkey MB, McRee A-L, Magnus BE, Reiter PL, Dempsey AF, Brewer NT. Vaccination confidence and 

parental refusal/delay of early childhood vaccines. PLOS ONE | DOI: 10.1371/journal/pone.0159087 July 

8, 2016. 

Hill HA, Elam-Evans LD, Yankey D, Singleton JA, Dietz V. Vaccination Coverage Among Children 

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Page 97

Appendix A: Glossary of Abbreviations and Terms 

3:3:1 The series of 3 or more DTaP vaccinations, 3 or more polio vaccinations, and 1 or 

more MCV vaccinations

4:3:1 The series of 4 or more DTaP vaccinations, 3 or more polio vaccinations, and 1 or 

more MCV vaccinations

4:3:1:3 The series of 4 or more DTaP vaccinations, 3 or more polio vaccinations, 1 or more 

MCV vaccinations, and 3 or more Hib vaccinations of any type

4:3:1:3* The series of 4 or more DTaP vaccinations, 3 or more polio vaccinations, 1

(routine Hib) or more MCV vaccinations, and 3 or 4 Hib vaccinations depending on manufacturer 

(routine recommendation) 

4:3:1:3:3 The series of 4 or more DTaP vaccinations, 3 or more polio vaccinations, 1 or more 

MCV vaccinations, 3 or more Hib vaccinations of any type, and 3 or more hepatitis B 

vaccinations

4:3:1:3*:3 The series of 4 or more DTaP vaccinations, 3 or more polio vaccinations, 1

(routine Hib) or more MCV vaccinations, 3 or 4 Hib vaccinations depending on manufacturer 

(routine recommendation), and 3 or more hepatitis B vaccinations

4:3:1:3:3:1 The series of 4 or more DTaP vaccinations, 3 or more polio vaccinations, 1 or more 

MCV vaccinations, 3 or more Hib vaccinations of any type, 3 or more hepatitis B 

vaccinations, and 1 or more varicella vaccinations given at age 12 months or older

4:3:1:3*:3:1 The series of 4 or more DTaP vaccinations, 3 or more polio vaccinations, 1 or

(routine Hib) more MCV vaccinations, 3 or 4 Hib vaccinations depending on manufacturer (routine 

recommendation), 3 or more hepatitis B vaccinations, and 1 or more varicella 

vaccinations given at age 12 months or older

4:3:1:3:3:1:3 The series of 4 or more DTaP vaccinations, 3 or more polio vaccinations, 1 or more 

MCV vaccinations, 3 or more Hib vaccinations of any type, 3 or more hepatitis B 

vaccinations, 1 or more varicella vaccinations given at age 12 months or older, and 3 

or more pneumococcal vaccinations

4:3:1:3*:3:1:3 The series of 4 or more DTaP vaccinations, 3 or more polio vaccinations, 1 or

(routine Hib) more MCV vaccinations, 3 or 4 Hib vaccinations depending on manufacturer (routine 

recommendation), 3 or more hepatitis B vaccinations, 1 or more varicella 

vaccinations given at age 12 months or older, and 3 or more pneumococcal 

vaccinations

4:3:1:3:3:1:4 The series of 4 or more DTaP vaccinations, 3 or more polio vaccinations, 1 or more 

MCV vaccinations, 3 or more Hib vaccinations of any type, 3 or more hepatitis B 

vaccinations, 1 or more varicella vaccinations given at age 12 months or older, and 4 

or more pneumococcal vaccinations
Data User’s Guide for the 2021 NIS-Child Public-Use Data File APPENDIX A 

Page 98

4:3:1:3*:3:1:4 The series of 4 or more DTaP vaccinations, 3 or more polio vaccinations, 1 or

(routine Hib) more MCV vaccinations, 3 or 4 Hib vaccinations depending on manufacturer (routine 

recommendation), 3 or more hepatitis B vaccinations, 1 or more varicella 

vaccinations given at age 12 months or older, and 4 or more pneumococcal 

vaccinations

CATI Computer-assisted telephone interviewing

CDC Centers for Disease Control and Prevention

CII Childhood Immunization Initiative 

DOB Date of birth

DTaP Diphtheria and tetanus toxoids and acellular pertussis vaccine adsorbed

DTP Diphtheria and tetanus toxoids and pertussis vaccine

DT Diphtheria and tetanus toxoids adsorbed

H1N Monovalent 2009 H1N1 influenza 

Hep A Hepatitis A vaccine

Hep B Hepatitis B vaccine

Hib Haemophilus influenzae type b conjugate vaccine 

Hib routine Four or more doses of Hib vaccine of any type, or two or more doses of Hib

recommendation vaccine of Merck types followed by one dose of Hib vaccine of any type

Hib shortage Three or more doses of Hib vaccine of any type or two or more doses of Hib

recommendation vaccine of Merck types

 

IAP Immunization Action Plan 

IHQ Immunization history questionnaire

IIS Immunization Information System

IPV Inactivated poliovirus vaccine

MCV Measles-containing vaccine

MMR Measles, mumps, and rubella vaccine

NCHS National Center for Health Statistics

NCIRD National Center for Immunization and Respiratory Diseases

NIS National Immunization Surveys 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File APPENDIX A 

Page 99

NIS-Child National Immunization Survey-Child

NHIS National Health Interview Survey

NIP National Immunization Program

OPV Oral poliovirus vaccine

PCV Pneumococcal conjugate vaccine

PRC Provider Record Check 

PUF Public-use (Data) File

RDD Random digit dialing

RV Rotavirus 

SC Shot card

UTD Up-to-date

VFC Vaccines for Children 

VAR Varicella vaccine
Data User’s Guide for the 2021 NIS-Child Public-Use Data File APPENDIX B 

100

Appendix B: Summary Statistics for Sampling Weights by 

Estimation Area

Table B.1: Distribution of Sampling Weights* for Children with Completed Household 

Interviews, National Immunization Survey - Child, 2021 

State/Estimation Area n Sum Minimum Maximum Mean

Coefficient of 

Variation

U.S. National† 34,863 5,455,448.77 1.00 2,932.40 156.48 161.23

Alabama 510 82,191.03 7.30 488.23 161.16 74.95

Alaska 515 13,037.88 5.18 72.38 25.32 66.40

Arizona 446 118,526.10 2.55 865.15 265.75 76.82

Arkansas 780 51,340.87 6.12 234.99 65.82 88.28

California 1,188 651,665.56 2.42 2,353.79 548.54 112.77

Colorado 475 90,811.71 1.44 890.07 191.18 105.86

Connecticut 755 50,328.52 3.89 183.21 66.66 64.83

Delaware 412 14,582.69 9.07 104.19 35.39 58.64

District of Columbia 712 11,980.55 4.02 52.72 16.83 70.59

Florida 590 326,313.13 1.00 2,932.40 553.07 147.07

Georgia 558 185,776.73 2.39 1,337.44 332.93 100.52

Hawaii 523 23,487.52 6.20 123.33 44.91 60.03

Idaho 630 32,273.25 8.12 174.25 51.23 73.92

Illinois 996 201,225.11 3.51 623.48 202.03 73.87

 IL-City of Chicago 266 46,179.89 4.19 556.41 173.61 77.34

 IL-Rest of State 730 155,045.22 3.51 623.48 212.39 72.09

Indiana 414 116,938.40 6.31 871.13 282.46 69.17

Iowa 440 53,492.66 2.98 412.11 121.57 80.63

Kansas 627 50,896.31 4.01 320.25 81.17 98.22

Kentucky 526 76,698.83 3.33 425.43 145.82 60.82

Louisiana 759 84,472.17 5.62 430.17 111.29 95.25

Maine 434 17,406.57 6.72 89.95 40.11 39.12

Maryland 1,392 103,835.25 2.59 309.92 74.59 106.25

Massachusetts 590 101,402.65 1.97 734.36 171.87 106.60

Michigan 683 155,593.81 6.69 732.18 227.81 84.83

Minnesota 536 97,529.15 2.90 669.63 181.96 92.49

Mississippi 764 51,707.35 5.88 240.93 67.68 93.88

Missouri 730 103,279.04 2.29 505.08 141.48 88.99

Montana 458 17,235.14 6.70 89.87 37.63 49.71

Nebraska 447 35,098.98 7.43 292.92 78.52 93.52

Nevada 744 52,823.46 3.06 220.54 71.00 77.50

New Hampshire 499 17,951.71 5.54 112.16 35.98 61.51

New Jersey 615 147,524.90 5.72 857.17 239.88 89.70

New Mexico 648 31,258.71 4.58 163.59 48.24 86.70

New York 1,436 311,593.10 3.34 1,217.62 216.99 98.50

 NY-City of New York 909 149,894.90 5.64 536.19 164.90 77.25

 NY-Rest of State 527 161,698.20 3.34 1,217.62 306.83 94.37

North Carolina 550 172,330.90 3.73 1,251.50 313.33 115.60

North Dakota 596 14,299.19 4.17 75.06 23.99 88.68

Ohio 866 193,493.81 5.55 737.95 223.43 83.36

Oklahoma 427 71,221.69 3.92 494.24 166.80 63.41

Oregon 498 61,325.15 3.43 369.25 123.14 66.32

Pennsylvania 1,368 195,581.14 3.97 834.82 142.97 147.72
Data User’s Guide for the 2021 NIS-Child Public-Use Data File APPENDIX B 

101

State/Estimation Area n Sum Minimum Maximum Mean

Coefficient of 

Variation

 PA-Philadelphia County 532 30,063.44 5.00 177.26 56.51 65.85

 PA-Rest of State 836 165,517.70 3.97 834.82 197.99 128.12

Rhode Island 473 14,791.28 5.14 94.04 31.27 66.17

South Carolina 520 83,983.61 6.13 492.29 161.51 68.06

South Dakota 581 16,058.09 4.86 84.90 27.64 74.35

Tennessee 783 119,780.83 2.25 565.57 152.98 88.13

Texas 2,060 560,425.20 2.63 1,369.53 272.05 119.18

 TX-Bexar County 486 38,986.74 2.63 234.47 80.22 60.31

 TX-City of Houston 446 71,070.38 5.47 516.41 159.35 83.28

 TX-Rest of State 1,128 450,368.08 6.31 1,369.53 399.26 96.03

Utah 609 67,707.99 3.40 346.92 111.18 72.39

Vermont 557 7,848.52 3.37 37.27 14.09 51.59

Virginia 976 143,589.20 2.53 909.64 147.12 158.02

Washington 803 126,252.72 3.04 551.68 157.23 87.51

West Virginia 419 26,023.07 10.21 158.22 62.11 45.54

Wisconsin 487 91,684.61 13.91 577.91 188.26 63.82

Wyoming 458 8,772.92 3.58 64.37 19.15 79.22

 

Puerto Rico 1,132 27,189.51 1.00 96.23 24.02 109.40

U.S. Virgin Islands 277 1,290.69 1.04 14.24 4.66 62.13

Guam 208 4,504.44 4.42 73.43 21.66 72.42

* Distribution of RDDWT_C_TERR. 

† Excludes U.S. territories. 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File APPENDIX B 

102

Table B.2: Distribution of Sampling Weights* for Children with Adequate Provider Data, 

National Immunization Survey - Child, 2021 

State/Estimation Area n Sum Minimum Maximum Mean

Coefficient 

of Variation

U.S. National† 17,967 5,455,448.77 1.45 5,812.30 303.64 173.57

Alabama 254 82,191.03 14.99 1,179.48 323.59 83.85

Alaska 285 13,037.88 9.45 137.81 45.75 73.77

Arizona 234 118,526.10 5.25 1,917.83 506.52 84.23

Arkansas 413 51,340.87 14.91 443.64 124.31 89.06

California 553 651,665.56 4.74 5,681.87 1178.42 123.22

Colorado 258 90,811.71 2.68 1,707.72 351.98 110.51

Connecticut 409 50,328.52 6.13 386.30 123.05 71.80

Delaware 192 14,582.69 20.17 222.84 75.95 63.10

District of Columbia 334 11,980.55 3.60 128.19 35.87 90.81

Florida 291 326,313.13 1.45 5,812.30 1121.35 145.13

Georgia 266 185,776.73 3.59 2,958.03 698.41 112.68

Hawaii 271 23,487.52 10.32 310.30 86.67 82.26

Idaho 364 32,273.25 8.93 312.42 88.66 85.80

Illinois 530 201,225.11 4.91 1,289.92 379.67 83.44

 IL-City of Chicago 141 46,179.89 6.90 1,238.76 327.52 83.74

 IL-Rest of State 389 155,045.22 4.91 1,289.92 398.57 82.59

Indiana 216 116,938.40 12.00 1,827.47 541.38 75.44

Iowa 228 53,492.66 8.89 839.54 234.62 91.86

Kansas 348 50,896.31 9.69 538.85 146.25 97.79

Kentucky 242 76,698.83 5.24 964.79 316.94 71.76

Louisiana 380 84,472.17 8.52 839.51 222.30 103.94

Maine 235 17,406.57 9.23 198.58 74.07 59.60

Maryland 730 103,835.25 7.62 559.92 142.24 100.84

Massachusetts 335 101,402.65 1.97 1,363.26 302.69 119.78

Michigan 343 155,593.81 8.00 1,687.23 453.63 97.66

Minnesota 260 97,529.15 2.43 1,507.93 375.11 107.65

Mississippi 314 51,707.35 11.07 665.20 164.67 113.83

Missouri 398 103,279.04 15.73 894.38 259.50 92.87

Montana 225 17,235.14 9.03 196.63 76.60 56.44

Nebraska 262 35,098.98 8.63 537.61 133.97 97.21

Nevada 386 52,823.46 10.88 467.45 136.85 86.28

New Hampshire 248 17,951.71 8.30 224.47 72.39 60.63

New Jersey 283 147,524.90 8.27 2,004.35 521.29 95.70

New Mexico 386 31,258.71 6.65 277.05 80.98 88.95

New York 690 311,593.10 3.58 2,621.12 451.58 114.42

 NY-City of New York 437 149,894.90 11.14 1,184.17 343.01 87.32

 NY-Rest of State 253 161,698.20 3.58 2,621.12 639.12 112.73

North Carolina 272 172,330.90 7.91 2,671.99 633.57 122.35

North Dakota 280 14,299.19 3.30 211.74 51.07 111.05

Ohio 442 193,493.81 13.70 1,518.97 437.77 94.46

Oklahoma 192 71,221.69 5.30 1,196.67 370.95 69.09

Oregon 284 61,325.15 4.03 790.72 215.93 84.62

Pennsylvania 677 195,581.14 8.71 1,733.67 288.89 146.92

 PA-Philadelphia County 243 30,063.44 8.71 451.07 123.72 81.99

 PA-Rest of State 434 165,517.70 9.54 1,733.67 381.38 131.53

Rhode Island 247 14,791.28 7.38 194.92 59.88 75.75

South Carolina 235 83,983.61 10.15 1,127.60 357.38 73.13

South Dakota 327 16,058.09 8.67 155.82 49.11 81.89
Data User’s Guide for the 2021 NIS-Child Public-Use Data File APPENDIX B 

103

State/Estimation Area n Sum Minimum Maximum Mean

Coefficient 

of Variation

Tennessee 408 119,780.83 15.89 1,081.96 293.58 96.64

Texas 1,038 560,425.20 7.82 2,866.34 539.91 121.20

 TX-Bexar County 233 38,986.74 12.98 606.80 167.33 69.51

 TX-City of Houston 216 71,070.38 7.82 1,087.33 329.03 82.86

 TX-Rest of State 589 450,368.08 9.53 2,866.34 764.63 101.37

Utah 384 67,707.99 5.82 540.10 176.32 77.40

Vermont 323 7,848.52 5.49 68.40 24.30 59.66

Virginia 520 143,589.20 4.14 1,658.14 276.13 146.58

Washington 478 126,252.72 4.35 946.07 264.13 91.54

West Virginia 210 26,023.07 22.45 283.12 123.92 45.45

Wisconsin 245 91,684.61 21.22 1,190.32 374.22 75.03

Wyoming 242 8,772.92 5.31 132.82 36.25 91.27

 

Puerto Rico 352 27,189.51 1.29 313.68 77.24 111.56

U.S. Virgin Islands 118 1,290.69 1.88 35.16 10.94 83.74

Guam 95 4,504.44 9.20 160.63 47.42 77.28

* Distribution of PROVWT_C_TERR. 

†

 Excludes U.S. territories. 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File APPENDIX C 

104

Appendix C: Flags for Inconsistent Values in the 

Breastfeeding Data 

Two different types of inconsistency can arise in breastfeeding data. The first is that the duration of any 

breastfeeding can exceed the age of the child, and the second is that the age of the child when first fed 

formula can exceed the age of child. BF_ENDR06 stores the duration of any breastfeeding, and 

BF_ENDFL06 flags the inconsistency; BF_FORMR20 stores the age of the child when first fed formula, 

and BF_FORMFL06 flags the inconsistency. 

1. Both BF_ENDR06 and BF_FORMR08 are formulated using the following conversion 

factors: 

if unit=1(days) then BF_ENDR06 = number x 1 

if unit=2(weeks) then BF_ENDR06 = number x 7 

if unit=3(months) then BF_ENDR06 = number x 30.4375 

if unit=4(years) then BF_ENDR06 = number x 365.25 

if unit=1(days) then BF_FORMR20 = number x 1 

if unit=2(weeks) then BF_FORMR20 = number x 7 

if unit=3(months) then BF_FORMR20 = number x 30.4375 

if unit=4(years) then BF_FORMR20 = number x 365.25 

2. Flagging BF_ENDR06 when the duration of any breastfeeding exceeds the age in days with a 

buffer for different units: 

if unit=1(days) flag when BF_ENDR06 > age + 1 

if unit=2(weeks) flag when BF_ENDR06 > age + 3 

if unit=3(months) flag when BF_ENDR06 > age + 15 

if unit=4(years) flag when BF_ENDR06 > age + 182 

The different buffers allow for the impact of rounding durations upward in the specified units (for 

example, 50 days might be reported as 2 months). 

3. Flagging BF_FORMR20 when the age when first fed formula exceeds the age in days with a 

buffer for different units: 

if unit=1(days) flag when BF_FORMR20 > age + 1 

if unit=2(weeks) flag when BF_FORMR20 > age + 3 

if unit=3(months) flag when BF_FORMR20 > age + 15 

if unit=4(years) flag when BF_FORMR20 > age + 182

The different buffers allow for the impact of rounding durations upward in the specified units (for 

example, 50 days might be reported as 2 months).
Data User’s Guide for the 2021 NIS-Child Public-Use Data File APPENDIX D 

105

Appendix D: Programs for Estimation: Examples of the Use 

of SUDAAN, SAS, and R to Estimate Vaccination Coverage 

Rates and Their Standard Errors, and an Example of the 

Production of a Cross-Tabulation and Chart 

I. SUDAAN (RTI, 2008) Page 106

II. SAS (SAS, 2009) Page 119

III. ‘R’ (Lumley, 2022) Page 130 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File APPENDIX D 

106

A. SUDAAN

**********************;

title1 'SUD_IAP.SAS'; 

**********************************************************************

THIS PROGRAM WILL PRODUCE ESTIMATION AREA ESTIMATES AND STANDARD ERRORS FOR 

P_UTD431H314_ROUT_S USING SAS CALLABLE SUDAAN. 

SUDAAN NOTES:

1. ALL VARIABLES USED MUST BE NUMERIC.

2. VARIABLES IN THE SUBGROUP STATEMENT MUST HAVE VALUES 1,2,..K

WHERE K IS THE NUMBER OF LEVELS FOR EACH VARIABLE.

3. DATA MUST BE SORTED ACCORDING TO THE SAMPLE DESIGN VARIABLES

(STRATUM AND PRIMARY SAMPLING UNIT), SPECIFIED IN THE

NEST STATEMENT.

**********************************************************************;

options ps=78 ls=90 obs= max;

libname dd 'c:\nispuf21'; *--- SPECIFY PATH TO SAS DATASET ---*;

libname library 'c:\nispuf21'; *--- IF DATASET WAS CREATED WITH FORMATS

STORED ---*;

*--- PERMANENTLY SPECIFY PATH TO LIBRARY ---*;

*--- OTHERWISE COMMENT THIS STATEMENT OUT ---*;

%let in_file=dd.nispuf21; *--- NAME OF SAS DATASET ---*;

%let estiap=estiap21; * --- ESTIMATION AREA VARIABLE TO USE ---*;

%let wt=provwt_c; * --- WEIGHT TO USE (PROVWT_C is the single-frame cellular phone weight excluding territories. 

Use PROVWT_C_TERR to include territories) --*;

%let strat=stratum; * --- STRATUM VARIABLE TO USE FOR VARIANCE ESTIMATION;

proc format; 

/*

THE FOLLOWING FORMAT WILL BE USED FOR P_UTD431H314_ROUT_S. 

ORIGINAL VALUES OF P_UTD431H314_ROUT_S ARE 1,0.

MUST BE CONVERTED TO 1,2 IN SUDAAN.

*/

value putd431h314f 

1='4:3:1:3:3:1:4 Up-to-Date'

2='Not 4:3:1:3:3:1:4 Up-to-Date'; 

value estiapf

. = "Missing"

0 = "US Total"

1 = "CT"

2 = "MA"

4 = "ME"

5 = "NH"

6 = "RI"

7 = "VT"

8 = "NJ"

10 = "NY-Rest of State"

11 = "NY-City of New York"

12 = "DC"
Data User’s Guide for the 2021 NIS-Child Public-Use Data File APPENDIX D 

107

13 = "DE"

14 = "MD"

16 = "PA-Rest of State"

17 = "PA-Philadelphia County"

18 = "VA"

19 = "WV"

20 = "AL"

22 = "FL"

25 = "GA"

27 = "KY"

28 = "MS"

29 = "NC"

30 = "SC"

31 = "TN"

34 = "IL-Rest of State"

35 = "IL-City of Chicago"

36 = "IN"

38 = "MI"

40 = "MN"

41 = "OH"

44 = "WI"

46 = "AR"

47 = "LA"

49 = "NM"

50 = "OK"

51 = "TX-Rest of State"

54 = "TX-City of Houston"

55 = "TX-Bexar County"

56 = "IA"

57 = "KS"

58 = "MO"

59 = "NE"

60 = "CO"

61 = "MT"

62 = "ND"

63 = "SD"

64 = "UT"

65 = "WY"

66 = "AZ"

68 = "CA"

72 = "HI"

73 = "NV"

74 = "AK"

75 = "ID"

76 = "OR"

77 = "WA"

106 = "Puerto Rico" 

; 

run; 

data sud_file;

set &in_file(keep= seqnumhh seqnumc P_UTD431H314_ROUT_S &estiap &wt &strat);
Data User’s Guide for the 2021 NIS-Child Public-Use Data File APPENDIX D 

108

if P_UTD431H314_ROUT_S=0 then P_UTD431H314_ROUT_S=2; *--- CONVERT P_UTD431H314_ROUT_S=0 TO 

P_UTD431H314_ROUT_S=2 ---*;

nseqnumh=1*seqnumhh; *---CONVERT HOUSEHOLD ID SEQNUMHH FROM CHARACTER TO NUMERIC ---*;

run; 

*=== SORT BY NEST VARIABLES: STRATUM (STRATUM) NSEQNUMH (PRIMARY SAMPLING UNIT) ===*;

proc sort; 

by &strat nseqnumh;

run; 

proc crosstab data=sud_file filetype=sas design=wr;

weight &wt;

nest &strat nseqnumh;

subgroup &estiap P_UTD431H314_ROUT_S ; 

levels 106 2 ; 

tables &estiap * P_UTD431H314_ROUT_S ; 

print nsum wsum rowper serow/style=nchs ;

rtitle "4:3:1:3:3:1:4 ESTIMATES BY ESTIMATION AREA"; 

rformat &estiap estiapf.; 

rformat P_UTD431H314_ROUT_S putd431h314f.; 

output rowper serow/filename=sud_est filetype=sas replace; 

run; 

proc print data=sud_est(where=(P_UTD431H314_ROUT_S=1 and rowper ne .)) noobs label; 

format &estiap estiapf.; 

var &estiap rowper serow ;

label

rowper='Percent 4:3:1:3:3:1:4 Up-to-Date'

serow='Standard Error'

; 

title "4:3:1:3:3:1:4 ESTIMATES BY ESTIMATION AREA"; 

run; 

**********************;

title1 'SUDSTATE.SAS'; 

*************************************************************************

THIS PROGRAM WILL PRODUCE STATE ESTIMATES AND STANDARD ERRORS

FOR P_UTD431H314_ROUT_S USING SAS CALLABLE SUDAAN.

NOTE: THE STATE VARIABLE IS BASED ON FIPSTATE CODES, THERE ARE

NO STATES WITH FIPS CODES 3,7,14,43,52,57-71,73-78. 

SUDAAN NOTES:

1. ALL VARIABLES USED MUST BE NUMERIC.

2. VARIABLES IN THE SUBGROUP STATEMENT MUST HAVE VALUES 1,2,..K

WHERE K IS THE NUMBER OF LEVELS FOR EACH VARIABLE.

3. DATA MUST BE SORTED ACCORDING TO THE SAMPLE DESIGN VARIABLES

(STRATUM AND PRIMARY SAMPLING UNIT), SPECIFIED IN THE

NEST STATEMENT.

*************************************************************************;

options ps=78 ls=90 obs= max;

libname dd 'c:\nispuf21'; *--- SPECIFY PATH TO SAS DATASET ---*;

libname library 'c:\nispuf21'; *--- IF DATASET WAS CREATED WITH FORMATS STORED ---*;
Data User’s Guide for the 2021 NIS-Child Public-Use Data File APPENDIX D 

109

*--- PERMANENTLY SPECIFY PATH TO LIBRARY ---*;

*--- OTHERWISE COMMENT THIS STATEMENT OUT ---*;

%let in_file=dd.nispuf21; *--- NAME OF SAS DATASET ---*;

%let wt=provwt_c; *--- WEIGHT TO USE (PROVWT_C is the single-frame cellular phone weight excluding territories. 

Use PROVWT_C_TERR to include territories) --*;

%let strat=stratum; * --- STRATUM VARIABLE TO USE FOR VARIANCE ESTIMATION;

proc format; 

/*

THE FOLLOWING FORMAT WILL BE USED FOR P_UTD431H314_ROUT_S. 

ORIGINAL VALUES OF P_UTD431H314_ROUT_S ARE 1,0.

MUST BE CONVERTED TO 1,2 IN SUDAAN.

*/

value putd431h314f 

1='4:3:1:3:3:1:4 Up-to-Date'

2='Not 4:3:1:3:3:1:4 Up-to-Date'

; 

value statef

0 ='U.S. Total'

1 ='Alabama '

2 ='Alaska '

4 ='Arizona '

5 ='Arkansas '

6 ='California '

8 ='Colorado '

9 ='Connecticut '

10 ='Delaware '

11 ='District of Columbia'

12 ='Florida '

13 ='Georgia '

15 ='Hawaii '

16 ='Idaho '

17 ='Illinois '

18 ='Indiana '

19 ='Iowa '

20 ='Kansas '

21 ='Kentucky '

22 ='Louisiana '

23 ='Maine '

24 ='Maryland '

25 ='Massachusetts '

26 ='Michigan '

27 ='Minnesota '

28 ='Mississippi '

29 ='Missouri '

30 ='Montana '

31 ='Nebraska '

32 ='Nevada '

33 ='New Hampshire '

34 ='New Jersey '

35 ='New Mexico '

36 ='New York '
Data User’s Guide for the 2021 NIS-Child Public-Use Data File APPENDIX D 

110

37 ='North Carolina '

38 ='North Dakota '

39 ='Ohio '

40 ='Oklahoma '

41 ='Oregon '

42 ='Pennsylvania '

44 ='Rhode Island '

45 ='South Carolina '

46 ='South Dakota '

47 ='Tennessee '

48 ='Texas '

49 ='Utah '

50 ='Vermont '

51 ='Virginia '

53 ='Washington '

54 ='West Virginia '

55 ='Wisconsin '

56 ='Wyoming '

72 ='Puerto Rico ' 

; 

run; 

data sud_file;

set &in_file.(keep= seqnumhh seqnumc P_UTD431H314_ROUT_S state &wt. &strat.); 

if P_UTD431H314_ROUT_S=0 then P_UTD431H314_ROUT_S=2; *** CONVERT P_UTD431H314_ROUT_S=0 TO 

P_UTD431H314_ROUT_S=2 ***;

nseqnumh=1*seqnumhh; *** CONVERT HOUSEHOLD ID SEQNUMH FROM CHARACTER TO NUMERIC ***;

run; 

*=== SORT BY NEST VARIABLES: STRATUM (STRATUM) NSEQNUMH (PRIMARY SAMPLING UNIT) ===*;

proc sort; 

by &strat. nseqnumh;

run; 

proc crosstab data=sud_file filetype=sas design=wr;

weight &wt.; 

nest &strat nseqnumh;

subgroup state P_UTD431H314_ROUT_S ; 

levels 72 2 ; 

tables state * P_UTD431H314_ROUT_S ; 

print nsum wsum rowper serow/style=nchs ;

rtitle "4:3:1:3:3:1:4 ESTIMATES BY STATE"; 

rformat state statef.; 

rformat P_UTD431H314_ROUT_S putd431h314f.; 

output rowper serow / filename=sud_est2 filetype=sas replace;

run; 

*** EXCLUDE 3,7,14,43,52, 57-71, 73-78 THERE ARE NO STATES WITH THESE FIPS CODES *** ;

option spool; 

proc print data=sud_est2(where=(P_UTD431H314_ROUT_S=1 and rowper ne . 

& state notin (3,7,14,43,52) and not(57<=state<=71) and not (73<=state<=78)))label noobs; 

format state statef.; 

var state rowper serow ;
Data User’s Guide for the 2021 NIS-Child Public-Use Data File APPENDIX D 

111

label

rowper='Percent 4:3:1:3:3:1:4 Up-to-Date'

serow='Standard Error'

; 

title "4:3:1:3:3:1:4 ESTIMATES BY STATE"; 

run; 

option nospool; 

**********************;

title1 'PROG_3.SAS'; 

*************************************************************************

THIS PROGRAM WILL PRODUCE A TABLE OF HAD_CPOX BY STATE FOR ALL RDD

COMPLETES USING RDDWT_C. THE PROGRAM USES SAS CALLABLE SUDAAN.

SUDAAN NOTES:

1. ALL VARIABLES USED MUST BE NUMERIC.

2. VARIABLES IN THE SUBGROUP STATEMENT MUST HAVE VALUES 1,2,..K

WHERE K IS THE NUMBER OF LEVELS FOR EACH VARIABLE.

3. DATA MUST BE SORTED ACCORDING TO THE SAMPLE DESIGN VARIABLES

(STRATUM AND PRIMARY SAMPLING UNIT), SPECIFIED IN THE

NEST STATEMENT.

*************************************************************************;

options ps=78 ls=90 obs= max;

libname dd 'c:\nispuf21'; *--- SPECIFY PATH TO SAS DATASET ---*;

libname library 'c:\nispuf21'; *--- IF DATASET WAS CREATED WITH FORMATS STORED ---*;

*--- PERMANENTLY SPECIFY PATH TO LIBRARY ---*;

*--- OTHERWISE COMMENT THIS STATEMENT OUT ---*;

%let in_file=dd.nispuf21; *--- NAME OF SAS DATASET ---*;

%let wt=rddwt_c; * --- WEIGHT TO USE (RDDWT_C is the single-frame cellular phone weight excluding territories. 

Use RDDWT_C_TERR to include territories) ---*;

%let strat=stratum; * --- STRATUM VARIABLE TO USE FOR VARIANCE ESTIMATION;

proc format; 

/*

THE FOLLOWING FORMAT WILL BE USED FOR HAD_CPOX. 

*/

value hadcpoxf

1='Yes'

2='No'

; 

value statef

0 ='U.S. Total '

1 ='Alabama '

2 ='Alaska '

4 ='Arizona '

5 ='Arkansas '

6 ='California '

8 ='Colorado '

9 ='Connecticut '

10 ='Delaware '

11 ='District of Columbia'
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12 ='Florida '

13 ='Georgia '

15 ='Hawaii '

16 ='Idaho '

17 ='Illinois '

18 ='Indiana '

19 ='Iowa '

20 ='Kansas '

21 ='Kentucky '

22 ='Louisiana '

23 ='Maine '

24 ='Maryland '

25 ='Massachusetts '

26 ='Michigan '

27 ='Minnesota '

28 ='Mississippi '

29 ='Missouri '

30 ='Montana '

31 ='Nebraska '

32 ='Nevada '

33 ='New Hampshire '

34 ='New Jersey '

35 ='New Mexico '

36 ='New York '

37 ='North Carolina '

38 ='North Dakota '

39 ='Ohio '

40 ='Oklahoma '

41 ='Oregon '

42 ='Pennsylvania '

44 ='Rhode Island '

45 ='South Carolina '

46 ='South Dakota '

47 ='Tennessee '

48 ='Texas '

49 ='Utah '

50 ='Vermont '

51 ='Virginia '

53 ='Washington '

54 ='West Virginia '

55 ='Wisconsin '

56 ='Wyoming '

72 ='Puerto Rico ' 

; 

run; 

data sud_file;

set &in_file.(keep= seqnumhh seqnumc state had_cpox &wt. &strat.); 

nseqnumh=1*seqnumhh; *** CONVERT HOUSEHOLD ID SEQNUMH FROM CHARACTER TO NUMERIC ***;

run; 

*=== SORT BY NEST VARIABLES: STRATUM (STRATUM) NSEQNUMH (PRIMARY SAMPLING UNIT) ===*;

proc sort; 
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by &strat. nseqnumh;

run; 

proc crosstab data=sud_file filetype=sas design=wr;

weight &wt.; 

nest &strat. nseqnumh;

subgroup state had_cpox ;

levels 72 2 ; 

tables state * had_cpox ;

print nsum wsum rowper serow/style=nchs ;

rtitle "HAD_CPOX ESTIMATES BY STATE"; 

rtitle "WEIGHT = &WT"; 

rformat state statef.; 

rformat had_cpox hadcpoxf.; 

output rowper serow / filename=sud_est3 filetype=sas replace; 

run; 

*** EXCLUDE 3,7,14,43,52, 57-71, 73-78 THERE ARE NO STATES WITH THESE FIPS CODES *** ;

option spool; 

proc print data=sud_est3(where=(had_cpox=1 and rowper ne .

& state notin (3,7,14,43,52) and not (57<=state<=71) and not (73<=state<=78))) label noobs; 

format state statef.; 

var state rowper serow ;

label

rowper='Percent HAD_CPOX = Yes'

serow='Standard Error'

; 

title "CHILD HAD CHICKEN POX BY STATE"; 

run; 

option nospool; 

**********************;

title1 'PROG_4.SAS'; 

*************************************************************************

TABLE OF P_UTD431H314_ROUT_S BY INCPOV1 BY RACE_K. SAVE % UTD

ESTIMATES (NOT S.E.'S) FOR USE IN THE PROGRAM CHART_4.

THIS PROGRAM WILL PRODUCE ESTIMATES USING SAS CALLABLE SUDAAN.

SUDAAN NOTES:

1. ALL VARIABLES USED MUST BE NUMERIC.

2. VARIABLES IN THE SUBGROUP STATEMENT MUST HAVE VALUES 1,2,..K

WHERE K IS THE NUMBER OF LEVELS FOR EACH VARIABLE.

3. DATA MUST BE SORTED ACCORDING TO THE SAMPLE DESIGN VARIABLES

(STRATUM AND PRIMARY SAMPLING UNIT), SPECIFIED IN THE

NEST STATEMENT.

*************************************************************************;

options ps=78 ls=90 obs= max;

libname dd 'c:\nispuf21'; *--- SPECIFY PATH TO SAS DATASET ---*;

libname library 'c:\nispuf21'; *--- IF DATASET WAS CREATED WITH FORMATS

STORED ---*;

*--- PERMANENTLY SPECIFY PATH TO LIBRARY ---*;
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*--- OTHERWISE COMMENT THIS STATEMENT OUT ---*;

libname out 'c:\nispuf21'; *--- SPECIFY THE PATH FOR WHERE YOU WANT THE CHART OUTPUT TO GO ---*;

%let in_file=dd.nispuf21; *--- NAME OF SAS DATASET ---*;

%let wt=provwt_c; *--- WEIGHT TO USE (PROVWT_C is the single-frame cellular phone weight excluding territories. 

Use PROVWT_C_TERR to include territories) ---*;

%let strat=stratum; * --- STRATUM VARIABLE TO USE FOR VARIANCE ESTIMATION;

%let qtr_lab=Q1/2021 - Q4/2021; *NIS 4 QUARTER PERIOD*;

proc format; 

/*

THE FOLLOWING FORMAT WILL BE USED FOR P_UTD431H314_ROUT_S. 

ORIGINAL VALUES OF P_UTD431H314_ROUT_S ARE 1,0.

MUST BE CONVERTED TO 1,2 IN SUDAAN.

*/

value putd431h314f

1='4:3:1:3:3:1:4 Up-to-Date'

2='Not 4:3:1:3:3:1:4 Up-to-Date'

; 

VALUE race_kf

1 = "WHITE ONLY"

2 = "BLACK ONLY"

3 = "OTHER AND MULTIPLE RACE"

; 

VALUE incpvr2f

1 = "ABOVE, > $75,000"

2 = "ABOVE, <= $75,000"

3 = "BELOW"

4 = "UNKNOWN"

; 

value statef

0 ='U.S. Total '

1 ='Alabama '

2 ='Alaska '

4 ='Arizona '

5 ='Arkansas '

6 ='California '

8 ='Colorado '

9 ='Connecticut '

10 ='Delaware '

11 ='District of Columbia '

12 ='Florida '

13 ='Georgia '

15 ='Hawaii '

16 ='Idaho '

17 ='Illinois '

18 ='Indiana '

19 ='Iowa '

20 ='Kansas '

21 ='Kentucky '

22 ='Louisiana '

23 ='Maine '
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24 ='Maryland '

25 ='Massachusetts '

26 ='Michigan '

27 ='Minnesota '

28 ='Mississippi '

29 ='Missouri '

30 ='Montana '

31 ='Nebraska '

32 ='Nevada '

33 ='New Hampshire '

34 ='New Jersey '

35 ='New Mexico '

36 ='New York '

37 ='North Carolina '

38 ='North Dakota '

39 ='Ohio '

40 ='Oklahoma '

41 ='Oregon '

42 ='Pennsylvania '

44 ='Rhode Island '

45 ='South Carolina '

46 ='South Dakota '

47 ='Tennessee '

48 ='Texas '

49 ='Utah '

50 ='Vermont '

51 ='Virginia '

53 ='Washington '

54 ='West Virginia '

55 ='Wisconsin '

56 ='Wyoming '

72 ='Puerto Rico ' 

; 

run; 

data sud_file;

set &in_file(keep= seqnumhh seqnumc P_UTD431H314_ROUT_S race_k incpov1 &wt &strat);

nseqnumh=1*seqnumhh; *** CONVERT HOUSEHOLD ID SEQNUMH FROM CHARACTER TO NUMERIC ***;

if P_UTD431H314_ROUT_S=0 then P_UTD431H314_ROUT_S=2; *** CONVERT P_UTD431H314_ROUT_S=0 TO 

P_UTD431H314_ROUT_S=2 ***;

run; 

*=== SORT BY NEST VARIABLES: STRATUM (STRATUM) NSEQNUMH (PRIMARY SAMPLING UNIT) ===*;

proc sort; 

by &strat nseqnumh;

run; 

proc freq; 

tables P_UTD431H314_ROUT_S incpov1 race_k;

title1 "Table 4A. &qtr_lab: Unweighted Frequencies"; 

run; 

proc crosstab data=sud_file filetype=sas design=wr;
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116

weight &wt;

nest &strat nseqnumh;

subgroup incpov1 race_k P_UTD431H314_ROUT_S ; 

levels 4 3 2; 

tables (incpov1 * race_k * P_UTD431H314_ROUT_S) ;

print nsum wsum rowper="4:3:1:3:3:1:4 Up-to-Date (ROWPER)"

serow="Standard Error (SEROW)" /style=nchs ;

rtitle "Table 4B. &qtr_lab, Percent 4:3:1:3:3:1:4 Up-to-Date and Estimated Standard Errors"; 

rtitle "WEIGHT = &WT"; 

rformat P_UTD431H314_ROUT_S putd431h314f.; 

rformat incpov1 incpvr2f.; 

rformat race_k race_kf.; 

output rowper serow / filename=sud_est4 filetype=sas replace; 

run; 

data out.sud_est4;

set sud_est4(where=(P_UTD431H314_ROUT_S=1 & incpov1 > 0 & race_k > 0)); 

keep incpov1 race_k rowper serow;

label rowper='4:3:1:3:3:1:4 Up-to-Date'; 

format rowper 5.2; 

format serow 5.2; 

run; 

proc print data=out.sud_est4 label; 

format race_k race_kf.; 

format incpov1 incpvr2f.; 

title "Table 4B. &qtr_lab, 4:3:1:3:3:1:4 ESTIMATES AND STANDARD ERRORS BY INCPOV1 BY RACE_K"; 

run; 

**********************;

title1 'SAS_GRAPH_4.SAS'; 

*************************************************************************

THIS PROGRAM BUILDS OFF OF THE PROGRAM SAS_PROG_4. IT PRODUCES A CHART OF

P_UTD431H314_ROUT_S BY INCPOV1 BY RACE_K. IT CREATES A BAR CHART IN SAS GRAPH FOR

THE 4X3 = 12 CELLS. THE OUTPUT OF THE FOLLOWING EXAMPLE IS ATTACHED AT THE

END.

*************************************************************************;

options ps=78 ls=90 obs= max;

libname dd 'c:\nispuf21'; *--- SPECIFY PATH TO SAS DATASET ---*;

%let out='c:\nispuf21'; *--- SPECIFY THE PATH FOR WHERE YOU WANT THE CHART

OUTPUT TO GO ---*;

%let in_file=dd.sud_est4; *--- NAME OF SAS DATASET OUTPUT FROM PROG_4 ---*;

%let qtr_lab=Q1/2021 - Q4/2021; *NIS 4 QUARTER PERIOD*;

proc format; 

value incpvr2f

1 = "ABOVE, > $75,000"

2 = "ABOVE, <= $75,000"

3 = "BELOW"
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4 = "UNKNOWN"

; 

value race_kf

1 = "WHITE ONLY"

2 = "BLACK ONLY"

3 = "OTHER/MULT RACE"

; 

run; 

data sud_est4;

set &in_file.; 

format rowper 3.

RACE_K race_kf.

INCPOV1 incpvr2f.

; 

label

RACE_K = 'Race of Child'

INCPOV1 = 'Poverty Status'

; 

filename odsout &out.; 

ods listing close; 

/* SET THE GRAPHICS ENVIRONMENT */

goptions reset=global gunit=pct border

ftext=swissb htitle=4 htext=1.5

device=gif

; 

ods html body='graph_4_sud.html' path=odsout;

run; 

title1 h=12pt "Percentage of Children Up-to-Date with Vaccine Series 4:3:1:3:3:1:4"; 

title2 h=12pt "by Race and Poverty Status, National Immunization Survey - Child, 2021"; 

footnote j=r 'graph_4sud'; 

proc sgplot data=sud_est4;

styleattrs datacolors=(wheat lightpink forestgreen) datacontrastcolors=(wheat lightpink forestgreen) 

datalinepatterns=(solid);

vbar INCPOV1 / response=rowper group=RACE_K groupdisplay=cluster stat=mean barwidth=0.8; 

xaxis display=(noticks);

yaxis grid; 

keylegend / across=1 position=top;

run; 

ods html close; 

ods listing; 
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Data User’s Guide for the 2021 NIS-Child Public-Use Data File APPENDIX D 

119

B. SAS 

**********************;

title1 'SAS_IAP.SAS'; 

**********************************************************************

THIS PROGRAM WILL PRODUCE ESTIMATION AREA ESTIMATES AND STANDARD ERRORS

FOR P_UTD431H314_ROUT_S USING SAS.

**********************************************************************;

options ps=78 ls=90 obs= max;

libname dd 'c:\nispuf21'; *--- SPECIFY PATH TO SAS DATASET ---*;

libname library 'c:\nispuf21'; *--- IF DATASET WAS CREATED WITH FORMATS STORED ---*;

*--- PERMANENTLY SPECIFY PATH TO LIBRARY ---*;

*--- OTHERWISE COMMENT THIS STATEMENT OUT ---*;

%let in_file=dd.nispuf21; *--- NAME OF SAS DATASET ---*;

%let estiap=estiap21; * --- ESTIMATION AREA VARIABLE TO USE ---*;

%let wt=provwt_c; * --- WEIGHT TO USE (PROVWT_C is the single-frame cellular phone weight excluding territories. 

Use PROVWT_C_TERR to include territories) --*;

%let strat=stratum; * --- STRATUM VARIABLE TO USE FOR VARIANCE ESTIMATION;

proc format; 

value putd431h314f 

0='Not 4:3:1:3:3:1:4 Up-To-Date'

1='4:3:1:3:3:1:4 Up-To-Date'; 

value estiapf

. = "Missing"

0 = "US Total"

1 = "CT"

2 = "MA"

4 = "ME"

5 = "NH"

6 = "RI"

7 = "VT"

8 = "NJ"

10 = "NY-Rest of State"

11 = "NY-City of New York"

12 = "DC"

13 = "DE"

14 = "MD"

16 = "PA-Rest of State"

17 = "PA-Philadelphia County"

18 = "VA"

19 = "WV"

20 = "AL"

22 = "FL"

25 = "GA"

27 = "KY"

28 = "MS"

29 = "NC"
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30 = "SC"

31 = "TN"

34 = "IL-Rest of State"

35 = "IL-City of Chicago"

36 = "IN"

38 = "MI"

40 = "MN"

41 = "OH"

44 = "WI"

46 = "AR"

47 = "LA"

49 = "NM"

50 = "OK"

51 = "TX-Rest of State"

54 = "TX-City of Houston"

55 = "TX-Bexar County"

56 = "IA"

57 = "KS"

58 = "MO"

59 = "NE"

60 = "CO"

61 = "MT"

62 = "ND"

63 = "SD"

64 = "UT"

65 = "WY"

66 = "AZ"

68 = "CA"

72 = "HI"

73 = "NV"

74 = "AK"

75 = "ID"

76 = "OR"

77 = "WA"

106 = "Puerto Rico" 

; 

run; 

data sas_file;

set &in_file.(keep= seqnumhh seqnumc P_UTD431H314_ROUT_S &estiap. &wt. &strat.);

run; 

proc sort data = sas_file;

by &estiap.; 

run; 

title1 '4:3:1:3:3:1:4 ESTIMATES BY ESTIMATION AREA'; 

ods output Statistics=sas_est;

proc surveymeans data = sas_file nobs sum mean stderr;

stratum &strat.; 

cluster seqnumhh;

weight &wt.; 

class P_UTD431H314_ROUT_S; 
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var P_UTD431H314_ROUT_S; 

by &estiap.; 

format P_UTD431H314_ROUT_S putd431h314f.; 

format &estiap. estiapf.; 

run; 

data sas_est;

set sas_est;

mean = mean*100; *CONVERT TO PERCENT ESTIMATES;

stderr = stderr*100; 

run; 

proc print data=sas_est(where=(varlevel='4:3:1:3:3:1:4 Up-To-Date')) noobs

label; 

format &estiap. estiapf.; 

format mean stderr 5.2; 

var &estiap. mean stderr;

label

mean='Percent 4:3:1:3:3:1:4 Up-to-Date'

stderr='Standard Error'; 

title "4:3:1:3:3:1:4 ESTIMATES BY ESTIMATION AREA"; 

run; 

**********************;

title1 'SASSTATE.SAS'; 

**********************************************************************

THIS PROGRAM WILL PRODUCE STATE ESTIMATES AND STANDARD ERRORS

FOR P_UTD431H314_ROUT_S USING SAS.

NOTE: THE STATE VARIABLE IS BASED ON FIPSTATE CODES, THERE ARE

NO STATES WITH FIPS CODES 3,7,14,43,52,57-71,73-78. 

**********************************************************************;

options ps=78 ls=90 obs= max;

libname dd 'c:\nispuf21'; *--- SPECIFY PATH TO SAS DATASET ---*;

libname library 'c:\nispuf21'; *--- IF DATASET WAS CREATED WITH FORMATS

STORED ---*;

*--- PERMANENTLY SPECIFY PATH TO LIBRARY ---*;

*--- OTHERWISE COMMENT THIS STATEMENT OUT ---*;

%let in_file=dd.nispuf21; *--- NAME OF SAS DATASET ---*;

%let wt=provwt_c; * --- WEIGHT TO USE (PROVWT_C is the single-frame cellular phone weight excluding territories. 

Use PROVWT_C_TERR to include territories) --*;

%let strat=stratum; * --- STRATUM VARIABLE TO USE FOR VARIANCE ESTIMATION;

proc format; 

value putd431h314f

0='Not 4:3:1:3:3:1:4 Up-To-Date'

1='4:3:1:3:3:1:4 Up-To-Date'; 

value statef

. ="Missing"

0 ='U.S. Total '

1 ='Alabama '
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-Child Public-Use Data FileAPPENDIX D 

122

2 ='Alaska ' 4 ='Arizona ' 5 ='Arkansas ' 6 ='California ' 8 ='Colorado ' 9 ='Connecticut '

10 ='Delaware '

11 ='District of Columbia '

12='Florida '

13 ='Georgia '

15 ='Hawaii '

16='Idaho '

17 ='Illinois '

18 ='Indiana '

19 ='Iowa '

20 ='Kansas '

21 ='Kentucky '

22='Louisiana '

23 ='Maine '

24 ='Maryland '

25 ='Massachusetts '

26 ='Michigan '

27 ='Minnesota '

28 ='Mississippi '

29 ='Missouri '

30='Montana '

31 ='Nebraska '

32 ='Nevada '

33 ='New Hampshire '

34 ='New Jersey '

35 ='New Mexico '

36 ='New York '

37 ='North Carolina '

38 ='North Dakota '

39 ='Ohio '

40 ='Oklahoma '

41 ='Oregon '

42 ='Pennsylvania '

44 ='Rhode Island '

45 ='South Carolina '

46 ='South Dakota '

47 ='Tennessee '

48 ='Texas '

49 ='Utah '

50 ='Vermont '

51 ='Virginia '

53 ='Washington '

54 ='West Virginia '

55 ='Wisconsin '

56 ='Wyoming '

72 ='Puerto Rico ' 

; 

run; 
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data sas_file;

set &in_file(keep= seqnumhh seqnumc P_UTD431H314_ROUT_S state &wt &strat);

run; 

proc sort data = sas_file;

by state;

title1 '4:3:1:3:3:1:4 ESTIMATES BY STATE'; 

ods output Statistics=sas_est2;

run; 

proc surveymeans data = sas_file nobs sum mean stderr;

stratum &strat;

cluster seqnumhh;

weight &wt;

class P_UTD431H314_ROUT_S; 

var P_UTD431H314_ROUT_S; 

by state;

format P_UTD431H314_ROUT_S putd431h314f.; 

format state statef.; 

run; 

data sas_est2;

set sas_est2;

mean = mean*100; *CONVERT TO PERCENT ESTIMATES;

stderr = stderr*100; 

run; 

proc print data=sas_est2(where=(varlevel='4:3:1:3:3:1:4 Up-To-Date')) noobs

label; 

format state statef.; 

format mean stderr 5.2; 

var state mean stderr;

label

mean='Percent 4:3:1:3:3:1:4 Up-to-Date'

stderr='Standard Error'; 

title "4:3:1:3:3:1:4 ESTIMATES BY STATE"; 

run; 

**********************;

title1 'SAS_PROG_3.SAS'; 

*************************************************************************

THIS PROGRAM WILL PRODUCE A TABLE OF HAD_CPOX BY STATE FOR ALL RDD

COMPLETES USING RDDWT. THE PROGRAM USES SAS.

*************************************************************************;

options ps=78 ls=90 obs= max;

libname dd 'c:\nispuf21'; *--- SPECIFY PATH TO SAS DATASET ---*;

libname library 'c:\nispuf21'; *--- IF DATASET WAS CREATED WITH FORMATS

STORED ---*;

*--- PERMANENTLY SPECIFY PATH TO LIBRARY ---*;

*--- OTHERWISE COMMENT THIS STATEMENT OUT ---*;
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%let in_file=dd.nispuf21; *--- NAME OF SAS DATASET ---*;

%let wt=rddwt_c; *--- WEIGHT TO USE (RDDWT_C is the single-frame cellular phone weight excluding territories) ---

*;

%let strat=stratum; * --- STRATUM VARIABLE TO USE FOR VARIANCE ESTIMATION;

proc format; 

value hadcpoxf

1='Yes'

2='No'

; 

value statef

0 ='U.S. Total '

1 ='Alabama '

2 ='Alaska '

4 ='Arizona '

5 ='Arkansas '

6 ='California '

8 ='Colorado '

9 ='Connecticut '

10 ='Delaware '

11 ='District of Columbia '

12 ='Florida '

13 ='Georgia '

15 ='Hawaii '

16 ='Idaho '

17 ='Illinois '

18 ='Indiana '

19 ='Iowa '

20 ='Kansas '

21 ='Kentucky '

22 ='Louisiana '

23 ='Maine '

24 ='Maryland '

25 ='Massachusetts '

26 ='Michigan '

27 ='Minnesota '

28 ='Mississippi '

29 ='Missouri '

30 ='Montana '

31 ='Nebraska '

32 ='Nevada '

33 ='New Hampshire '

34 ='New Jersey '

35 ='New Mexico '

36 ='New York '

37 ='North Carolina '

38 ='North Dakota '

39 ='Ohio '

40 ='Oklahoma '

41 ='Oregon '

42 ='Pennsylvania '

44 ='Rhode Island '
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45 ='South Carolina '

46 ='South Dakota '

47 ='Tennessee '

48 ='Texas '

49 ='Utah '

50 ='Vermont '

51 ='Virginia '

53 ='Washington '

54 ='West Virginia '

55 ='Wisconsin '

56 ='Wyoming '

72 ='Puerto Rico ' 

; 

run; 

data sas_file;

set &in_file.(keep= seqnumhh seqnumc state had_cpox &wt. &strat.); 

run; 

proc sort data = sas_file;

by state;

title1 'HAD_CPOX ESTIMATES BY STATE'; 

ods output Statistics=sas_est3;

run; 

proc surveymeans data = sas_file nobs sum mean stderr;

stratum &strat.; 

cluster seqnumhh;

weight &wt.; 

class had_cpox;

var had_cpox;

by state;

format had_cpox hadcpoxf.; 

format state statef.; 

run; 

data sas_est3;

set sas_est3;

mean = mean*100; *CONVERT TO PERCENT ESTIMATES;

stderr = stderr*100; 

run; 

proc print data=sas_est3(where=(varlevel='Yes')) noobs label; 

format state statef.; 

format mean stderr 5.2; 

var state mean stderr;

label

mean='Percent HAD_CPOX = Yes'

stderr='Standard Error'; 

title "CHILD HAD CHICKEN POX BY STATE"; 

run; 
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**********************;

title1 'SAS_PROG_4.SAS'; 

*************************************************************************

TABLE OF P_UTD431H314_ROUT_S BY INCPOV1 BY RACE_K. SAVE % UTD

ESTIMATES (NOT S.E.'S) FOR USE IN THE PROGRAM SAS_GRAPH_4.

THIS PROGRAM WILL PRODUCE ESTIMATES USING SAS.

*************************************************************************;

options ps=78 ls=90 obs= max;

libname dd 'c:\nispuf21'; *--- SPECIFY PATH TO SAS DATASET ---*;

libname library 'c:\nispuf21'; *--- IF DATASET WAS CREATED WITH FORMATS

STORED ---*;

*--- PERMANENTLY SPECIFY PATH TO LIBRARY ---*;

*--- OTHERWISE COMMENT THIS STATEMENT OUT ---*;

libname out 'c:\nispuf21'; *--- SPECIFY THE PATH FOR 

WHERE YOU WANT THE CHART OUTPUT TO GO ---*;

%let in_file=dd.nispuf21; *--- NAME OF SAS DATASET ---*;

%let wt=provwt_c; *--- WEIGHT TO USE (PROVWT_C is the single-frame cellular phone weight excluding territories. 

Use PROVWT_C_TERR to include territories) --*;

%let strat=stratum; * --- STRATUM VARIABLE TO USE FOR VARIANCE ESTIMATION;

%let qtr_lab=Q1/2021 - Q4/2021; *NIS 4 QUARTER PERIOD*;

proc format; 

value putd431h314f

0='Not 4:3:1:3:3:1:4 Up-To-Date'

1='4:3:1:3:3:1:4 Up-To-Date'

; 

value race_kf

1 = "WHITE ONLY"

2 = "BLACK ONLY"

3 = "OTHER AND MULTIPLE RACE"

; 

value incpvr2f

1 = "ABOVE, > $75,000"

2 = "ABOVE, <= $75,000"

3 = "BELOW"

4 = "UNKNOWN"

; 

run; 

data sas_file;

set &in_file.(keep= seqnumhh seqnumc P_UTD431H314_ROUT_S race_k incpov1 &wt. &strat.); 

run; 

proc sort data = sas_file;

by incpov1 race_k;

run; 

proc freq; 

tables P_UTD431H314_ROUT_S incpov1 race_k;

title1 "Table 4A. &qtr_lab: Unweighted Frequencies"; 
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run; 

data sas_file;

set sas_file;

if P_UTD431H314_ROUT_S < 0 | incpov1 < 0 | race_k < 0 | &wt. < 0 then delete; 

run; 

proc surveymeans data = sas_file nobs sum mean stderr;

ods output Domain=sas_est4;

stratum &strat.; 

cluster seqnumhh;

weight &wt.; 

class P_UTD431H314_ROUT_S; 

var P_UTD431H314_ROUT_S; 

domain incpov1*race_k;

format P_UTD431H314_ROUT_S putd431h314f.; 

format incpov1 incpvr2f.; 

format race_k race_kf.; 

run; 

data sas_est4;

set sas_est4;

mean = mean*100; *CONVERT TO PERCENT ESTIMATES;

stderr = stderr*100; 

run; 

proc print data=sas_est4(where=(varlevel='4:3:1:3:3:1:4 Up-To-Date')) noobs

label; 

format incpov1 incpvr2f.; 

format race_k race_kf.; 

format mean stderr 5.2; 

var incpov1 race_k mean stderr;

label

mean='4:3:1:3:3:1:4 Up-To-Date'

stderr='Standard Error'; 

title1 "Table 4B. &qtr_lab, 4:3:1:3:3:1:4 ESTIMATES AND STANDARD ERRORS BY INCPOV1 BY RACE_K"; 

run; 

data out.sas_est4;

set sas_est4(where=(varlevel='4:3:1:3:3:1:4 Up-To-Date')); 

keep incpov1 race_k mean;

label mean='4:3:1:3:3:1:4 Up-to-Date'; 

format mean 5.2; 

run; 

**********************;

title1 'SAS_GRAPH_4.SAS'; 

*************************************************************************

THIS PROGRAM BUILDS OFF OF THE PROGRAM SAS_PROG_4. IT PRODUCES A CHART OF

P_UTD431H314_ROUT_S BY INCPOV1 BY RACE_K. IT CREATES A BAR CHART IN SAS GRAPH FOR

THE 4X3 = 12 CELLS. THE OUTPUT OF THE FOLLOWING EXAMPLE IS ATTACHED AT THE

END.
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128

*************************************************************************;

options ps=78 ls=90 obs= max;

libname dd 'c:\nispuf21'; *--- SPECIFY PATH TO SAS DATASET ---*;

%let out='c:\nispuf21'; *--- SPECIFY THE PATH FOR WHERE YOU WANT THE CHART

OUTPUT TO GO ---*;

%let in_file=dd.sas_est4; *--- NAME OF SAS DATASET OUTPUT FROM PROG_4 ---*;

%let qtr_lab=Q1/2021 - Q4/2021; *NIS 4 QUARTER PERIOD*;

proc format; 

value incpvr2f

1 = "ABOVE, > $75,000"

2 = "ABOVE, <= $75,000"

3 = "BELOW"

4 = "UNKNOWN"

; 

value race_kf

1 = "WHITE ONLY"

2 = "BLACK ONLY"

3 = "OTHER/MULT RACE"

; 

run; 

data sas_est4;

set &in_file.; 

format mean 3.

race_k race_kf.

incpov1 incpvr2f.

; 

label

race_k = 'Race of Child'

incpov1 = 'Poverty Status'

; 

filename odsout &out.; 

ods listing close; 

/* SET THE GRAPHICS ENVIRONMENT */

goptions reset=global gunit=pct border

ftext=swissb htitle=4 htext=1.5

device=gif

; 

ods html body='graph_4.html' path=odsout;

run; 

title1 h=12pt "Percentage of Children Up-to-Date with Vaccine Series 4:3:1:3:3:1:4 "; 

title2 h=12pt "by Race and Poverty Status, National Immunization Survey - Child, 2021"; 

footnote j=r 'graph_4'; 

proc sgplot data=sas_est4;

styleattrs datacolors=(wheat lightpink forestgreen) datacontrastcolors=(wheat lightpink forestgreen) 

datalinepatterns=(solid);

vbar INCPOV1 / response=mean group=RACE_K groupdisplay=cluster stat=mean barwidth=0.8; 
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129

xaxis display=(noticks);

yaxis grid; 

keylegend / across=1 position=top;

run; 

ods html close; 

ods listing; 
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130

C. ‘R’ 

###################### 

title <- "R_IAP.R" 

###################################################################### 

#THIS PROGRAM WILL PRODUCE ESTIMATION AREA ESTIMATES AND STANDARD ERRORS

#FOR P_UTD431H314_ROUT_S USING R.

# 

#R NOTES:

#1. R IS CASE SENSITIVE.

#2. A FILE PATH IS SEPERATED BY SLASH(/)

###################################################################### 

library(survey) #TO USE svydesign(), svymean(), and svyby()

library(Hmisc) #TO USE prn()

dd <- "c:/nispuf21" #"path-to-dataset"

#--- NAME OF R DATASET ---# 

in.file <- paste(dd,"/NISPUF21.RData",sep="")

#---READ R DATASET---# 

load(in.file) 

#---FORMAT---# 

UTD431H314levels=c(0,1)

UTD431H314labels=c("NOT 4:3:1:3:3:1:4 UTD", "4:3:1:3:3:1:4 UTD")

ESTIAPlevels=c(0, 1, 2, 4, 5, 6, 7, 8, 10, 11, 12, 13, 14, 16, 17, 18, 19, 20, 22, 25, 27, 28, 29, 30, 31, 34, 35, 36, 38, 40, 41, 44, 46, 47, 49, 50, 51, 54, 

55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 68, 72, 73, 74, 75, 76, 77, 106) 

ESTIAPlabels=c("US Total", "CT", "MA", "ME", "NH", "RI", "VT", "NJ", "NY-Rest of State", "NY-City of New York", "DC", "DE", "MD", "PARest of State", "PA-Philadelphia County", "VA", "WV", "AL", "FL", "GA", "KY", "MS", "NC", "SC", "TN", "IL-Rest of State", "IL-City of 

Chicago", "IN", "MI", "MN", "OH", "WI", "AR", "LA", "NM", "OK", "TX-Rest of State", "TX-City of Houston", "TX-Bexar County", "IA", "KS", 

"MO", "NE", "CO", "MT", "ND", "SD", "UT", "WY", "AZ", "CA", "HI", "NV", "AK", "ID", "OR", "WA", "Puerto Rico") 

#---PROVWT_C WILL BE USED AS A WEIGHT (PROVWT_C IS THE SINGLE-FRAME CELLULAR PHONE WEIGHT EXCLUDING 

TERRITORIES; USE PROVWT_C_TERR TO INCLUDE TERRITORIES)---# 

#---STRATUM WILL BE USED AS A STRATUM VARIABLE FOR VARIANCE ESTIMATION ---# 

R_FILE <- subset(NISPUF21, select=c(SEQNUMHH, SEQNUMC, P_UTD431H314_ROUT_S, ESTIAP21, 

PROVWT_C, STRATUM))

names(R_FILE) <- c("SEQNUMHH", "SEQNUMC", "P_UTD431H314_ROUT_S", "ESTIAP", "WT", "STRATUM")

R_FILE <- na.omit(R_FILE) 

#---ASSIGN LABELS---# 

R_FILE$P_UTD431H314_ROUT_S <- factor(R_FILE$P_UTD431H314_ROUT_S, levels=UTD431H314levels,

labels=UTD431H314labels)

R_FILE$ESTIAP <- factor(R_FILE$ESTIAP, levels=ESTIAPlevels,

labels=ESTIAPlabels)

#---SPECIFY A SAMPLING DESIGN AND FORCE WT AS NUMERIC---# 

svydsg <- svydesign(id=~SEQNUMHH, strata=~STRATUM, weights=~(as.numeric(WT)),

data=R_FILE) 

#---U.S. TOTAL ESTIMATES AND STANDARD ERRORS---# 

r_nation <- svymean(~P_UTD431H314_ROUT_S, svydsg)

PERCENT_UTD <- round(r_nation*100,2) #CONVERT INTO PERCENT ESTIMATES(MEAN)

SE_UTD <- round(SE(r_nation)*100,2) #CONVERT INTO PERCENT ESTIMATES(SE)

r_nation_est <- cbind(PERCENT_UTD, SE_UTD)

title <- "PERCENT 4:3:1:3:3:1:4 ESTIMATES AT A NATIONAL LEVEL"

prn(r_nation_est, title)

#---ESTIMATION AREA ESTIMATES AND STANDARD ERRORS---# 

r_est <- svyby(~P_UTD431H314_ROUT_S, ~ESTIAP, svydsg, svymean)

r_est[,-c(1)] <- round(r_est[,-c(1)]*100,2) #CONVERT INTO PERCENT ESTIMATES

r_est <- subset(r_est, select=c(1,3,5))
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#SELECT ESTIMATES FOR UP-TO-DATE CASES

names(r_est) <- c("ESTIMATION AREA", "PERCENT 4:3:1:3:3:1:4 UTD", "STANDARD ERROR UTD")

title <- "PERCENT 4:3:1:3:3:1:4 ESTIMATES BY ESTIMATION AREA"

prn(r_est, title)

###################### 

title <- "R_STATE.R"

###################################################################### 

#THIS PROGRAM WILL PRODUCE STATE ESTIMATES AND STANDARD ERRORS

#FOR P_UTD431H314_ROUT_S USING R.

# 

#NOTE : THE STATE VARIABLE IS BASED ON FIPSTATE CODES ,THERE ARE

#NO STATES WITH FIPS CODES 3,7,14,43,52,57-71,73-78. 

# 

#R NOTES:

#1. R IS CASE SENSITIVE.

#2. A FILE PATH IS SEPERATED BY SLASH(/)

###################################################################### 

library(survey) #TO USE svydesign(), svymean(), and svyby()

library(Hmisc) #TO USE prn()

dd <- "c:/nispuf21" #"path-to-data"

#--- NAME OF R DATASET ---# 

in.file <- paste(dd,"/NISPUF21.RData",sep="")

#---READ R DATASET---# 

load(in.file) 

#---FORMAT---# 

UTD431H314levels=c(0,1)

UTD431H314labels=c("NOT 4:3:1:3:3:1:4 UTD", "4:3:1:3:3:1:4 UTD")

STATElevels=c(1, 2, 4, 5, 6, 8, 9, 10, 11, 12, 13, 15, 16, 17,

18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,

36, 37, 38, 39, 40, 41, 42, 44, 45, 46, 47, 48, 49, 50, 51, 53,

54, 55, 56, 72) 

STATElabels=c(

"ALABAMA",

"ALASKA",

"ARIZONA",

"ARKANSAS",

"CALIFORNIA",

"COLORADO",

"CONNECTICUT",

"DELAWARE",

"DISTRICT OF COLUMBIA",

"FLORIDA",

"GEORGIA",

"HAWAII",

"IDAHO",

"ILLINOIS", 

"INDIANA",

"IOWA",

"KANSAS",

"KENTUCKY",

"LOUISIANA",

"MAINE",

"MARYLAND",

"MASSACHUSETTS",

"MICHIGAN",

"MINNESOTA",

"MISSISSIPPI",

"MISSOURI",

"MONTANA",
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132

"NEBRASKA",

"NEVADA",

"NEW HAMPSHIRE",

"NEW JERSEY",

"NEW MEXICO",

"NEW YORK",

"NORTH CAROLINA",

"NORTH DAKOTA",

"OHIO",

"OKLAHOMA",

"OREGON",

"PENNSYLVANIA",

"RHODE ISLAND",

"SOUTH CAROLINA",

"SOUTH DAKOTA",

"TENNESSEE",

"TEXAS",

"UTAH",

"VERMONT",

"VIRGINIA", 

"WASHINGTON",

"WEST VIRGINIA",

"WISCONSIN",

"WYOMING", 

"PUERTO RICO" 

) 

#---PROVWT_C WILL BE USED AS A WEIGHT (PROVWT_C IS THE SINGLE-FRAME CELLULAR PHONE WEIGHT EXCLUDING 

TERRITORIES; USE PROVWT_C_TERR TO INCLUDE TERRITORIES)---# 

#---STRATUM WILL BE USED AS A STRATUM VARIABLE FOR VARIANCE ESTIMATION ---# 

R_FILE <- subset(NISPUF21, select=c(SEQNUMHH, SEQNUMC, P_UTD431H314_ROUT_S, 

STATE, PROVWT_C, STRATUM))

names(R_FILE) <- c("SEQNUMHH", "SEQNUMC", "P_UTD431H314_ROUT_S", "STATE",

"WT","STRATUM")

R_FILE <- na.omit(R_FILE) 

#---ASSIGN LABELS---# 

R_FILE$P_UTD431H314_ROUT_S <- factor(R_FILE$P_UTD431H314_ROUT_S, levels=UTD431H314levels,

labels=UTD431H314labels)

R_FILE$STATE <- factor(R_FILE$STATE, levels=STATElevels,

labels=STATElabels)

#---SPECIFY A SAMPLING DESIGN AND FORCE WT AS NUMERIC---# 

svydsg <- svydesign(id=~SEQNUMHH, strata=~STRATUM, weights=~(as.numeric(WT)),

data=R_FILE) 

#---STATE ESTIMATES AND STANDARD ERRORS---# 

r_est2 <- svyby(~P_UTD431H314_ROUT_S, ~STATE, svydsg, svymean)

r_est2[,-c(1)] <- round(r_est2[,-c(1)]*100,2) #CONVERT INTO PERCENT ESTIMATES

r_est2 <- subset(r_est2, select=c(1,3,5)) #SELECT ESTIMATES FOR UP-TO-DATE CASES

names(r_est2) <- c("STATE", "PERCENT 4:3:1:3:3:1:4 UTD", "STANDARD ERROR UTD")

prn(r_est2, '4:3:1:3:3:1:4 ESTIMATES BY STATE')

###################### 

title <- "R_PROG_3.R" 

###################################################################### 

#THIS PROGRAM WILL PRODUCE A TABLE OF HAD_CPOX BY STATE FOR ALL RDD

#COMPLETES USING RDDWT_C. THE PROGRAM USES R.

# 

#R NOTES:

#1. R IS CASE SENSITIVE.

#2. A FILE PATH IS SEPERATED BY SLASH(/)

###################################################################### 

library(survey) #TO USE svydesign(), svymean(), and svyby()

library(Hmisc) #TO USE prn()

library(prettyR) #TO USE freq()

dd <- "c:/nispuf21" #"path-to-dataset"
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-Child Public-Use Data FileAPPENDIX D 

133

#--- NAME OF R DATASET ---# 

in.file <- paste(dd,"/NISPUF21.RData",sep="")

#---READ R DATASET---# 

load(in.file) 

#---FORMAT---# 

HAD_CPOXlevels=c(1,2,77,99) 

HAD_CPOXlabels=c("YES", "NO", "DON'T KNOW", "REFUSED")

STATElevels=c(1, 2, 4, 5, 6, 8, 9, 10, 11, 12, 13, 15, 16, 17,

18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,

36, 37, 38, 39, 40, 41, 42, 44, 45, 46, 47, 48, 49, 50, 51, 53,

54, 55, 56, 72) 

STATElabels=c(

"ALABAMA",

"ALASKA",

"ARIZONA",

"ARKANSAS",

"CALIFORNIA",

"COLORADO",

"CONNECTICUT",

"DELAWARE",

"DISTRICT OF COLUMBIA",

"FLORIDA",

"GEORGIA",

"HAWAII",

"IDAHO",

"ILLINOIS", 

"INDIANA",

"IOWA",

"KANSAS",

"KENTUCKY",

"LOUISIANA",

"MAINE",

"MARYLAND",

"MASSACHUSETTS",

"MICHIGAN",

"MINNESOTA",

"MISSISSIPPI",

"MISSOURI",

"MONTANA",

"NEBRASKA",

"NEVADA",

"NEW HAMPSHIRE",

"NEW JERSEY",

"NEW MEXICO",

"NEW YORK",

"NORTH CAROLINA",

"NORTH DAKOTA",

"OHIO",

"OKLAHOMA",

"OREGON",

"PENNSYLVANIA",

"RHODE ISLAND",

"SOUTH CAROLINA",

"SOUTH DAKOTA",

"TENNESSEE",

"TEXAS",

"UTAH",

"VERMONT",

"VIRGINIA", 

"WASHINGTON",

"WEST VIRGINIA",

"WISCONSIN",

"WYOMING", "PUERTO RICO" 
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134

) 

#---RDDWT_C WILL BE USED AS A WEIGHT (RDDWT_C IS THE SINGLE-FRAME CELLULAR PHONE WEIGHT EXCLUDING 

TERRITORIES; USE RDDWT_C_TERR TO INCLUDE TERRITORIES)---# 

#---STRATUM WILL BE USED AS A STRATUM VARIABLE FOR VARIANCE ESTIMATION ---# 

R_FILE <- subset(NISPUF21, select=c(SEQNUMHH, SEQNUMC, STATE,

HAD_CPOX, RDDWT_C, STRATUM))

names(R_FILE) <- c("SEQNUMHH", "SEQNUMC", "STATE", "HAD_CPOX",

"WT", "STRATUM")

#---ASSIGN LABELS---# 

R_FILE$HAD_CPOX <- factor(R_FILE$HAD_CPOX, levels=HAD_CPOXlevels,

labels=HAD_CPOXlabels)

R_FILE$STATE <- factor(R_FILE$STATE, levels=STATElevels,

labels=STATElabels)

R_FILE <- na.omit(R_FILE) 

summary(R_FILE$HAD_CPOX) 

#---SPECIFY A SAMPLING DESIGN AND FORCE WT AS NUMERIC---# 

svydsg <- svydesign(id=~SEQNUMHH, strata=~STRATUM, weights=~(as.numeric(WT)),

data=R_FILE) 

#---U.S. TOTAL ESTIMATES AND STANDARD ERRORS---# 

r_nation <- svymean(~HAD_CPOX, svydsg)

PERCENT_UTD <- round(r_nation*100,2) #CONVERT INTO PERCENT ESTIMATES(MEAN)

SE_UTD <- round(SE(r_nation)*100,2) #CONVERT INTO PERCENT ESTIMATES(SE)

r_nation_est3 <- cbind(PERCENT_UTD, SE_UTD)

prn(r_nation_est3, "PERCENT HAD_CPOX = YES ESTIMATES AT A NATIONAL

LEVEL\n")

#---HAD_CPOX = YES ESTIMATES BY STATE---# 

r_est3 <- svyby(~HAD_CPOX, ~STATE, svydsg, svymean)

r_est3[,-c(1)] <- round(r_est3[,-c(1)]*100,2) #CONVERT INTO PERCENT ESTIMATES

r_est3 <- subset(r_est3, select=c(1,2,6)) #SELECT ESTIMATES FOR HAD_CPOX=YES

names(r_est3) <- c("STATE", "PERCENT HAD_CPOX=YES", "STANDARD ERROR

HAD_CPOX=Y")

prn(r_est3, 'PERCENT HAD_CPOX ESTIMATES BY STATE')

###################### 

title <- "PROG_4.R" 

######################################################################### 

#TABLE OF P_UTD431H314_ROUT_S BY INCPOV1 BY RACE_K. SAVE % UTD

#ESTIMATES (NOT S.E.'S) FOR USE IN THE PROGRAM GRAPH_4.

# 

#THIS PROGRAM WILL PRODUCE ESTIMATES USING R.

# 

#R NOTES:

#1. R IS CASE SENSITIVE.

#2. A FILE PATH IS SEPERATED BY SLASH(/)

######################################################################### 

library(survey) #TO USE svydesign(), svymean(), and svyby()

library(Hmisc) #TO USE prn()

dd <- "c:/nispuf21" #"path-to-dataset"

out <-"c:/nispuf21" #"path-to-output" 

#--- NAME OF R DATASET ---# 

in.file <- paste(dd,"/NISPUF21.RData",sep="")

#---READ R DATASET---# 

load(in.file) 

#---FORMAT---# 
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135

UTD431H314levels=c(0,1)

UTD431H314labels=c("NOT 4:3:1:3:3:1:4 UTD", "4:3:1:3:3:1:4 UTD")

RACE_PUFlevels=c(1,2,3) 

RACE_PUFlabels=c("WHITE ONLY", "BLACK ONLY", "OTHER + MULTIPLE RACE")

INCPOVlevels=c(1,2,3,4) 

INCPOVlabels=c("ABOVE POVERTY, > $75K", "ABOVE POVERTY, <= $75K", "BELOW POVERTY", "UNKNOWN")

#---PROVWT_C WILL BE USED AS A WEIGHT (PROVWT_C IS THE SINGLE-FRAME CELLULAR PHONE WEIGHT EXCLUDING 

TERRITORIES; USE PROVWT_C_TERR TO INCLUDE TERRITORIES)---# 

#---STRATUM WILL BE USED AS A STRATUM VARIABLE FOR VARIANCE ESTIMATION ---# 

R_FILE <- subset(NISPUF21, select=c(SEQNUMHH, SEQNUMC, P_UTD431H314_ROUT_S, RACE_K, INCPOV1, PROVWT_C, STRATUM))

names(R_FILE) <- c("SEQNUMHH", "SEQNUMC", "P_UTD431H314_ROUT_S", "RACE_K", "INCPOV1", "WT", "STRATUM")

#---ASSIGN LABELS---# 

R_FILE$P_UTD431H314_ROUT_S <- factor(R_FILE$P_UTD431H314_ROUT_S, levels=UTD431H314levels, labels=UTD431H314labels, 

exclude=NULL)

R_FILE$RACE_K <- factor(R_FILE$RACE_K, levels=RACE_PUFlevels, labels=RACE_PUFlabels, exclude=NULL)

R_FILE$INCPOV1 <- factor(R_FILE$INCPOV1, levels=INCPOVlevels,labels=INCPOVlabels, exclude=NULL)

#---UNWEIGHTED FREQUENCIES---# 

unwt_freq <- function(UNWT.VAR){#FUNCTION TO PRINT UNWEIGHTED FREQUENCIES

unwt.tab <- wtd.table(UNWT.VAR, weights= NULL, type='table')

unwtd.freq <- data.frame(cbind( 

unwt.tab, round(unwt.tab/sum(unwt.tab)*100,2),

cumsum(unwt.tab), cumsum(round(unwt.tab/sum(unwt.tab)*100,2))))

names(unwtd.freq) <- c("Frequency", "Percent", "Cumulative Frequency", "Cumulative Percent")

unwtd.title <- paste('Table 4A. Q1/2021 - Q4/2021', 'UNWEIGHTED FREQUENCIES', label(UNWT.VAR), sep="\n")

label(unwtd.freq) <- unwtd.title 

print(unwtd.freq) 

} 

unwt_freq(R_FILE$P_UTD431H314_ROUT_S) 

unwt_freq(R_FILE$INCPOV1) 

unwt_freq(R_FILE$RACE_K) 

R_FILE <- na.omit(R_FILE) 

#---SPECIFY A SAMPLING DESIGN AND FORCE WT AS NUMERIC---# 

svydsg <- svydesign(id=~SEQNUMHH, strata=~STRATUM, weights=~(as.numeric(WT)),

data=R_FILE) 

#---PERCENT 4:3:1:3:3:1:4 UP-TO-DATE AND ESTIMATED STANDARD ERRORS---# 

r_est4 <- svyby(~P_UTD431H314_ROUT_S, ~RACE_K+INCPOV1, svydsg, svymean)

r_est4[,-c(1,2)] <- round(r_est4[,-c(1,2)]*100,2) #CONVERT INTO PERCENT ESTIMATES

r_est4 <- subset(r_est4, select=c(1,2,4,6)) #SELECT ESTIMATES FOR UP-TODATE CASES

names(r_est4) <- c("RACE", "INCOME", "PERCENT_UTD", "STANDARD_ERROR_UTD")

title <- "Table 4B. Q1/2021 - Q4/2021, Percent 4:3:1:3:3:1:4 UTD and Estimated Standard Errors"

prn(r_est4, title)

#---SAVE PERCENT UP-TO-DATE ESTIMATES FOR USE IN THE PROGRAM GRAPH_4---# 

r_est4 <- subset(r_est4, select=c(RACE, INCOME, PERCENT_UTD))

save(r_est4, file=paste(out, "/r_est4", sep=""))

###################### 

title <- "GRAPH_4.R" 

######################################################################### 

#THIS PROGRAM BUILDS OFF OF THE PROGRAM PROG_4. IT PRODUCES A CHART OF

#P_UTD431H314_ROUT_S BY INCPOV1 BY RACE_K. IT CREATES A BAR CHART IN R GRAPH FOR

#THE 4X3 = 12 CELLS.

#R NOTES:

#1. R IS CASE SENSITIVE.

#2. A FILE PATH IS SEPERATED BY SLASH(/)

######################################################################### 

library(survey) #TO USE svydesign(), svymean(), and svyby()

library(Hmisc) #TO USE prn()

dd <- "c:/nispuf21" #---SPECIFY PATH TO R DATASET THAT WAS THE OUTPUT OF R_PROG_4---# 

out <- "c:/nispuf21" #---SPECIFY THE PATH FOR WHERE YOU WANT THE CHART OUTPUT TO GO---# 
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136

#---NAME OF R DATASET OUTPUT FROM R_PROG_4---# 

in.file <- paste(dd,"/r_est4",sep="")

#---READ R DATASET---# 

load(in.file) 

#---BARCHART---# 

#NOTE:R DOES NOT SUPPORT CREATING A HTML FILE CONTAINING A BARCHART#

#CREATE A DATA MATRIX FOR DRAWING A BARCHART#

utd431H314 <- matrix(r_est4$PERCENT_UTD, nrow=3, ncol=4, byrow=F, dimnames=list(levels(r_est4$RACE), levels(r_est4$INCOME)))

#CREATE GRAPH_4_R # 

png(file=paste(out,"/GRAPH_4_R.png",sep=""), width=1000, height=700)

barplot(utd431H314, beside=TRUE, space=c(0.2,1),

 col = c("wheat", "lightpink2", "forestgreen"),

 axis.lty = 1,

 sub="(Graph 4 using 'R')", cex.sub=1, ylim=c(0,120),

 xlab="Poverty Status",

 ylab="4:3:1:3:3:1:4 Up-To-Date (%)", cex=1.1, cex.names=1, cex.lab=1.5, border=NA)

legend("top", rownames(utd431H314), col=c("wheat", "lightpink2",

 "forestgreen"), title="Race of Child", pch=10, cex=1.5)

title1 <- "Percentage of Children Up-to-Date with Vaccine Series 4:3:1:3:3:1:4 \n" 

title2 <- "by Race and Poverty Status, National Immunization Survey - Child, 2021\n" 

mtext(paste(title1,title2), cex=1.5)

dev.off() 
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137

Appendix E: Alphabetical Listing of Variables that are in the 2004-2021 Public-Use Data 

Files

Table E.1 Alphabetical Listing of Variables that are in the 2004-2021 Public-Use Data Files*

Year of Data Collection

Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

AGECPOXR 

AGE IN MONTHS AT 

CHICKEN POX DISEASE 

(RECODE)

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Replaced IAGECPXR starting 2005. 

This version is not imputed.

AGEGRP 

AGE CATEGORY OF 

CHILD (19-23, 24-29, 30-35 

MO) (RECODE)

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

ALL4SHOT HH REPORT OF 4:3:1:3 UPTO-DATE Y Y 

Dropped starting in 2006 because no 

longer possible to derive due to 

questionnaire change. 

BF_ENDR 

DURATION OF 

BREASTFEEDING IN DAYS 

(TOPCODE) 

Y Y 

Dropped starting in 2006 because of 

question wording change. Replaced by 

BF_ENDR06. 

BF_ENDR06 

DURATION OF 

BREASTFEEDING IN DAYS 

(RECODE)

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Replaced BF_ENDR starting 2006.

BF_EXCLR

DURATION OF 

EXCLUSIVE 

BREASTFEEDING IN DAYS 

(TOPCODE) 

Y Y 

Dropped starting in 2006 because of 

question wording change. Replaced by 

BF_EXCLR06.

BF_EXCLR06

DURATION OF 

EXCLUSIVE 

BREAST/FORMULA 

FEEDING IN DAYS 

(RECODE)

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Replaced BF_EXCLR starting 2006.

BF_FORMR06 

AGE IN DAYS WHEN 

CHILD FIRST FED 

FORMULA (TOPCODE)

Y Y 

Question CBF_03_X added starting 

2006. Replaced by BF_FORMR06 

starting 2008.

BF_FORMR08 

AGE IN DAYS WHEN 

CHILD FIRST FED 

FORMULA (RECODE)

Y Y Y Y Y Y Y Y Y Y Y Y 

Replaced BF_FORMR06 to add a 

"never fed formula" code. Replaced by 

BF_FORMR20 starting in 2020.

BF_FORMR20

AGE IN DAYS WHEN 

CHILD FIRST FED 

FORMULA (RECODE)

Y Y Replaced BF_FORMR08 due to a 

change in the top-coding cutoff. 

BFENDFL 

DURATION OF BREAST 

FEEDING EXCEEDS CHILD 

AGE IN DAYS, WITH 

BUFFER 

Y Y 

Dropped starting in 2006 because of 

question wording change. Replaced by 

BFENDFL06. 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

BFENDFL06 

DURATION OF BREAST 

FEEDING EXCEEDS CHILD 

AGE IN DAYS, WITH 

BUFFER 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Replaced BFENDFL starting 2006.

BFEXCLFL

DURATION OF 

EXCLUSIVE BREAST 

FEEDING EXCEEDS 

TOTAL BREASTFEEDING, 

WITH BUFFER

Y Y 

Dropped starting in 2006 because 

question wording change does not 

allow it to be derived.

BFFORMFL06 

AGE IN DAYS WHEN 

CHILD FIRST FED 

FORMULA EXCEEDS 

CHILD AGE IN DAYS, 

WITH BUFFER

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Question CBF_03_X added starting 

2006.

C_431

HH REPORT OF 4:3:1 UPTO-DATE BY SHOT CARD 

USE 

Y Y 

Dropped starting in 2006 because no 

longer possible to derive due to 

questionnaire change. 

C_4313

HH REPORT OF 4:3:1:3 UPTO-DATE BY SHOT CARD 

USE 

Y Y 

Dropped starting in 2006 because no 

longer possible to derive due to 

questionnaire change. 

C_DTP

HH REPORT OF 4+ DTCONTAINING UP-TODATE BY SHOT CARD USE

Y Y 

Dropped starting in 2006 because no 

longer possible to derive due to 

questionnaire change. 

C_HEP

HH REPORT OF 3+ 

HEPATITIS BCONTAINING UP-TODATE BY SHOT CARD USE

Y Y 

Dropped starting in 2006 because no 

longer possible to derive due to 

questionnaire change. 

C_HIB

HH REPORT OF 3+ HIBCONTAINING UP-TODATE BY SHOT CARD USE

Y Y 

Dropped starting in 2006 because no 

longer possible to derive due to 

questionnaire change. 

C_MMR

HH REPORT OF 1+ 

MEASLES-CONTAINING 

UP-TO-DATE BY SHOT 

CARD USE

Y Y 

Dropped starting in 2006 because no 

longer possible to derive due to 

questionnaire change. 

C_POL 

HH REPORT OF 3+ POLIOCONTAINING UP-TODATE BY SHOT CARD USE

Y Y 

Dropped starting in 2006 because no 

longer possible to derive due to 

questionnaire change. 

C_VRC

HH REPORT OF 1+ 

VARICELLA-CONTAINING 

UP-TO-DATE BY SHOT 

CARD USE

Y Y 

Dropped starting in 2006 because no 

longer possible to derive due to 

questionnaire change. 

C1R NUMBER OF PEOPLE IN 

HOUSEHOLD (RECODE) Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

C5R

RELATIONSHIP OF 

RESPONDENT TO CHILD 

(RECODE)

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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139

Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

CBF_01

WAS CHILD EVER 

BREASTFED OR FED 

BREAST MILK?

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

CEN_REG

CENSUS REGION BASED 

ON TRUE STATE OF 

RESIDENCE

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

CHILDNM

NUMBER OF CHILDREN 

LESS THAN 18 YEARS IN 

HH (RECODE)

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

CWIC_01 CHILD EVER RECEIVED 

WIC BENEFITS? Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

CWIC_02

CHILD CURRENTLY 

RECEIVING WIC 

BENEFITS?

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

D6R 

NUMBER OF 

VACCINATION 

PROVIDERS IDENTIFIED 

BY RESPONDENT 

(RECODE)

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

D7 

CONSENT TO OBTAIN 

CHILD'S IMMUNIZATION 

RECORDS FROM 

PROVIDERS 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DDTP1 

AGE IN DAYS OF PROVREPTD DT-CONTAINING 

SHOT #1

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DDTP2 

AGE IN DAYS OF PROVREPTD DT-CONTAINING 

SHOT #2

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DDTP3 

AGE IN DAYS OF PROVREPTD DT-CONTAINING 

SHOT #3

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DDTP4 

AGE IN DAYS OF PROVREPTD DT-CONTAINING 

SHOT #4

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DDTP5 

AGE IN DAYS OF PROVREPTD DT-CONTAINING 

SHOT #5

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DDTP6 

AGE IN DAYS OF PROVREPTD DT-CONTAINING 

SHOT #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DDTP7 

AGE IN DAYS OF PROVREPTD DT-CONTAINING 

SHOT #7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

DDTP8 

AGE IN DAYS OF PROVREPTD DT-CONTAINING 

SHOT #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DDTP9 

AGE IN DAYS OF PROVREPTD DT-CONTAINING 

SHOT #9

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DFLU1 

AGE IN DAYS OF PROVREPTD SEASONAL FLUCONTAINING 

VACCINATION #1

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DFLU2 

AGE IN DAYS OF PROVREPTD SEASONAL FLUCONTAINING 

VACCINATION #2

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DFLU3 

AGE IN DAYS OF PROVREPTD SEASONAL FLUCONTAINING 

VACCINATION #3

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DFLU4 

AGE IN DAYS OF PROVREPTD SEASONAL FLUCONTAINING 

VACCINATION #4

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DFLU5 

AGE IN DAYS OF PROVREPTD SEASONAL FLUCONTAINING 

VACCINATION #5

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DFLU6 

AGE IN DAYS OF PROVREPTD SEASONAL FLUCONTAINING 

VACCINATION #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DFLU7 

AGE IN DAYS OF PROVREPTD SEASONAL FLUCONTAINING 

VACCINATION #7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DFLU8 

AGE IN DAYS OF PROVREPTD SEASONAL FLUCONTAINING 

VACCINATION #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DFLU9 

AGE IN DAYS OF PROVREPTD SEASONAL FLUCONTAINING 

VACCINATION #9

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DH1N1 

AGE IN DAYS OF PROVREPTD MONOVALENT 

2009 H1N1 INFLUENZA 

VACCINATION #1

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.
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141

Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

DH1N2 

AGE IN DAYS OF PROVREPTD MONOVALENT 

2009 H1N1 INFLUENZA 

VACCINATION #2

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

DH1N3 

AGE IN DAYS OF PROVREPTD MONOVALENT 

2009 H1N1 INFLUENZA 

VACCINATION #3

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

DH1N4 

AGE IN DAYS OF PROVREPTD MONOVALENT 

2009 H1N1 INFLUENZA 

VACCINATION #4

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

DH1N5 

AGE IN DAYS OF PROVREPTD MONOVALENT 

2009 H1N1 INFLUENZA 

VACCINATION #5

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

DH1N6 

AGE IN DAYS OF PROVREPTD MONOVALENT 

2009 H1N1 INFLUENZA 

VACCINATION #6

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

DH1N7 

AGE IN DAYS OF PROVREPTD MONOVALENT 

2009 H1N1 INFLUENZA 

VACCINATION #7

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

DH1N8 

AGE IN DAYS OF PROVREPTD MONOVALENT 

2009 H1N1 INFLUENZA 

VACCINATION #8

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

DH1N9 

AGE IN DAYS OF PROVREPTD MONOVALENT 

2009 H1N1 INFLUENZA 

VACCINATION #9

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

DHEPA1 

AGE IN DAYS OF PROVREPTD HEPATITIS ACONTAINING SHOT #1

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHEPA2 

AGE IN DAYS OF PROVREPTD HEPATITIS ACONTAINING SHOT #2

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

DHEPA3 

AGE IN DAYS OF PROVREPTD HEPATITIS ACONTAINING SHOT #3

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHEPA4 

AGE IN DAYS OF PROVREPTD HEPATITIS ACONTAINING SHOT #4

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHEPA5 

AGE IN DAYS OF PROVREPTD HEPATITIS ACONTAINING SHOT #5

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHEPA6 

AGE IN DAYS OF PROVREPTD HEPATITIS ACONTAINING SHOT #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHEPA7 

AGE IN DAYS OF PROVREPTD HEPATITIS ACONTAINING SHOT #7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHEPA8 

AGE IN DAYS OF PROVREPTD HEPATITIS ACONTAINING SHOT #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHEPA9 

AGE IN DAYS OF PROVREPTD HEPATITIS ACONTAINING SHOT #9

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DHEPB1 

AGE IN DAYS OF PROVREPTD HEPATITIS BCONTAINING SHOT #1

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHEPB2 

AGE IN DAYS OF PROVREPTD HEPATITIS BCONTAINING SHOT #2

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHEPB3 

AGE IN DAYS OF PROVREPTD HEPATITIS BCONTAINING SHOT #3

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHEPB4 

AGE IN DAYS OF PROVREPTD HEPATITIS BCONTAINING SHOT #4

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHEPB5 

AGE IN DAYS OF PROVREPTD HEPATITIS BCONTAINING SHOT #5

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHEPB6 

AGE IN DAYS OF PROVREPTD HEPATITIS BCONTAINING SHOT #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHEPB7 

AGE IN DAYS OF PROVREPTD HEPATITIS BCONTAINING SHOT #7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHEPB8 

AGE IN DAYS OF PROVREPTD HEPATITIS BCONTAINING SHOT #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

DHEPB9 

AGE IN DAYS OF PROVREPTD HEPATITIS BCONTAINING SHOT #9

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DHIB1 

AGE IN DAYS OF PROVREPTD HIB-CONTAINING 

SHOT #1

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHIB2 

AGE IN DAYS OF PROVREPTD HIB-CONTAINING 

SHOT #2

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHIB3 

AGE IN DAYS OF PROVREPTD HIB-CONTAINING 

SHOT #3

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHIB4 

AGE IN DAYS OF PROVREPTD HIB-CONTAINING 

SHOT #4

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHIB5 

AGE IN DAYS OF PROVREPTD HIB-CONTAINING 

SHOT #5

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHIB6 

AGE IN DAYS OF PROVREPTD HIB-CONTAINING 

SHOT #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHIB7 

AGE IN DAYS OF PROVREPTD HIB-CONTAINING 

SHOT #7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHIB8 

AGE IN DAYS OF PROVREPTD HIB-CONTAINING 

SHOT #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DHIB9 

AGE IN DAYS OF PROVREPTD HIB-CONTAINING 

SHOT #9

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DISPCODE 

NIS PROVIDER RECORDCHECK DISPOSITION 

CODE 

Y Y Y Y Y Y Y Y 

Dropped starting in 2012 because no 

longer possible to derive due to 

questionnaire change

DMMR1

AGE IN DAYS OF PROVREPTD MEASLESCONTAINING SHOT #1

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DMMR2

AGE IN DAYS OF PROVREPTD MEASLESCONTAINING SHOT #2

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DMMR3

AGE IN DAYS OF PROVREPTD MEASLESCONTAINING SHOT #3

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DMMR4

AGE IN DAYS OF PROVREPTD MEASLESCONTAINING SHOT #4

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

DMMR5

AGE IN DAYS OF PROVREPTD MEASLESCONTAINING SHOT #5

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DMMR6

AGE IN DAYS OF PROVREPTD MEASLESCONTAINING SHOT #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DMMR7

AGE IN DAYS OF PROVREPTD MEASLESCONTAINING SHOT #7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DMMR8

AGE IN DAYS OF PROVREPTD MEASLESCONTAINING SHOT #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DMMR9

AGE IN DAYS OF PROVREPTD MEASLESCONTAINING SHOT #9

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DMP1 

AGE IN DAYS OF PROVREPTD MUMPS-ONLY 

SHOT #1

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DMP2 

AGE IN DAYS OF PROVREPTD MUMPS-ONLY 

SHOT #2

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DMP3 

AGE IN DAYS OF PROVREPTD MUMPS-ONLY 

SHOT #3

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DMP4 

AGE IN DAYS OF PROVREPTD MUMPS-ONLY 

SHOT #4

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DMP5 

AGE IN DAYS OF PROVREPTD MUMPS-ONLY 

SHOT #5

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DMP6 

AGE IN DAYS OF PROVREPTD MUMPS-ONLY 

SHOT #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DMP7 

AGE IN DAYS OF PROVREPTD MUMPS-ONLY 

SHOT #7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DMP8 

AGE IN DAYS OF PROVREPTD MUMPS-ONLY 

SHOT #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DMP9 

AGE IN DAYS OF PROVREPTD MUMPS-ONLY 

SHOT #9

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DMPRB1 

AGE IN DAYS OF PROVREPTD 

(MUMPS/RUBELLA)-ONLY 

SHOT #1

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

DMPRB2 

AGE IN DAYS OF PROVREPTD 

(MUMPS/RUBELLA)-ONLY 

SHOT #2

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DMPRB3 

AGE IN DAYS OF PROVREPTD 

(MUMPS/RUBELLA)-ONLY 

SHOT #3

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DMPRB4 

AGE IN DAYS OF PROVREPTD 

(MUMPS/RUBELLA)-ONLY 

SHOT #4

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DMPRB5 

AGE IN DAYS OF PROVREPTD 

(MUMPS/RUBELLA)-ONLY 

SHOT #5

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DMPRB6 

AGE IN DAYS OF PROVREPTD 

(MUMPS/RUBELLA)-ONLY 

SHOT #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DMPRB7 

AGE IN DAYS OF PROVREPTD 

(MUMPS/RUBELLA)-ONLY 

SHOT #7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DMPRB8 

AGE IN DAYS OF PROVREPTD 

(MUMPS/RUBELLA)-ONLY 

SHOT #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DMPRB9 

AGE IN DAYS OF PROVREPTD 

(MUMPS/RUBELLA)-ONLY 

SHOT #9

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DPCV1 

AGE IN DAYS OF PROVREPTD PNEUMOCOCCALCONTAINING SHOT #1

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DPCV2 

AGE IN DAYS OF PROVREPTD PNEUMOCOCCALCONTAINING SHOT #2

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DPCV3 

AGE IN DAYS OF PROVREPTD PNEUMOCOCCALCONTAINING SHOT #3

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DPCV4 

AGE IN DAYS OF PROVREPTD PNEUMOCOCCALCONTAINING SHOT #4

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DPCV5 

AGE IN DAYS OF PROVREPTD PNEUMOCOCCALCONTAINING SHOT #5

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

DPCV6 

AGE IN DAYS OF PROVREPTD PNEUMOCOCCALCONTAINING SHOT #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DPCV7 

AGE IN DAYS OF PROVREPTD PNEUMOCOCCALCONTAINING SHOT #7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DPCV8 

AGE IN DAYS OF PROVREPTD PNEUMOCOCCALCONTAINING SHOT #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DPCV9 

AGE IN DAYS OF PROVREPTD PNEUMOCOCCALCONTAINING SHOT #9

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DPOLIO1 

AGE IN DAYS OF PROVREPTD POLIOCONTAINING SHOT #1

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DPOLIO2 

AGE IN DAYS OF PROVREPTD POLIOCONTAINING SHOT #2

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DPOLIO3 

AGE IN DAYS OF PROVREPTD POLIOCONTAINING SHOT #3

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DPOLIO4 

AGE IN DAYS OF PROVREPTD POLIOCONTAINING SHOT #4

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DPOLIO5 

AGE IN DAYS OF PROVREPTD POLIOCONTAINING SHOT #5

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DPOLIO6 

AGE IN DAYS OF PROVREPTD POLIOCONTAINING SHOT #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DPOLIO7 

AGE IN DAYS OF PROVREPTD POLIOCONTAINING SHOT #7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DPOLIO8 

AGE IN DAYS OF PROVREPTD POLIOCONTAINING SHOT #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DPOLIO9 

AGE IN DAYS OF PROVREPTD POLIOCONTAINING SHOT #9

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DRB1

AGE IN DAYS OF PROVREPTD RUBELLA-ONLY 

SHOT #1

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DRB2

AGE IN DAYS OF PROVREPTD RUBELLA-ONLY 

SHOT #2

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

DRB3

AGE IN DAYS OF PROVREPTD RUBELLA-ONLY 

SHOT #3

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DRB4

AGE IN DAYS OF PROVREPTD RUBELLA-ONLY 

SHOT #4

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DRB5

AGE IN DAYS OF PROVREPTD RUBELLA-ONLY 

SHOT #5

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DRB6

AGE IN DAYS OF PROVREPTD RUBELLA-ONLY 

SHOT #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DRB7

AGE IN DAYS OF PROVREPTD RUBELLA-ONLY 

SHOT #7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DRB8

AGE IN DAYS OF PROVREPTD RUBELLA-ONLY 

SHOT #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DRB9

AGE IN DAYS OF PROVREPTD RUBELLA-ONLY 

SHOT #9

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DROT1 

AGE IN DAYS OF PROVREPTD ROTAVIRUSCONTAINING SHOT #1

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DROT2 

AGE IN DAYS OF PROVREPTD ROTAVIRUSCONTAINING SHOT #2

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DROT3 

AGE IN DAYS OF PROVREPTD ROTAVIRUSCONTAINING SHOT #3

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DROT4 

AGE IN DAYS OF PROVREPTD ROTAVIRUSCONTAINING SHOT #4

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DROT5 

AGE IN DAYS OF PROVREPTD ROTAVIRUSCONTAINING SHOT #5

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DROT6 

AGE IN DAYS OF PROVREPTD ROTAVIRUSCONTAINING SHOT #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DROT7 

AGE IN DAYS OF PROVREPTD ROTAVIRUSCONTAINING SHOT #7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DROT8 

AGE IN DAYS OF PROVREPTD ROTAVIRUSCONTAINING SHOT #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

DROT9 

AGE IN DAYS OF PROVREPTD ROTAVIRUSCONTAINING SHOT #9

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DTP_SOUR SHOT CARD USED FOR 

DTP REPORTING Y 

Dropped starting in 2005 because this 

variable is redundant with variable 

SHOTCARD. 

DTP1_AGE 

AGE IN MONTHS OF 

PROV-REPTD DTCONTAINING SHOT #1Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DTP2_AGE 

AGE IN MONTHS OF 

PROV-REPTD DTCONTAINING SHOT #2Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DTP3_AGE 

AGE IN MONTHS OF 

PROV-REPTD DTCONTAINING SHOT #3Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DTP4_AGE 

AGE IN MONTHS OF 

PROV-REPTD DTCONTAINING SHOT #4Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DTP5_AGE 

AGE IN MONTHS OF 

PROV-REPTD DTCONTAINING SHOT #5Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DTP6_AGE 

AGE IN MONTHS OF 

PROV-REPTD DTCONTAINING SHOT #6Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DTP7_AGE 

AGE IN MONTHS OF 

PROV-REPTD DTCONTAINING SHOT #7Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DTP8_AGE 

AGE IN MONTHS OF 

PROV-REPTD DTCONTAINING SHOT #8Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DTP9_AGE 

AGE IN MONTHS OF 

PROV-REPTD DTCONTAINING SHOT #9Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DVRC1 

AGE IN DAYS OF PROVREPTD VARICELLACONTAINING SHOT #1

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DVRC2 

AGE IN DAYS OF PROVREPTD VARICELLACONTAINING SHOT #2

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DVRC3 

AGE IN DAYS OF PROVREPTD VARICELLACONTAINING SHOT #3

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

DVRC4 

AGE IN DAYS OF PROVREPTD VARICELLACONTAINING SHOT #4

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

DVRC5 

AGE IN DAYS OF PROVREPTD VARICELLACONTAINING SHOT #5

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DVRC6 

AGE IN DAYS OF PROVREPTD VARICELLACONTAINING SHOT #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DVRC7 

AGE IN DAYS OF PROVREPTD VARICELLACONTAINING SHOT #7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DVRC8 

AGE IN DAYS OF PROVREPTD VARICELLACONTAINING SHOT #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

DVRC9 

AGE IN DAYS OF PROVREPTD VARICELLACONTAINING SHOT #9

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

EDUC1 

EDUCATION OF MOTHER 

CATEGORIES: IMPUTED

(RECODE)

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

ENTRY2

CHILD LIVES IN STATE 

WITH HEPATITIS B STATE 

ENTRY LAW FOR DAY 

CARE/HEAD START (2001-

2002 SCHOOL YEAR)

Y Dropped starting in 2005.

EST_GRANT 

AREA OF RESIDENCE 

ACCORDING TO THE 56 

ORIGINAL CORE 

GRANTEE AREAS

Y Y Y Y Y Y Y Y Y Y Added in 2012 to facilitate production 

of estimates for the 56 core areas.

ESTIAP ESTIMATION IAP AREA 

OF RESIDENCE Y 

Replaced ITRUEIAP in 2005 because 

estimation areas were modified.

Replaced by ESTIAP06 in 2006.

ESTIAP06 ESTIMATION IAP AREA 

OF RESIDENCE Y 

Replaced ESTIAP in 2006 because 

estimation areas were modified.

Replaced by ESTIAP07 in 2007.

ESTIAP07 ESTIMATION AREA OF 

RESIDENCE Y 

Replaced ESTIAP06 in 2007 because 

estimation areas were modified.

Replaced by ESTIAP08 in 2008.

ESTIAP08 ESTIMATION AREA OF 

RESIDENCE Y 

Replaced ESTIAP07 in 2008 because 

estimation areas were modified.

Replaced by ESTIAP09 in 2009.

ESTIAP09 ESTIMATION AREA OF 

RESIDENCE Y 

Replaced ESTIAP08 in 2009 because 

estimation areas were modified.

Replaced by ESTIAP10 in 2010.

ESTIAP10 ESTIMATION AREA OF 

RESIDENCE Y 

Replaced ESTIAP09 in 2010 because 

estimation areas were modified.

Replaced by ESTIAP11 in 2011.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

ESTIAP11 ESTIMATION AREA OF 

RESIDENCE Y 

Replaced ESTIAP10 in 2011 because 

estimation areas were modified.

Replaced by ESTIAP12 in 2012.

ESTIAP12 ESTIMATION AREA OF 

RESIDENCE Y 

Replaced ESTIAP11 in 2012 because 

estimation areas were modified.

Replaced by ESTIAP13 in 2013.

ESTIAP13 ESTIMATION AREA OF 

RESIDENCE Y 

Replaced ESTIAP12 in 2013 because 

estimation areas were modified.

Replaced by ESTIAP14 in 2014.

ESTIAP14 ESTIMATION AREA OF 

RESIDENCE Y 

Replaced ESTIAP13 in 2014 because 

estimation areas were modified.

Replaced by ESTIAP15 in 2015.

ESTIAP15 ESTIMATION AREA OF 

RESIDENCE Y 

Replaced ESTIAP14 in 2015 because 

estimation areas were modified. 

Replaced by ESTIAP16 in 2016.

ESTIAP16 ESTIMATION AREA OF 

RESIDENCE Y 

Replaced ESTIAP15 in 2016 because 

estimation areas were modified. 

Replaced by ESTIAP17 in 2017.

ESTIAP17 ESTIMATION AREA OF 

RESIDENCE Y 

Replaced ESTIAP16 in 2017 because 

estimation areas were modified. 

Replaced by ESTIAP18 in 2018.

ESTIAP18 ESTIMATION AREA OF 

RESIDENCE Y 

Replaced ESTIAP17 in 2018 because 

estimation areas were modified. 

Replaced by ESTIAP19 in 2019. 

ESTIAP19 ESTIMATION AREA OF 

RESIDENCE Y 

Replaced ESTIAP18 in 2019 because 

estimation areas were modified. 

Replaced by ESTIAP20 in 2020.

ESTIAP20 ESTIMATION AREA OF 

RESIDENCE Y Replaced ESTIAP19 in 2020 because estimation areas were modified.

ESTIAP21 ESTIMATION AREA OF 

RESIDENCE Y Replaced ESTIAP20 in 2021 because estimation areas were modified.

FLU1_AGE 

AGE IN MONTHS OF 

PROV-REPTD SEASONAL 

FLU-CONTAINING 

VACCINATION #1

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

FLU2_AGE 

AGE IN MONTHS OF 

PROV-REPTD SEASONAL 

FLU-CONTAINING 

VACCINATION #2

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

FLU3_AGE 

AGE IN MONTHS OF 

PROV-REPTD SEASONAL 

FLU-CONTAINING 

VACCINATION #3

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

FLU4_AGE 

AGE IN MONTHS OF 

PROV-REPTD SEASONAL 

FLU-CONTAINING 

VACCINATION #4

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

FLU5_AGE 

AGE IN MONTHS OF 

PROV-REPTD SEASONAL 

FLU-CONTAINING 

VACCINATION #5

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

FLU6_AGE 

AGE IN MONTHS OF 

PROV-REPTD SEASONAL 

FLU-CONTAINING 

VACCINATION #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

FLU7_AGE 

AGE IN MONTHS OF 

PROV-REPTD SEASONAL 

FLU-CONTAINING 

VACCINATION #7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

FLU8_AGE 

AGE IN MONTHS OF 

PROV-REPTD SEASONAL 

FLU-CONTAINING 

VACCINATION #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

FLU9_AGE 

AGE IN MONTHS OF 

PROV-REPTD SEASONAL 

FLU-CONTAINING 

VACCINATION #9

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

FRSTBRN FIRST BORN STATUS OF 

CHILD: IMPUTED Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

FUL2_MMR HOUSEHOLD REPORT OF 

1+ MMR AT ANY AGE Y Replaced by FULL_MMR starting in 2005.

FULL_CPO 

HH REPORT OF 1+ 

VARICELLA-CONTAINING 

SHOT AT ANY AGE

Y Y 

Starting 2005, a code of 88 added for 

children with unknown UTD status. 

Dropped starting in 2006 because no 

longer possible to derive due to

questionnaire change. 

FULL_DTP HH REPORT OF 4+ DTCONTAINING SHOT Y Y 

Starting 2005, a code of 88 added for 

children with unknown UTD status. 

Dropped starting in 2006 because no 

longer possible to derive due 

questionnaire change. 

FULL_HEP

HH REPORT OF 3+ 

HEPATITIS BCONTAINING SHOTSY Y 

Starting 2005, a code of 88 added for 

children with unknown UTD status. 

Dropped starting in 2006 because no 

longer possible to derive due to 

questionnaire change. 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

FULL_HIB HH REPORT OF 3+ HIBCONTAINING SHOTS Y Y 

Starting 2005, a code of 88 added for 

children with unknown UTD status. 

Dropped starting in 2006 because no 

longer possible to derive due to 

questionnaire change. 

FULL_MMR

HH REPORT OF 1+ 

MEASLES-CONTAINING 

SHOT AT ANY AGE

Y 

Replaced FUL2_MMR starting in 

2005. A code of 88 added for children 

with unknown UTD status. Dropped 

starting in 2006 because no longer 

possible to derive due to questionnaire 

change. 

FULL_POL HH REPORT OF 3+ POLIOCONTAINING SHOTS Y Y 

Starting 2005, a code of 88 added for 

children with unknown UTD status. 

Dropped starting in 2006 because no 

longer possible to derive due to 

questionnaire change. 

H1N1_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATION #1

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

H1N2_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATION #2 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

H1N3_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATION #3 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

H1N4_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATION #4 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

H1N5_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATION #5 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

H1N6_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATION #6 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

H1N7_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATION #7 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

H1N8_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATION #8 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

H1N9_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATION #9 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

HAD_CPOX CHILD EVER HAD 

CHICKEN POX DISEASE? Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Replaced I_HADCPX starting in 2005. This version is not imputed.

HEA1_AGE 

AGE IN MONTHS OF 

PROV-REPTD HEPATITIS 

A-CONTAINING SHOT #1

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HEA2_AGE 

AGE IN MONTHS OF 

PROV-REPTD HEPATITIS 

A-CONTAINING SHOT #2

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HEA3_AGE 

AGE IN MONTHS OF 

PROV-REPTD HEPATITIS 

A-CONTAINING SHOT #3

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HEA4_AGE 

AGE IN MONTHS OF 

PROV-REPTD HEPATITIS 

A-CONTAINING SHOT #4

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HEA5_AGE 

AGE IN MONTHS OF 

PROV-REPTD HEPATITIS 

A-CONTAINING SHOT #5

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HEA6_AGE 

AGE IN MONTHS OF 

PROV-REPTD HEPATITIS 

A-CONTAINING SHOT #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HEA7_AGE 

AGE IN MONTHS OF 

PROV-REPTD HEPATITIS 

A-CONTAINING SHOT #7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HEA8_AGE 

AGE IN MONTHS OF 

PROV-REPTD HEPATITIS 

A-CONTAINING SHOT #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HEA9_AGE 

AGE IN MONTHS OF 

PROV-REPTD HEPATITIS 

A-CONTAINING SHOT #9

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

HEP_BRTH

HEPATITIS BCONTAINING SHOT 

GIVEN AT BIRTH FLAG

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HEP_FLAG HEPATITIS B BIRTH SHOT 

DATE IMPUTATION FLAG Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HEP1_AGE 

AGE IN MONTHS OF 

PROV-REPTD HEPATITIS 

B-CONTAINING SHOT #1

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HEP2_AGE 

AGE IN MONTHS OF 

PROV-REPTD HEPATITIS 

B-CONTAINING SHOT #2

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HEP3_AGE 

AGE IN MONTHS OF 

PROV-REPTD HEPATITIS 

B-CONTAINING SHOT #3

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HEP4_AGE 

AGE IN MONTHS OF 

PROV-REPTD HEPATITIS 

B-CONTAINING SHOT #4

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HEP5_AGE 

AGE IN MONTHS OF 

PROV-REPTD HEPATITIS 

B-CONTAINING SHOT #5

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HEP6_AGE 

AGE IN MONTHS OF 

PROV-REPTD HEPATITIS 

B-CONTAINING SHOT #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HEP7_AGE 

AGE IN MONTHS OF 

PROV-REPTD HEPATITIS 

B-CONTAINING SHOT #7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HEP8_AGE 

AGE IN MONTHS OF 

PROV-REPTD HEPATITIS 

B-CONTAINING SHOT #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HEP9_AGE 

AGE IN MONTHS OF 

PROV-REPTD HEPATITIS 

B-CONTAINING SHOT #9

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

HH_DTP 

HH REPORT OF NUMBER 

OF DT-CONTAINING 

SHOTS RECEIVED

Y Y Y Y Y Y 

Added in 2006 as a partial replacement 

for the "FULL" and "C_" variables. 

Dropped in 2012 due to questionnaire 

changes. 

HH_FLU 

HH REPORT OF NUMBER 

OF SEASONAL 

INFLUENZA 

VACCINATIONS 

RECEIVED IN THE 12 

MONTHS PRIOR TO 

INTERVIEW

Y Y Y 

Influenza questions added to the HH 

questionnaire starting in 2007. Dropped 

in 2009 due to mid-year questionnaire 

changes. Reinstated in 2010. Dropped 

again in 2011 due to mid-year 

questionnaire changes.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

HH_H1N 

HH REPORT OF NUMBER 

OF MONOVALENT 2009 

H1N1 INFLUENZA 

VACCINATIONS 

RECEIVED IN THE 12 

MONTHS PRIOR TO 

INTERVIEW

Y 

H1N1 influenza questions added to the 

HH questionnaire starting in 2009. 

Introduced in the PUF in 2010. 

Dropped in 2011 due to mid-year 

questionnaire changes.

HH_HEPB 

HH REPORT OF NUMBER 

OF HEPATITIS BCONTAINING SHOTS 

RECEIVED

Y Y Y Y Y Y 

Added in 2006 as a partial replacement 

for the "FULL" and "C_" variables. 

Dropped in 2012 due to questionnaire 

changes. 

HH_HIB 

HH REPORT OF NUMBER 

OF HIB-CONTAINING 

SHOTS RECEIVED

Y Y Y Y Y Y 

Added in 2006 as a partial replacement 

for the "FULL" and "C_" variables. 

Dropped in 2012 due to questionnaire 

changes. 

HH_MCV 

HH REPORT OF NUMBER 

OF MEASLESCONTAINING SHOTS 

RECEIVED

Y Y Y Y Y Y 

Added in 2006 as a partial replacement 

for the "FULL" and "C_" variables. 

Dropped in 2012 due to questionnaire 

changes. 

HH_POL 

HH REPORT OF NUMBER 

OF POLIO-CONTAINING 

SHOTS RECEIVED

Y Y Y Y Y Y 

Added in 2006 as a partial replacement 

for the "FULL" and "C_" variables. 

Dropped in 2012 due to questionnaire 

changes. 

HH_VRC 

HH REPORT OF NUMBER 

OF VARICELLACONTAINING SHOTS 

RECEIVED

Y Y Y Y Y Y 

Added in 2006 as a partial replacement 

for the "FULL" and "C_" variables. 

Dropped in 2012 due to questionnaire 

changes. 

HIB1_AGE 

AGE IN MONTHS OF 

PROV-REPTD HIBCONTAINING SHOT #1Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HIB2_AGE 

AGE IN MONTHS OF 

PROV-REPTD HIBCONTAINING SHOT #2Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HIB3_AGE 

AGE IN MONTHS OF 

PROV-REPTD HIBCONTAINING SHOT #3Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HIB4_AGE 

AGE IN MONTHS OF 

PROV-REPTD HIBCONTAINING SHOT #4Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HIB5_AGE 

AGE IN MONTHS OF 

PROV-REPTD HIBCONTAINING SHOT #5Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HIB6_AGE 

AGE IN MONTHS OF 

PROV-REPTD HIBCONTAINING SHOT #6Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

HIB7_AGE 

AGE IN MONTHS OF 

PROV-REPTD HIBCONTAINING SHOT #7Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HIB8_AGE 

AGE IN MONTHS OF 

PROV-REPTD HIBCONTAINING SHOT #8Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

HIB9_AGE 

AGE IN MONTHS OF 

PROV-REPTD HIBCONTAINING SHOT #9Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

HUTD4313 HOUSEHOLD REPORT OF 

4:3:1:3 UTD (UP-TO-DATE) Y 

Dropped starting in 2005 because this 

variable is redundant with variable 

ALL4SHOT.

I_HADCPX DID CHILD EVER HAVE 

CHICKEN POX? Y Replaced by HAD_CPOX starting in 2005.

I_HISP_K HISPANIC ORIGIN OF 

CHILD: IMPUTED Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

IAGECPXR 

AGE IN MONTHS WHEN 

CHILD HAD CHICKEN 

POX (RECODE)

Y Replaced by AGECPOXR starting in 

2005.

INCPORAR INCOME TO POVERTY 

RATIO (RECODE) Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

Replaced INCPORAT starting in 2005. 

INCPORAT used categories whereas 

INCPORAR is continuous. 

INCPORAR has been top- and bottomcoded.

INCPORAR_I 

INCOME TO POVERTY 

RATIO: IMPUTED 

(RECODE)

Y Y Y Y Y Y Imputed version of INCPORAR added 

in 2016.

INCPORAT INCOME TO POVERTY 

RATIO Y Replaced by INCPORAR starting in 2005.

INCPOV1 POVERTY STATUS Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

Replaced INCPOV1R starting in 2005. 

INCPOV1R used two categories 

whereas INCPOV1 uses three.

INCPOV1R POVERTY STATUS 

(RECODE) Y Replaced by INCPOV1 starting in 2005.

INCQ298A FAMILY INCOME 

CATEGORIES (RECODE) Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

Replaced INCQ298R starting in 2005. 

INCQ298A uses different categories 

than were used by INCQ298R.

INCQ298R FAMILY INCOME 

CATEGORIES (RECODE) Y Replaced by INCQ298A starting in 2005.

INOPHONR 

LENGTH OF 

INTERRUPTION IN 

TELEPHONE SERVICE IN 

DAYS (RECODE)

Y Y Y Y Y Y Dropped starting in 2010 due to 

questionnaire change.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

INS_1 

IS CHILD COVERED BY 

HEALTH INSURANCE 

PROVIDED THROUGH 

EMPLOYER OR UNION?

Y Y Y Y Y Y Y Y Y 

Health insurance questions were added 

to the questionnaire in 2006 and first 

included on the PUF in 2007. Replaced 

with INS_STAT_I and INS_BREAK_I 

in 2016.

INS_11 

ANY TIME WHEN CHILD 

WAS NOT COVERED BY 

ANY HEALTH 

INSURANCE? 

Y Y Y Y Y Y Y Y Y 

Health insurance questions were added 

to the questionnaire in 2006 and first 

included on the PUF in 2007. Replaced 

with INS_STAT_I and INS_BREAK_I 

in 2016.

INS_2 IS CHILD COVERED BY 

ANY MEDICAID PLAN? Y Y Y Y Y Y Y Y Y 

Health insurance questions were added 

to the questionnaire in 2006 and first 

included on the PUF in 2007. Replaced 

with INS_STAT_I and INS_BREAK_I 

in 2016.

INS_3 IS CHILD COVERED BY SCHIP? Y Y Y Y Y Y Y Y Y 

Health insurance questions were added 

to the questionnaire in 2006 and first 

included on the PUF in 2007. Replaced 

with INS_STAT_I and INS_BREAK_I 

in 2016.

INS_3A

IS CHILD COVERED BY 

ANY MEDICAID PLAN OR 

S-CHIP? 

Y Y Y Y Y Y Y Y Y 

Health insurance questions were added 

to the questionnaire in 2006 and first 

included on the PUF in 2007. Replaced 

with INS_STAT_I and INS_BREAK_I 

in 2016.

INS_4

IS CHILD COVERED BY 

INDIAN HEALTH 

SERVICE?

Y Y 

Health insurance questions were added 

to the questionnaire in 2006 and first 

included on the PUF in 2007. Replaced 

by INS_4_5 starting in 2009.

INS_4_5

IS CHILD COVERED BY 

INDIAN HEALTH 

SERVICE, MILITARY 

HEALTH CARE, TRICARE, 

CHAMPUS, OR CHAMPVA? 

Y Y Y Y Y Y Y 

Replaced INS_4 and INS_5 starting in 

2009. Replaced with INS_STAT_I and 

INS_BREAK_I in 2016.

INS_5 

IS CHILD COVERED BY 

MILITARY HEALTH CARE, 

TRICARE, CHAMPUS, OR 

CHAMP-VA? 

Y Y 

Health insurance questions were added 

to the questionnaire in 2006 and first 

included on the PUF in 2007. Replaced 

by INS_4_5 starting in 2009.

INS_6 

IS CHILD COVERED BY 

ANY OTHER HEALTH 

INSURANCE OR HEALTH 

CARE PLAN?

Y Y Y Y Y Y Y Y Y 

Health insurance questions were added 

to the questionnaire in 2006 and first 

included on the PUF in 2007. Replaced 

with INS_STAT_I and INS_BREAK_I 

in 2016.

INS_BREAK_I 

CONTINUITY OF 

INSURANCE COVERAGE 

SINCE BIRTH: IMPUTED

Y Y Y Y Y Y Replaced INS_1-INS_11 starting in 

2016.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

INS_STAT_I INSURANCE STATUS: 

IMPUTED Y 

Replaced INS_1-INS_11 starting in 

2016. Replaced by INS_STAT2_I 

starting in 2017.

INS_STAT2_I

INSURANCE STATUS 

(PRIVATE ONLY/ANY 

MEDICAID/OTHER 

INSURANCE/UNINSURED): 

IMPUTED

Y Y Y Y Y Replaced INS_STAT_I starting in 

2017.

INTRP

PHONE INTERRUPTION OF 

7 DAYS OR MORE IN PAST 

YEAR? 

Y Y Y Y Y Y Y Y Y Y Y Y Dropped starting in 2016 due to 

questionnaire change.

ITRUEIAP IAP AREA OF CURRENT 

RESIDENCE Y Replaced by ESTIAP in 2005 because estimation areas were modified. 

LANGUAGE 

LANGUAGE IN WHICH 

INTERVIEW WAS 

CONDUCTED 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

M_AGEGRP AGE OF MOTHER 

CATEGORIES (RECODE) Y Y Y Y Y Y Y Y Y Y Y Y Replaced by M_AGEGRP2 starting in 2016.

M_AGEGRP2 

AGE OF MOTHER 

CATEGORIES: IMPUTED 

(RECODE)

Y Y Y Y Y Y Replaced M_AGEGRP starting in 

2016.

MARITAL

MARITAL STATUS OF 

MOTHER CATEGORIES 

(RECODE)

Y Y Y Y Y Replaced by MARITAL2 starting in 

2009.

MARITAL2

MARITAL STATUS OF 

MOTHER: IMPUTED

(RECODE)

Y Y Y Y Y Y Y Y Y Y Y Y Y Replaced MARITAL starting in 2009.

MMR1_AGE

AGE IN MONTHS OF 

PROV-REPTD MEASLESCONTAINING SHOT #1Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

MMR2_AGE

AGE IN MONTHS OF 

PROV-REPTD MEASLESCONTAINING SHOT #2Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

MMR3_AGE

AGE IN MONTHS OF 

PROV-REPTD MEASLESCONTAINING SHOT #3Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

MMR4_AGE

AGE IN MONTHS OF 

PROV-REPTD MEASLESCONTAINING SHOT #4Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

MMR5_AGE

AGE IN MONTHS OF 

PROV-REPTD MEASLESCONTAINING SHOT #5Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

MMR6_AGE

AGE IN MONTHS OF 

PROV-REPTD MEASLESCONTAINING SHOT #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

MMR7_AGE

AGE IN MONTHS OF 

PROV-REPTD MEASLESCONTAINING SHOT #7Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

MMR8_AGE

AGE IN MONTHS OF 

PROV-REPTD MEASLESCONTAINING SHOT #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

MMR9_AGE

AGE IN MONTHS OF 

PROV-REPTD MEASLESCONTAINING SHOT #9Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

MOBIL

GEOGRAPHIC MOBILITY 

STATUS: STATE OF 

RESIDENCE OF CHILD AT 

BIRTH VERSUS CURRENT 

STATE 

Y Replaced by MOBIL_I starting in 

2005.

MOBIL_I

GEOGRAPHIC MOBILITY 

STATUS: STATE OF 

RESIDENCE OF CHILD AT 

BIRTH VERSUS CURRENT 

STATE: IMPUTED

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Replaced MOBIL starting in 2005. 

This version is imputed.

MP1_AGE 

AGE IN MONTHS OF 

PROV-REPTD MUMPSONLY SHOT #1Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

MP2_AGE 

AGE IN MONTHS OF 

PROV-REPTD MUMPSONLY SHOT #2Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

MP3_AGE 

AGE IN MONTHS OF 

PROV-REPTD MUMPSONLY SHOT #3Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

MP4_AGE 

AGE IN MONTHS OF 

PROV-REPTD MUMPSONLY SHOT #4Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

MP5_AGE 

AGE IN MONTHS OF 

PROV-REPTD MUMPSONLY SHOT #5Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

MP6_AGE 

AGE IN MONTHS OF 

PROV-REPTD MUMPSONLY SHOT #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

MP7_AGE 

AGE IN MONTHS OF 

PROV-REPTD MUMPSONLY SHOT #7Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

MP8_AGE 

AGE IN MONTHS OF 

PROV-REPTD MUMPSONLY SHOT #8Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

MP9_AGE 

AGE IN MONTHS OF 

PROV-REPTD MUMPSONLY SHOT #9Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

MPR1_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

(MUMPS/RUBELLA)-ONLY 

SHOT #1

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

MPR2_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

(MUMPS/RUBELLA)-ONLY 

SHOT #2

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

MPR3_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

(MUMPS/RUBELLA)-ONLY 

SHOT #3

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

MPR4_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

(MUMPS/RUBELLA)-ONLY 

SHOT #4

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

MPR5_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

(MUMPS/RUBELLA)-ONLY 

SHOT #5

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

MPR6_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

(MUMPS/RUBELLA)-ONLY 

SHOT #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

MPR7_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

(MUMPS/RUBELLA)-ONLY 

SHOT #7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

MPR8_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

(MUMPS/RUBELLA)-ONLY 

SHOT #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

MPR9_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

(MUMPS/RUBELLA)-ONLY 

SHOT #9

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

N_PRVR 

NUMBER OF PROVIDERS 

RESPONDING WITH 

VACCINATION DATA FOR 

CHILD (RECODE)

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

NUM_CELLS_HH

NUMBER OF WORKING 

CELL PHONES 

HOUSEHOLD MEMBERS 

HAVE AVAILABLE FOR 

PERSONAL USE

Y Y Y Y Y Y Y Y Y Y Y Y Y Question added to household 

questionnaire in 2009.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

NUM_CELLS_PARENTS

NUMBER OF WORKING 

CELL PHONES USUALLY 

USED BY PARENTS OR 

GUARDIANS 

Y Y Y Y Y Y Y Y Y Y Y Y Y Question added to household 

questionnaire in 2009.

NUM_PHONE 

NUMBER OF 

RESIDENTIAL 

TELEPHONE NUMBERS IN 

HOUSEHOLD 

(EXCLUDING CELL 

PHONES) 

Y Y Y Y Y Y Y Y Y Y Y Y Y Question added to household 

questionnaire in 2009.

P_NUHEPX 

NUMBER OF HEPATITIS BONLY SHOTS BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUHIBX 

NUMBER OF HIB-ONLY 

SHOTS BY 36 MONTHS OF 

AGE DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

Added in 2006 so that each vaccine 

type on the IHQ has a corresponding 

shot count variable.

P_NUHPHB 

NUMBER OF HEPATITIS 

B/HIB COMBO SHOTS BY 

36 MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUM1L 

NUMBER OF 

MONOVALENT 2009 H1N1

INFLUENZA 

VACCINATIONS OF 

UNKNOWN TYPE BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

P_NUM1M 

NUMBER OF 

MONOVALENT 2009 H1N1 

INFLUENZA SPRAY 

VACCINATIONS BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

P_NUM1N

NUMBER OF INJECTED 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATIONS BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

P_NUMDAH 

NUMBER OF DTAP/HIB 

COMBO SHOTS BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMDHB 

NUMBER OF DTP/HIB 

CONTAINING SHOTS 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Dropped in 2009 due to change to IHQ 

shotgrid.

P_NUMDHI 

NUMBER OF 

DTAP/HEPB/IPV COMBO 

SHOTS BY 36 MONTHS OF 

AGE DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

Added in 2006 so that each vaccine 

type on the IHQ has a corresponding 

shot count variable.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

P_NUMDHM 

NUMBER OF DTP/HIB 

COMBO SHOTS 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Dropped in 2009 due to change to IHQ 

shotgrid.

P_NUMDIH 

NUMBER OF 

DTAP/IPV/HIB COMBO 

SHOTS BY 36 MONTHS OF 

AGE DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Added in 2009 due to change to IHQ 

shotgrid.

P_NUMDIHB 

NUMBER OF 

DTAP/IPV/HIB/HEPB 

SHOTS BY 19-35 MONTHS 

OF AGE DETERMINED 

FROM PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE MAX OF 

HOUSEHOLD 

INTERVIEW DATE AND 

ELIGIBILITY DATE.

Y Added in 2021 to reflect new IHQ 

grid shot type.

P_NUMDTA 

NUMBER OF DTAP-ONLY 

SHOTS BY 36 MONTHS OF 

AGE DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMDTM 

NUMBER OF DT-ONLY 

SHOTS DETERMINED 

FROM PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Dropped in 2009 due to change to IHQ 

shotgrid.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

P_NUMDTP 

NUMBER OF DTCONTAINING SHOTS BY 

36 MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMFLU 

NUMBER OF SEASONAL 

FLU-CONTAINING 

VACCINATIONS BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMFLUL 

NUMBER OF SEASONAL 

FLU-CONTAINING 

VACCINATIONS OF 

UNKNOWN TYPE BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2008, influenza type boxes 

were added to the IHQ shot grid.

P_NUMFLUM 

NUMBER OF SEASONAL 

FLU SPRAY 

VACCINATIONS BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2008, influenza type boxes 

were added to the IHQ shot grid.

P_NUMFLUN 

NUMBER OF INJECTED 

SEASONAL FLU 

VACCINATIONS BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2008, influenza type boxes 

were added to the IHQ shot grid.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

P_NUMH1N 

NUMBER OF 

MONOVALENT 2009 H1N1

INFLUENZA 

VACCINATIONS BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

P_NUMH2 

NUMBER OF HIB-SANOFI 

or HIBGLAXOSMITHKLINE 

SHOTS BY 36 MONTHS OF 

AGE DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y 

Added in 2009 due to change to IHQ 

shotgrid. Replaced by P_NUMHG and 

P_NUMHS starting in 2010.

P_NUMHEA 

NUMBER OF HEPATITIS 

A-CONTAINING SHOTS BY 

36 MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMHEN 

NUMBER OF HEPATITIS BCONTAINING SHOTS OF 

UNKNOWN TYPE BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

Added in 2006 so that each vaccine 

type on the IHQ has a corresponding 

shot count variable.

P_NUMHEP 

NUMBER OF HEPATITIS BCONTAINING SHOTS BY 

36 MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

P_NUMHG 

NUMBER OF HIBGLAXOSMITHKLINE 

SHOTS BY 36 MONTHS OF 

AGE DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Replaced P_NUMH2 starting in 2010

due to a change to the IHQ shotgrid. 

P_NUMHHY 

NUMBER OF HIB-MENCY 

SHOTS BY 36 MONTHS OF 

AGE DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Added in 2014 due to change in IHQ 

shotgrid.

P_NUMHIB 

NUMBER OF HIBCONTAINING SHOTS BY 

36 MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMHIN 

NUMBER OF HIBCONTAINING SHOTS OF 

UNKNOWN TYPE BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

Added in 2006 so that each vaccine 

type on the IHQ has a corresponding 

shot count variable.

P_NUMHION 

NUMBER OF HIB-ONLY 

SHOTS OF UNKNOWN 

TYPE BY 36 MONTHS OF 

AGE DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Added in 2009 due to change to IHQ 

shotgrid.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

P_NUMHM 

NUMBER OF HIB-MERCK 

SHOTS BY 36 MONTHS OF 

AGE DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Added in 2009 due to change to IHQ 

shotgrid.

P_NUMHS 

NUMBER OF HIB-SANOFI 

SHOTS BY 36 MONTHS OF 

AGE DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Replaced P_NUMH2 starting in 2010

due to a change in the IHQ shotgrid. 

P_NUMIPV 

NUMBER OF IPV-ONLY 

SHOTS BY 36 MONTHS OF 

AGE DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMMCN 

NUMBER OF MEASLESCONTAINING SHOTS OF 

UNKNOWN TYPE BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

Added in 2006 so that each vaccine 

type on the IHQ has a corresponding 

shot count variable.

P_NUMMMR 

NUMBER OF MEASLESCONTAINING SHOTS BY 

36 MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

P_NUMMMRX 

NUMBER OF MMR-ONLY 

SHOTS BY 36 MONTHS OF 

AGE DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

Added in 2006 so that each vaccine 

type on the IHQ has a corresponding 

shot count variable.

P_NUMMMX 

NUMBER OF MMRCONTAINING SHOTS BY 

36 MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMMP 

NUMBER OF MUMPSONLY SHOTS BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMMPR 

NUMBER OF 

(MUMPS/RUBELLA)-ONLY 

SHOTS BY 36 MONTHS OF 

AGE DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMMRV 

NUMBER OF 

MMR/VARICELLA COMBO 

SHOTS BY 36 MONTHS OF 

AGE DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

Added in 2006 so that each vaccine 

type on the IHQ has a corresponding 

shot count variable.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

P_NUMMS 

NUMBER OF MEASLESONLY SHOTS BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMMSM 

NUMBER OF 

MEASLES/MUMPS COMBO 

SHOTS BY 36 MONTHS OF 

AGE DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMMSR 

NUMBER OF 

MEASLES/RUBELLA 

COMBO SHOTS BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMOLN 

NUMBER OF POLIO 

SHOTS OF UNKNOWN 

TYPE BY 36 MONTHS OF 

AGE DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMOPV 

NUMBER OF OPV-ONLY 

SHOTS BY 36 MONTHS OF 

AGE DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

P_NUMPCC 

NUMBER OF 

PNEUMOCOCCAL 

CONJUGATE SHOTS BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMPCC13 

NUMBER OF 

PNEUMOCOCCAL 

CONJUGATE-13 SHOTS BY 

36 MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Added in 2010 due to new PCV 

vaccination recommendations.

P_NUMPCC7 

NUMBER OF 

PNEUMOCOCCAL 

CONJUGATE-7 SHOTS BY 

36 MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Added in 2010 due to new PCV 

vaccination recommendations.

P_NUMPCCN 

NUMBER OF 

PNEUMOCOCCAL 

CONJUGATE SHOTS OF 

UNKNOWN TYPE BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Added in 2010 due to new PCV 

vaccination recommendations.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

P_NUMPCN 

NUMBER OF 

PNEUMOCOCCAL SHOTS 

OF UNKNOWN TYPE BY 

36 MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMPCP 

NUMBER OF 

PNEUMOCOCCAL 

POLYSACCHARIDE 

SHOTS BY 36 MONTHS OF 

AGE DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMPCV 

NUMBER OF 

PNEUMOCOCCALCONTAINING SHOTS BY 

36 MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMPOL 

NUMBER OF POLIOCONTAINING SHOTS BY 

36 MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMRB 

NUMBER OF RUBELLAONLY SHOTS BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

P_NUMRG 

NUMBER OF ROTARIXGSK SHOTS BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2009, rotavirus type boxes 

were added to the IHQ shot grid.

P_NUMRM 

NUMBER OF ROTATEQMERCK SHOTS BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2009, rotavirus type boxes 

were added to the IHQ shot grid.

P_NUMRO 

NUMBER OF ROTAVIRUS 

SHOTS OF UNKNOWN 

TYPE BY 36 MONTHS OF 

AGE DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2009, rotavirus type boxes 

were added to the IHQ shot grid.

P_NUMROT 

NUMBER OF ROTAVIRUSCONTAINING SHOTS BY 

36 MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMTPM 

NUMBER OF DTP-ONLY 

SHOTS DETERMINED 

FROM PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Dropped in 2009 due to change to IHQ 

shotgrid.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

P_NUMTPN 

NUMBER OF DTCONTAINING SHOTS OF 

UNKNOWN TYPE BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMVRC 

NUMBER OF VARICELLACONTAINING SHOTS BY 

36 MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_NUMVRN 

NUMBER OF VARICELLACONTAINING SHOTS OF 

UNKNOWN TYPE BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

Added in 2006 so that each vaccine 

type on the IHQ has a corresponding 

shot count variable.

P_NUMVRX 

NUMBER OF VARICELLAONLY SHOTS BY 36 

MONTHS OF AGE 

DETERMINED FROM 

PROVIDER INFO, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HH INTERVIEW 

DATE. 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

Added in 2006 so that each vaccine 

type on the IHQ has a corresponding 

shot count variable.

P_U12VRC 

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 1+ 

VARICELLA-CONTAINING 

SHOT AT 12+ MONTHS OF 

AGE, BY 36 MONTHS OF 

AGE, EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

P_UTD331 

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 3:3:1 BY 36 

MONTHS OF AGE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_UTD431 

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 4:3:1 BY 36 

MONTHS OF AGE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_UTD431H_ROUT_S 

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 4:3:1:3 BY 

36 MONTHS OF AGE, 

USING THE ROUTINE, 

STRICT DEFINITION OF 

HIB UTD, EXCLUDING 

ANY VACCINATIONS 

AFTER THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Added in 2009 due to new Hib 

vaccination recommendations.

P_UTD431H3_ROUT_S

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 4:3:1:3:3 

BY 36 MONTHS OF AGE, 

USING THE ROUTINE, 

STRICT DEFINITION OF 

HIB UTD, EXCLUDING 

ANY VACCINATIONS 

AFTER THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Added in 2009 due to new Hib 

vaccination recommendations.

P_UTD431H31_ROUT_S

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 4:3:1:3:3:1 

BY 36 MONTHS OF AGE 

(INCLUDES 1+ 

VARICELLA-CONTAINING 

AT AGE 12+ MTHS) USING 

THE ROUTINE, STRICT 

DEFINITION OF HIB UTD, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Added in 2009 due to new Hib 

vaccination recommendations.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

P_UTD431H313_ROUT_S

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 

4:3:1:3:3:1:3 BY 36 

MONTHS OF AGE 

(INCLUDES 1+ 

VARICELLA-CONTAINING 

AT AGE 12+ MTHS) USING 

THE ROUTINE, STRICT 

DEFINITION OF HIB UTD, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Added in 2009 due to new Hib 

vaccination recommendations.

P_UTD431H314_ROUT_S

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 

4:3:1:3:3:1:4 BY 36 

MONTHS OF AGE 

(INCLUDES 1+ 

VARICELLA-CONTAINING 

AT AGE 12+ MTHS) USING 

THE ROUTINE, STRICT 

DEFINITION OF HIB UTD, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Added in 2009 due to new Hib 

vaccination recommendations.

P_UTDFL1 

UTD (UP-TO-DATE) FLAG

FOR PROVIDER 

SEASONAL INFLUENZA 

VARIABLE 1 BY 36 

MONTHS OF AGE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Dropped starting in 2014 due to change 

in ACIP recommendations.

P_UTDFL2 

UTD (UP-TO-DATE) FLAG

FOR PROVIDER 

SEASONAL INFLUENZA 

VARIABLE 2 BY 36 

MONTHS OF AGE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Dropped starting in 2014 due to change 

in ACIP recommendations.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

P_UTDFL3 

UTD (UP-TO-DATE) FLAG

FOR PROVIDER 

SEASONAL INFLUENZA 

VARIABLE 3 BY 36 

MONTHS OF AGE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y 

Added in 2007 due to new influenza 

vaccination recommendations. Dropped 

starting in 2014 due to change in ACIP 

recommendations. 

P_UTDH1N_1 

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 1+ 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATION BY 36 

MONTHS OF AGE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE AND 

EXCLUDING 

VACCINATIONS GIVEN 

PRIOR TO 10/5/2009.

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

P_UTDH1N_2 

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 2+ 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATIONS BY 36 

MONTHS OF AGE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE AND 

EXCLUDING 

VACCINATIONS GIVEN 

PRIOR TO 10/5/2009.

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

P_UTDHEP 

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 3+ 

HEPATITIS BCONTAINING SHOTS BY 

36 MONTHS OF AGE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

P_UTDHEPA1 

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 1+ 

HEPATITIS ACONTAINING SHOTS BY 

36 MONTHS OF AGE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Added in 2011 to aid analysis. 

P_UTDHEPA2 

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 2+ 

HEPATITIS ACONTAINING SHOTS BY 

36 MONTHS OF AGE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Added in 2010 to aid analysis. 

P_UTDHIB 

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 3+ HIBCONTAINING SHOTS BY 

36 MONTHS OF AGE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_UTDHIB_ROUT_S 

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 3+ HIB 

DOSES BY 36 MONTHS OF 

AGE, BASED ON THE 

ROUTINE (NONSHORTAGE) HIB 

RECOMMENDATIONS 

AND A STRICT 

TREATMENT OF HIB 

SHOTS OF UNKNOWN 

TYPE, EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Added in 2009 due to new Hib 

vaccination recommendations.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

P_UTDHIB_SHORT_S 

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 3+ HIB 

DOSES BY 36 MONTHS OF 

AGE, BASED ON THE HIB 

SHORTAGE 

RECOMMENDATIONS 

AND A STRICT 

TREATMENT OF HIB 

SHOTS OF UNKNOWN 

TYPE, EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Added in 2009 due to new Hib 

vaccination recommendations.

P_UTDMCV 

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 1+ 

MEASLES-CONTAINING 

SHOT BY 36 MONTHS OF 

AGE, EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_UTDMMX 

UTD (UP-TO-DATE) FLAG

FOR PROVIDER 1+ MMR 

COMBO SHOT BY 36 

MONTHS OF AGE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_UTDPC3 

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 3+ 

PNEUMOCOCCALCONTAINING SHOTS BY 

36 MONTHS OF AGE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_UTDPCV 

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 4+ 

PNEUMOCOCCALCONTAINING SHOTS BY 

36 MONTHS OF AGE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

P_UTDPCVB13 

UTD (UP-TO-DATE) 

INDICATOR FOR 

PROVIDER 1+ 

PNEUMOCOCCAL 

VACCINATIONS OF TYPE 

CONJUGATE-13, GIVEN 4+ 

DOSES OF TYPE 

CONJUGATE-7, BY 36 

MONTHS OF AGE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Added in 2010 due to new PCV 

vaccination recommendations.

P_UTDPOL 

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 3+ POLIOCONTAINING SHOTS BY 

36 MONTHS OF AGE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_UTDROT_S 

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 3+ 

ROTAVIRUS DOSES BY 36 

MONTHS OF AGE, BASED 

ON A STRICT 

TREATMENT OF 

ROTAVIRUS 

VACCINATIONS OF 

UNKNOWN TYPE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Added in 2009 to aid analysis. 

P_UTDTP3 

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 3+ DTCONTAINING SHOTS BY 

36 MONTHS OF AGE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

P_UTDTP4 

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 4+ DTCONTAINING SHOTS BY 

36 MONTHS OF AGE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

PCV1_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

PNEUMOCOCCALCONTAINING SHOT #1

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

PCV2_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

PNEUMOCOCCALCONTAINING SHOT #2

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

PCV3_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

PNEUMOCOCCALCONTAINING SHOT #3

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

PCV4_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

PNEUMOCOCCALCONTAINING SHOT #4

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

PCV5_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

PNEUMOCOCCALCONTAINING SHOT #5

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

PCV6_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

PNEUMOCOCCALCONTAINING SHOT #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

PCV7_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

PNEUMOCOCCALCONTAINING SHOT #7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

PCV8_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

PNEUMOCOCCALCONTAINING SHOT #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

PCV9_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

PNEUMOCOCCALCONTAINING SHOT #9

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

PDAT CHILD HAS ADEQUATE 

PROVIDER DATA Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

POL1_AGE 

AGE IN MONTHS OF 

PROV-REPTD POLIOCONTAINING SHOT #1Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

POL2_AGE 

AGE IN MONTHS OF 

PROV-REPTD POLIOCONTAINING SHOT #2Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

POL3_AGE 

AGE IN MONTHS OF 

PROV-REPTD POLIOCONTAINING SHOT #3Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

POL4_AGE 

AGE IN MONTHS OF 

PROV-REPTD POLIOCONTAINING SHOT #4Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

POL5_AGE 

AGE IN MONTHS OF 

PROV-REPTD POLIOCONTAINING SHOT #5Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

POL6_AGE 

AGE IN MONTHS OF 

PROV-REPTD POLIOCONTAINING SHOT #6Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

POL7_AGE 

AGE IN MONTHS OF 

PROV-REPTD POLIOCONTAINING SHOT #7Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

POL8_AGE 

AGE IN MONTHS OF 

PROV-REPTD POLIOCONTAINING SHOT #8Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

POL9_AGE 

AGE IN MONTHS OF 

PROV-REPTD POLIOCONTAINING SHOT #9Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

PROV_FAC PROVIDER FACILITY 

TYPES: IMPUTED Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

PROVWT 

WEIGHT FOR CHILDREN 

WITH ADEQUATE 

PROVIDER DATA AND 

UNVACCINATED 

CHILDREN (EXCLUDING 

U.S. VIRGIN ISLANDS)

Y Y Y Y Y Y 

Added in 2005 to replace WGT. 

Replaced by PROVWT_LL in 2011 

due to addition of dual-frame weights.

PROVWT_C 

FINAL SINGLE-FRAME 

CELL-PHONE PROVIDERPHASE WEIGHT 

(EXCLUDES 

TERRITORIES)

Y Y Y Y Replaced PROVWT_D in 2018 due to 

removal of the landline sample.

PROVWT_C_TERR

FINAL SINGLE-FRAME 

CELL-PHONE PROVIDERPHASE WEIGHT 

INCLUDING TERRITORIES

Y Y Y 

Added in 2019 to replace 

PROVWT_D_TERR due to removal of 

the landline sample

PROVWT_D

FINAL DUAL-FRAME 

PROVIDER-PHASE 

WEIGHT (EXCLUDES 

TERRITORIES)

Y Y Y Y Y Y Y 

Added in 2011 as dual-frame weight.

Replaced by PROVWT_C in 2018 due 

to removal of the landline sample.

PROVWT_LL 

LANDLINE-FRAME 

WEIGHT FOR CHILDREN 

WITH ADEQUATE 

PROVIDER DATA AND 

UNVACCINATED 

CHILDREN (EXCLUDING 

U.S. VIRGIN ISLANDS)

Y 

Replaced PROVWT in 2011 to 

distinguish from new dual-frame 

weight PROVWT_D. Removed in 

2012. 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

PROVWTVI 

WEIGHT FOR CHILDREN 

WITH ADEQUATE 

PROVIDER DATA AND 

UNVACCINATED 

CHILDREN (INCLUDING 

U.S. VIRGIN ISLANDS)

Y Y 

Added in 2009 to include U.S. Virgin 

Island sample. Replaced by 

PROVWTVI_LL in 2011 due to 

addition of dual-frame weights. 

PROVWTVI_D 

COMBINATION OF THE 

DUAL-FRAME WEIGHT 

FOR CHILDREN IN THE 

U.S. PROPER AND 

LANDLINE WEIGHT FOR 

CHILDREN IN THE U.S. 

VIRGIN ISLANDS FOR 

CHILDREN WITH 

ADEQUATE PROVIDER 

DATA AND 

UNVACCINATED 

CHILDREN

Y 

Replaced PROVWTVI_LL in 2012. 

Replaced with PROVWTVIGU_D in 

2013 due to the addition of Guam 

sample. 

PROVWTVIGU_D 

THE DUAL-FRAME 

WEIGHT FOR CHILDREN 

IN THE U.S. PROPER, THE 

U.S. VIRGIN ISLANDS 

AND GUAM FOR 

CHILDREN WITH 

ADEQUATE PROVIDER 

DATA AND 

UNVACCINATED 

CHILDREN

Y 

Replaced PROVWTVI_D in 2013 due 

to the addition of Guam sample. 

Replaced with PROVWT_D_TERR in 

2014 due to addition of Puerto Rico 

sample. 

PROVWT_D_TERR 

FINAL DUAL-FRAME 

PROVIDER-PHASE 

WEIGHT INCLUDING 

TERRITORIES

Y Y Y 

Replaced PROVWTVIGU_D in 2014 

due to addition of Puerto Rico sample. 

Not available on the 2017 PUF as no 

data from U.S. territories were 

included. 

PROVWTVI_LL

LANDLINE-FRAME 

WEIGHT FOR CHILDREN 

WITH ADEQUATE 

PROVIDER DATA AND 

UNVACCINATED 

CHILDREN (INCLUDING 

U.S. VIRGIN ISLANDS)

Y 

Replaced PROVWTVI in 2011. 

Replaced with dual-frame weight 

PROVWTVI_D in 2012.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

PU431_31

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 4:3:1::3:1 

(4:3:1:3:3:1 EXCLUDING 

HIB; INCLUDES 1+ 

VARICELLA AT AGE 12+ 

MTHS) BY 36 MONTHS OF 

AGE, EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Added in 2010 to aid analysis. Dropped 

in 2019.

PU431_314

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 4:3:1::3:1:4 

(4:3:1:3:3:1:4 EXCLUDING 

HIB; INCLUDES 1+ 

VARICELLA AT AGE 12+ 

MTHS) BY 36 MONTHS OF 

AGE, EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Added in 2010 to aid analysis. Dropped 

in 2019.

PU431331

UTD (UP-TO-DATE) FLAG

FOR PROVIDER 4:3:1:3:3:1 

(INCLUDES 1+ 

VARICELLA AT AGE 12+ 

MTHS) BY 36 MONTHS OF 

AGE, EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

PU4313313

UTD (UP-TO-DATE) FLAG

FOR PROVIDER 

4:3:1:3:3:1:3 (INCLUDES 1+ 

VARICELLA AT AGE 12+ 

MTHS) BY 36 MONTHS OF 

AGE, EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Added in 2007 to aid analysis. 

PU4313314

UTD (UP-TO-DATE) FLAG

FOR PROVIDER 

4:3:1:3:3:1:4 (INCLUDES 1+ 

VARICELLA AT AGE 12+ 

MTHS) BY 36 MONTHS OF 

AGE, EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Added in 2007 to aid analysis. 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

PUT43133

UTD (UP-TO-DATE) FLAG

FOR PROVIDER 4:3:1:3:3 

BY 36 MONTHS OF AGE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

PUTD4313 

UTD (UP-TO-DATE) FLAG

FOR PROVIDER 4:3:1:3 BY 

36 MONTHS OF AGE, 

EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

Q5WEB1 INTEREST IN IHQ ON 

WEBSITE PROVIDER #1 Y Question was not asked starting in 2005.

Q5WEB2 INTEREST IN IHQ ON 

WEBSITE PROVIDER #2 Y Question was not asked starting in 2005.

Q5WEB3 INTEREST IN IHQ ON 

WEBSITE PROVIDER #3 Y Question was not asked starting in 2005.

Q5WEB4 INTEREST IN IHQ ON 

WEBSITE PROVIDER #4 Y Question was not asked starting in 2005.

Q5WEB5 INTEREST IN IHQ ON 

WEBSITE PROVIDER #5 Y Question was not asked starting in 2005.

RACE_K RACE OF CHILD: 

IMPUTED (RECODE) Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

RACEETHK

RACE/ETHNICITY OF 

CHILD: IMPUTED

(RECODE)

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

RB1_AGE 

AGE IN MONTHS OF 

PROV-REPTD RUBELLAONLY SHOT #1Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

RB2_AGE 

AGE IN MONTHS OF 

PROV-REPTD RUBELLAONLY SHOT #2Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

RB3_AGE 

AGE IN MONTHS OF 

PROV-REPTD RUBELLAONLY SHOT #3Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

RB4_AGE 

AGE IN MONTHS OF 

PROV-REPTD RUBELLAONLY SHOT #4Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

RB5_AGE 

AGE IN MONTHS OF 

PROV-REPTD RUBELLAONLY SHOT #5Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

RB6_AGE 

AGE IN MONTHS OF 

PROV-REPTD RUBELLAONLY SHOT #6Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

RB7_AGE 

AGE IN MONTHS OF 

PROV-REPTD RUBELLAONLY SHOT #7Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

RB8_AGE 

AGE IN MONTHS OF 

PROV-REPTD RUBELLAONLY SHOT #8Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

RB9_AGE 

AGE IN MONTHS OF 

PROV-REPTD RUBELLAONLY SHOT #9Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

RDDWT 

HH-PHASE CHILD 

INTERVIEW WEIGHT 

(EXCLUDING U.S. VIRGIN 

ISLANDS) 

Y Y Y Y Y Y 

Added in 2005 to replace WGT_RDD. 

Replaced by RDDWT_LL in 2011 due 

to addition of dual-frame weights.

RDDWT_C 

FINAL SINGLE-FRAME 

CELLULAR PHONERDDPHASE WEIGHT 

(EXCLUDES 

TERRITORIES)

Y Y Y Y Replaced RDDWT_D in 2018 due to 

removal of the landline sample.

RDDWT_C_TERR

FINAL SINGLE-FRAME 

CELLULAR PHONERDDPHASE WEIGHT 

INCLUDING TERRITORIES

Y Y Y 

Added in 2019 to replace 

RDDWT_D_TERR due to removal of 

the landline sample.

RDDWT_D 

FINAL DUAL-FRAME 

RDD-PHASE WEIGHT 

(EXCLUDES 

TERRITORIES)

Y Y Y Y Y Y Y 

Added in 2011 as dual-frame weight. 

Replaced by RDDWT_C in 2018 due 

to removal of the landline sample.

RDDWT_LL

LANDLINE-FRAME HHPHASE CHILD INTERIVEW 

WEIGHT (EXCLUDING U.S. 

VIRGIN ISLANDS)

Y 

Replaced RDDWT in 2011 to 

distinguish from new dual-frame 

weight RDDWT_D. Removed in 2012.

RDDWTVI 

HH-PHASE CHILD 

INTERVIEW WEIGHT 

(INCLUDING U.S. VIRGIN 

ISLANDS) 

Y Y 

Added in 2009 to include U.S. Virgin 

Island sample. Replaced by 

RDDWTVI_LL in 2011 due to addition 

of dual-frame weights.

RDDWTVI_D 

COMBINATION OF THE 

DUAL-FRAME HH-PHASE 

WEIGHT FOR 

HOUSEHOLDS IN THE U.S. 

PROPER AND LANDLINE 

HH-PHASE WEIGHT FOR 

HOUSEHOLDS IN THE U.S. 

VIRGIN ISLANDS

Y 

Replaced RDDWTVI_LL in 2012. 

Replaced with RDDWTVIGU_D in 

2013 due to the addition of Guam 

sample. 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

RDDWTVIGU_D 

THE DUAL-FRAME HHPHASE WEIGHT FOR 

HOUSEHOLDS IN THE U.S. 

PROPER, THE U.S. VIRGIN 

ISLANDS AND GUAM

Y 

Replaced RDDWTVI_D in 2013 due to 

the addition of Guam sample. Replaced 

with RDDWT_D_TERR in 2014 due to 

addition of Puerto Rico sample.

RDDWT_D_TERR

FINAL DUAL-FRAME 

RDD-PHASE WEIGHT 

INCLUDING TERRITORIES

Y Y Y 

Replaced RDDWTVIGU_D in 2014 

due to addition of Puerto Rico sample. 

Not available on the 2017 PUF as no 

data from U.S. territories were 

included. 

RDDWTVI_LL

LANDLINE-FRAME HHPHASE CHILD INTERIVEW 

WEIGHT (INCLUDING U.S. 

VIRGIN ISLANDS)

Y 

Replaced RDDWTVI in 2011. 

Replaced with dual-frame weight 

RDDWTVI_D in 2012.

REGISTRY

CHILD'S PROVIDERS 

REPORTED CHILD'S 

VACCINATIONS TO 

IMMUNIZATION 

REGISTRY

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

RENT_OWN

IS HOME OWNED/BEING 

BOUGHT, RENTED, OR 

OCCUPIED BY SOME 

OTHER ARRANGEMENT?

Y Y Y Y Y Y Y Y Y Y Y Y Y 

Question added to the questionnaire 

starting in late 2008, and introduced in 

the PUF in 2009. 

ROT1_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

ROTAVIRUS-CONTAINING 

SHOT #1

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

ROT2_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

ROTAVIRUS-CONTAINING 

SHOT #2

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

ROT3_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

ROTAVIRUS-CONTAINING 

SHOT #3

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

ROT4_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

ROTAVIRUS-CONTAINING 

SHOT #4

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

ROT5_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

ROTAVIRUS-CONTAINING 

SHOT #5

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

ROT6_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

ROTAVIRUS-CONTAINING 

SHOT #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

ROT7_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

ROTAVIRUS-CONTAINING 

SHOT #7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

ROT8_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

ROTAVIRUS-CONTAINING 

SHOT #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

ROT9_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

ROTAVIRUS-CONTAINING 

SHOT #9

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

SC_431 HH SHOT CARD REPORT 

OF 4:3:1 UP-TO-DATE Y Y Y Y Y Y 

Added in 2006 as a partial replacement 

for the "FULL" and "C_" variables. 

Dropped in 2012 due to questionnaire 

changes. 

SC_4313 HH SHOT CARD REPORT 

OF 4:3:1:3 UP-TO-DATE Y Y Y Y Y Y 

Added in 2006 as a partial replacement 

for the "FULL" and "C_" variables. 

Dropped in 2012 due to questionnaire 

changes. 

SC_43133 HH SHOT CARD REPORT 

OF 4:3:1:3:3 UP-TO-DATE Y Y Y Y Y Y 

Added in 2006 as a partial replacement 

for the "FULL" and "C_" variables. 

Dropped in 2012 due to questionnaire 

changes. 

SC_DTP 

HH SHOT CARD REPORT 

OF 4+ DT-CONTAINING 

UP-TO-DATE

Y Y Y Y Y Y 

Added in 2006 as a partial replacement 

for the "FULL" and "C_" variables. 

Dropped in 2012 due to questionnaire 

changes. 

SC_HEPB 

HH SHOT CARD REPORT 

OF 3+ HEPATITIS BCONTAINING UP-TODATE 

Y Y Y Y Y Y 

Added in 2006 as a partial replacement 

for the "FULL" and "C_" variables. 

Dropped in 2012 due to questionnaire 

changes. 

SC_HIB 

HH SHOT CARD REPORT 

OF 3+ HIB-CONTAINING 

UP-TO-DATE

Y Y Y Y Y Y 

Added in 2006 as a partial replacement 

for the "FULL" and "C_" variables. 

Dropped in 2012 due to questionnaire 

changes. 

SC_MCV

HH SHOT CARD REPORT 

OF 1+ MEASLESCONTAINING UP-TODATE 

Y Y Y Y Y Y 

Added in 2006 as a partial replacement 

for the "FULL" and "C_" variables. 

Dropped in 2012 due to questionnaire 

changes. 

SC_POL 

HH SHOT CARD REPORT 

OF 3+ POLIO-CONTAINING 

UP-TO-DATE

Y Y Y Y Y Y 

Added in 2006 as a partial replacement 

for the "FULL" and "C_" variables. 

Dropped in 2012 due to questionnaire 

changes. 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

SC_VRC 

HH SHOT CARD REPORT 

OF 1+ VARICELLACONTAINING UP-TODATE 

Y Y Y Y Y Y 

Added in 2006 as a partial replacement 

for the "FULL" and "C_" variables. 

Dropped in 2012 due to questionnaire 

changes. 

SEQNUMC UNIQUE CHILD 

IDENTIFIER Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

SEQNUMHH UNIQUE HOUSEHOLD 

IDENTIFIER Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

SEX SEX OF CHILD: IMPUTED Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

SHORT 

Q1/2004 SHORT 

QUESTIONNAIRE STUDY 

FLAG 

Y There was no short questionnaire study 

starting in 2005.

STATE 

TRUE STATE OF 

RESIDENCE (STATE FIPS 

CODE) 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

STRATUM STRATUM VARIABLE FOR 

VARIANCE ESTIMATION Y Y Y Y Y Y Y Y Y Y 

Replaced STRATUM_D in 2012. 

Equal to sample frame by estimation 

area. 

STRATUM_D 

STRATUM VARIABLE FOR 

DUAL-FRAME VARIANCE 

ESTIMATION

Y 

Added in 2011. Equal to sample frame 

by estimation area. Replaced by 

STRATUM in 2012.

TEL_SAMPFRAME SAMPLE FRAME 

INDICATOR Y Added in 2011. Dropped in 2012 due to use of only dual-frame weights. 

U19_FLU_24D

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 2+ 

INFLUENZA 

VACCINATIONS AT 

LEAST 4 WEEKS-4 DAYS 

APART BY 19 MONTHS OF 

AGE, EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y New up-to-date variable added in 2020.

U1D_HEP

BIRTH DOSE HEPATITIS 

B-CONTAINING GIVEN 

FROM BIRTH TO DAY 1 

FLAG 

Y Y Y Y Y Y Y Y Y Y Y Added 2011 to aid analysis. 

U24_FLU_24D

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 2+ 

INFLUENZA 

VACCINATIONS AT 

LEAST 4 WEEKS-4 DAYS 

APART BY 24 MONTHS OF 

AGE, EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y Y Y New up-to-date variable added in 2018.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

U24_FLU3_24D

UTD (UP-TO-DATE) FLAG 

FOR PROVIDER 3+ 

INFLUENZA 

VACCINATIONS AT 

LEAST 4 WEEKS-4 DAYS 

APART BY 24 MONTHS OF 

AGE, EXCLUDING ANY 

VACCINATIONS AFTER 

THE HOUSEHOLD 

INTERVIEW DATE.

Y Y New up-to-date variable added in 2020.

U2D_HEP

BIRTH DOSE HEPATITIS 

B-CONTAINING GIVEN 

FROM BIRTH TO DAY 2 

FLAG 

Y Y Y Y Y Y Y Y Y Y Y Added 2011 to aid analysis. 

U3D_HEP 

BIRTH DOSE HEPATITIS 

B-CONTAINING GIVEN 

FROM BIRTH TO DAY 3 

FLAG 

Y Y Y Y Y Y Y Y Y Y Y Added 2011 to aid analysis. 

VFC_I DERIVED: IS CHILD VFC 

ELIGIBLE? Y Y Y 

Added in 2009 to aid analysis. Dropped 

starting in 2012 due to a change in the 

IHQ. 

VFC_ORDER 

DO CHILD'S PROVIDERS 

ORDER VACCINES FROM 

STATE/LOCAL HEALTH 

DEPT?

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Added in 2006 due to a change in the 

IHQ. 

VFC_PRO 

PARTICIPATION OF 

CHILD'S PROVIDERS IN 

VACCINES FOR 

CHILDREN PROGRAM

Y Y Question was not asked starting in 

2006.

VRC1_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

VARICELLA-CONTAINING 

SHOT #1

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

VRC2_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

VARICELLA-CONTAINING 

SHOT #2

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

VRC3_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

VARICELLA-CONTAINING 

SHOT #3

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

VRC4_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

VARICELLA-CONTAINING 

SHOT #4

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

VRC5_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

VARICELLA-CONTAINING 

SHOT #5

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

VRC6_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

VARICELLA-CONTAINING 

SHOT #6

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

VRC7_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

VARICELLA-CONTAINING 

SHOT #7

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

VRC8_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

VARICELLA-CONTAINING 

SHOT #8

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

VRC9_AGE 

AGE IN MONTHS OF 

PROV-REPTD 

VARICELLA-CONTAINING 

SHOT #9

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

WGT 

NEW WEIGHT FOR 

CHILDREN WITH 

ADEQUATE PROVIDER 

DATA AND 

UNVACCINATED 

CHILDREN

Y Replaced by PROVWT starting in 

2005.

WGT_RDD RDD CHILD INTERVIEW 

WEIGHT Y Replaced by RDDWT starting in 2005.

XDTPTY1 

DT-CONTAINING 

VACCINATION #1 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XDTPTY2 

DT-CONTAINING 

VACCINATION #2 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XDTPTY3 

DT-CONTAINING 

VACCINATION #3 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XDTPTY4 

DT-CONTAINING 

VACCINATION #4 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XDTPTY5 

DT-CONTAINING 

VACCINATION #5 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XDTPTY6 

DT-CONTAINING 

VACCINATION #6 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

XDTPTY7 

DT-CONTAINING 

VACCINATION #7 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XDTPTY8 

DT-CONTAINING 

VACCINATION #8 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XDTPTY9 

DT-CONTAINING 

VACCINATION #9 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

XFLUTY1 

SEASONAL FLUCONTAINING 

VACCINATION #1 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2008, influenza type boxes 

were added to the IHQ shot grid.

XFLUTY2 

SEASONAL FLUCONTAINING 

VACCINATION #2 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2008, influenza type boxes 

were added to the IHQ shot grid.

XFLUTY3 

SEASONAL FLUCONTAINING 

VACCINATION #3 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2008, influenza type boxes 

were added to the IHQ shot grid.

XFLUTY4 

SEASONAL FLUCONTAINING 

VACCINATION #4 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2008, influenza type boxes 

were added to the IHQ shot grid.

XFLUTY5 

SEASONAL FLUCONTAINING 

VACCINATION #5 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2008, influenza type boxes 

were added to the IHQ shot grid.

XFLUTY6 

SEASONAL FLUCONTAINING 

VACCINATION #6 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2008, influenza type boxes 

were added to the IHQ shot grid.

XFLUTY7 

SEASONAL FLUCONTAINING 

VACCINATION #7 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2008, influenza type boxes 

were added to the IHQ shot grid.

XFLUTY8 

SEASONAL FLUCONTAINING 

VACCINATION #8 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2008, influenza type boxes 

were added to the IHQ shot grid.

XFLUTY9 

SEASONAL FLUCONTAINING 

VACCINATION #9 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2008, influenza type boxes 

were added to the IHQ shot grid.
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Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

XH1NTY1 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATION #1 TYPE 

CODE 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

XH1NTY2 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATION #2 TYPE 

CODE 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

XH1NTY3 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATION #3 TYPE 

CODE 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

XH1NTY4 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATION #4 TYPE 

CODE 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

XH1NTY5 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATION #5 TYPE 

CODE 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

XH1NTY6 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATION #6 TYPE 

CODE 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

XH1NTY7 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATION #7 TYPE 

CODE 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

XH1NTY8 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATION #8 TYPE 

CODE 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.

XH1NTY9 

MONOVALENT 2009 H1N1 

INFLUENZA 

VACCINATION #9 TYPE 

CODE 

Y Y Y 

H1N1 influenza added to the IHQ 

shotgrid starting in late 2009, and 

introduced in the PUF in 2010. 

Removed from the IHQ and the PUF in 

2013.
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193

Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

XHEPTY1

HEPATITIS BCONTAINING 

VACCINATION #1 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XHEPTY2 

HEPATITIS BCONTAINING 

VACCINATION #2 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XHEPTY3 

HEPATITIS BCONTAINING 

VACCINATION #3 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XHEPTY4 

HEPATITIS BCONTAINING 

VACCINATION #4 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XHEPTY5 

HEPATITIS BCONTAINING 

VACCINATION #5 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XHEPTY6 

HEPATITIS BCONTAINING 

VACCINATION #6 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XHEPTY7 

HEPATITIS BCONTAINING 

VACCINATION #7 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XHEPTY8 

HEPATITIS BCONTAINING 

VACCINATION #8 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XHEPTY9 

HEPATITIS BCONTAINING 

VACCINATION #9 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

XHIBTY1 

HIB-CONTAINING 

VACCINATION #1 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XHIBTY2 

HIB-CONTAINING 

VACCINATION #2 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XHIBTY3 

HIB-CONTAINING 

VACCINATION #3 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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194

Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

XHIBTY4 

HIB-CONTAINING 

VACCINATION #4 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XHIBTY5 

HIB-CONTAINING 

VACCINATION #5 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XHIBTY6 

HIB-CONTAINING 

VACCINATION #6 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XHIBTY7 

HIB-CONTAINING 

VACCINATION #7 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XHIBTY8 

HIB-CONTAINING 

VACCINATION #8 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XHIBTY9 

HIB-CONTAINING 

VACCINATION #9 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

XMMRTY1

MEASLES-CONTAINING 

VACCINATION #1 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XMMRTY2

MEASLES-CONTAINING 

VACCINATION #2 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XMMRTY3

MEASLES-CONTAINING 

VACCINATION #3 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XMMRTY4

MEASLES-CONTAINING 

VACCINATION #4 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XMMRTY5

MEASLES-CONTAINING 

VACCINATION #5 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

XMMRTY6

MEASLES-CONTAINING 

VACCINATION #6 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

XMMRTY7

MEASLES-CONTAINING 

VACCINATION #7 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

XMMRTY8

MEASLES-CONTAINING 

VACCINATION #8 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

XMMRTY9

MEASLES-CONTAINING 

VACCINATION #9 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.
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195

Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

XPCVTY1 

PNEUMOCOCCALCONTAINING 

VACCINATION #1 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XPCVTY2 

PNEUMOCOCCALCONTAINING 

VACCINATION #2 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XPCVTY3 

PNEUMOCOCCALCONTAINING 

VACCINATION #3 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XPCVTY4 

PNEUMOCOCCALCONTAINING 

VACCINATION #4 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XPCVTY5 

PNEUMOCOCCALCONTAINING 

VACCINATION #5 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XPCVTY6 

PNEUMOCOCCALCONTAINING 

VACCINATION #6 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XPCVTY7 

PNEUMOCOCCALCONTAINING 

VACCINATION #7 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XPCVTY8 

PNEUMOCOCCALCONTAINING 

VACCINATION #8 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XPCVTY9 

PNEUMOCOCCALCONTAINING 

VACCINATION #9 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

XPOLTY1 

POLIO-CONTAINING 

VACCINATION #1 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XPOLTY2 

POLIO-CONTAINING 

VACCINATION #2 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XPOLTY3 

POLIO-CONTAINING 

VACCINATION #3 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 
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196

Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

XPOLTY4 

POLIO-CONTAINING 

VACCINATION #4 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XPOLTY5 

POLIO-CONTAINING 

VACCINATION #5 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XPOLTY6 

POLIO-CONTAINING 

VACCINATION #6 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XPOLTY7 

POLIO-CONTAINING 

VACCINATION #7 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XPOLTY8 

POLIO-CONTAINING 

VACCINATION #8 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

XPOLTY9 

POLIO-CONTAINING 

VACCINATION #9 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Starting in 2005, nine shot variables are 

included for each vaccine category.

XROTTY1 

ROTAVIRUS-CONTAINING 

VACCINATION #1 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Rotavirus vaccination types were added 

to the IHQ starting 2009.

XROTTY2 

ROTAVIRUS-CONTAINING 

VACCINATION #2 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Rotavirus vaccination types were added 

to the IHQ starting 2009.

XROTTY3 

ROTAVIRUS-CONTAINING 

VACCINATION #3 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Rotavirus vaccination types were added 

to the IHQ starting 2009.

XROTTY4 

ROTAVIRUS-CONTAINING 

VACCINATION #4 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Rotavirus vaccination types were added 

to the IHQ starting 2009.

XROTTY5 

ROTAVIRUS-CONTAINING 

VACCINATION #5 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Rotavirus vaccination types were added 

to the IHQ starting 2009.

XROTTY6 

ROTAVIRUS-CONTAINING 

VACCINATION #6 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Rotavirus vaccination types were added 

to the IHQ starting 2009.

XROTTY7 

ROTAVIRUS-CONTAINING 

VACCINATION #7 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Rotavirus vaccination types were added 

to the IHQ starting 2009.

XROTTY8 

ROTAVIRUS-CONTAINING 

VACCINATION #8 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Rotavirus vaccination types were added 

to the IHQ starting 2009.

XROTTY9 

ROTAVIRUS-CONTAINING 

VACCINATION #9 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Rotavirus vaccination types were added 

to the IHQ starting 2009.
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197

Variable Name Variable Label† 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Notes§

XVRCTY1 

VARICELLA-CONTAINING 

VACCINATION #1 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Varicella vaccination types were added 

to the IHQ starting 2006.

XVRCTY2 

VARICELLA-CONTAINING 

VACCINATION #2 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Varicella vaccination types were added 

to the IHQ starting 2006.

XVRCTY3 

VARICELLA-CONTAINING 

VACCINATION #3 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Varicella vaccination types were added 

to the IHQ starting 2006.

XVRCTY4 

VARICELLA-CONTAINING 

VACCINATION #4 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Varicella vaccination types were added 

to the IHQ starting 2006.

XVRCTY5 

VARICELLA-CONTAINING 

VACCINATION #5 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Varicella vaccination types were added 

to the IHQ starting 2006.

XVRCTY6 

VARICELLA-CONTAINING 

VACCINATION #6 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Varicella vaccination types were added 

to the IHQ starting 2006.

XVRCTY7 

VARICELLA-CONTAINING 

VACCINATION #7 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Varicella vaccination types were added 

to the IHQ starting 2006.

XVRCTY8 

VARICELLA-CONTAINING 

VACCINATION #8 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Varicella vaccination types were added 

to the IHQ starting 2006.

XVRCTY9 

VARICELLA-CONTAINING 

VACCINATION #9 TYPE 

CODE 

Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Varicella vaccination types were added 

to the IHQ starting 2006.

YEAR YEAR OF INTERVIEW Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 

* For a list of variables that appeared in one or more (but not all) NIS-Child public-use data files from 1995-2004, see "Alphabetical Listing of Variables that are Not Available in All Public-Use Data 

Files, National Immunization Survey, 1995-2004": http://www.cdc.gov/nchs/data/nis/pufvariables1995to2004.pdf

† If the variable appeared in the 2021 NIS-Child public-use data file, then the 2021 label is given; otherwise the label from the most recent NIS-Child public-use data file in which the variable 

appeared is given.

§ Starting in 2005, a code of 77 is used for "Don't Know" responses and a code of 99 is used for "Refused" responses.
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Appendix F

198

Appendix F: Summary Tables 

Table F.1: Estimated Population Totals and Sample Sizes of Children 19-35 Months of Age by 

State and Estimation Area, National Immunization Survey - Child, 2021 

State/Estimation Area ESTIAP21

Estimated 

Population 

Total of 

Children

Number of 

Children

with 

Complete 

Household 

Interviews

Number of 

Children 

with 

Adequate 

Provider 

Data

Percent of 

Children with 

Adequate 

Provider Data

U.S. National* 5,455,449 34,863 17,967 51.5

Alabama 20 82,191 510 254 49.8

Alaska 74 13,038 515 285 55.3

Arizona 66 118,526 446 234 52.5

Arkansas 46 51,341 780 413 52.9

California 68 651,666 1,188 553 46.5

Colorado 60 90,812 475 258 54.3

Connecticut 1 50,329 755 409 54.2

Delaware 13 14,583 412 192 46.6

District of Columbia 12 11,981 712 334 46.9

Florida 22 326,313 590 291 49.3

Georgia 25 185,777 558 266 47.7

Hawaii 72 23,488 523 271 51.8

Idaho 75 32,273 630 364 57.8

Illinois 201,225 996 530 53.2

 IL-City of Chicago 35 46,180 266 141 53.0

 IL-Rest of State 34 155,045 730 389 53.3

Indiana 36 116,938 414 216 52.2

Iowa 56 53,493 440 228 51.8

Kansas 57 50,896 627 348 55.5

Kentucky 27 76,699 526 242 46.0

Louisiana 47 84,472 759 380 50.1

Maine 4 17,407 434 235 54.1

Maryland 14 103,835 1,392 730 52.4

Massachusetts 2 101,403 590 335 56.8

Michigan 38 155,594 683 343 50.2

Minnesota 40 97,529 536 260 48.5

Mississippi 28 51,707 764 314 41.1

Missouri 58 103,279 730 398 54.5

Montana 61 17,235 458 225 49.1

Nebraska 59 35,099 447 262 58.6

Nevada 73 52,823 744 386 51.9

New Hampshire 5 17,952 499 248 49.7

New Jersey 8 147,525 615 283 46.0

New Mexico 49 31,259 648 386 59.6
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199

State/Estimation Area ESTIAP21

Estimated 

Population 

Total of 

Children

Number of 

Children

with 

Complete 

Household 

Interviews

Number of 

Children 

with 

Adequate 

Provider 

Data

Percent of 

Children with 

Adequate 

Provider Data

New York 311,593 1,436 690 48.1

 NY-City of New York 11 149,895 909 437 48.1

 NY-Rest of State 10 161,698 527 253 48.0

North Carolina 29 172,331 550 272 49.5

North Dakota 62 14,299 596 280 47.0

Ohio 41 193,494 866 442 51.0

Oklahoma 50 71,222 427 192 45.0

Oregon 76 61,325 498 284 57.0

Pennsylvania 195,581 1,368 677 49.5

 PA-Philadelphia County 17 30,063 532 243 45.7

 PA-Rest of State 16 165,518 836 434 51.9

Rhode Island 6 14,791 473 247 52.2

South Carolina 30 83,984 520 235 45.2

South Dakota 63 16,058 581 327 56.3

Tennessee 31 119,781 783 408 52.1

Texas 560,425 2,060 1,038 50.4

 TX-Bexar County 55 38,987 486 233 47.9

 TX-City of Houston 54 71,070 446 216 48.4

 TX-Rest of State 51 450,368 1,128 589 52.2

Utah 64 67,708 609 384 63.1

Vermont 7 7,849 557 323 58.0

Virginia 18 143,589 976 520 53.3

Washington 77 126,253 803 478 59.5

West Virginia 19 26,023 419 210 50.1

Wisconsin 44 91,685 487 245 50.3

Wyoming 65 8,773 458 242 52.8

Puerto Rico 106 27,190 1,132 352 31.1

*Excludes U.S. territories. 
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200

Table F.2: Estimated Population Totals and Sample Sizes for Age Group by Maternal Education, 

National Immunization Survey - Child, 2021 

Age Group 

in Months Maternal Education

Children with 

Completed 

Household 

Interviews*

Unweighted 

Completes

Children with 

Completed 

Household 

Interviews*

Weighted 

Completes†

Children with 

Adequate 

Provider 

Data*

Unweighted 

Completes

Children with 

Adequate 

Provider 

Data*

Weighted 

Completes§

19-23 <12 Years 460 144,824 227 147,167

19-23 12 Years 1,777 495,368 800 472,592

19-23 >12, Non College Graduate 2,418 346,350 1,205 350,652

19-23 College Graduate 5,261 660,420 2,816 676,552

24-29 <12 Years 578 173,493 271 174,644

24-29 12 Years 1,766 512,369 838 509,140

24-29 >12, Non College Graduate 2,631 399,585 1,271 391,742

24-29 College Graduate 5,384 753,841 2,933 763,762

30-35 <12 Years 821 198,244 414 200,310

30-35 12 Years 2,460 579,463 1,160 599,950

30-35 >12, Non College Graduate 3,609 415,028 1,836 424,129

30-35 College Graduate 7,698 776,463 4,196 744,808

Total 34,863 5,455,449 17,967 5,455,449

* Excludes U.S. territories. 

† Weighted by RDDWT_C. 

§ Weighted by PROVWT_C. 
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201

Table F.3: Estimated Population Totals and Sample Sizes for Age Group by Poverty Status, 

National Immunization Survey - Child, 2021 

Age Group in 

Months Poverty Status

Children 

with 

Completed 

Household 

Interviews*

Unweighted 

Completes

Children 

with 

Completed 

Household 

Interviews*

Weighted 

Completes†

Children

with 

Adequate 

Provider 

Data*

Unweighted 

Completes

Children 

with 

Adequate 

Provider 

Data*

Weighted 

Completes§

19-23 Months Above poverty, > $75K 4,870 648,866 2,648 675,523

19-23 Months Above poverty, <= $75K 2,923 521,588 1,444 514,880

19-23 Months Below poverty 1,552 368,733 800 348,638

19-23 Months Unknown 571 107,775 156 107,922

24-29 Months Above poverty, > $75K 5,093 728,057 2,760 756,807

24-29 Months Above poverty, <= $75K 3,009 556,306 1,553 571,662

24-29 Months Below poverty 1,667 417,319 834 406,408

24-29 Months Unknown 590 137,606 166 104,412

30-35 Months Above poverty, > $75K 7,098 756,494 3,911 741,297

30-35 Months Above poverty, <= $75K 4,302 587,641 2,225 594,848

30-35 Months Below poverty 2,355 490,107 1,241 521,395

30-35 Months Unknown 833 134,957 229 111,659

Total 34,863 5,455,449 17,967 5,455,449

* Excludes U.S. territories. 

† Weighted by RDDWT_C. 

§ Weighted by PROVWT_C. 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Appendix F

202

Table F.4: Estimated Population Totals and Sample Sizes for Race/Ethnicity by Poverty Status, 

National Immunization Survey - Child, 2021 

Race/Ethnicity† Poverty Status

Children with 

Completed 

Household 

Interviews*

Unweighted 

Completes

Children with 

Completed 

Household 

Interviews*

Weighted 

Completes§

Children with 

Adequate 

Provider 

Data*

Unweighted 

Completes

Children with 

Adequate 

Provider 

Data*

Weighted 

Completes¶

Hispanic Above poverty, > $75K 2,087 375,571 1,086 368,973

Hispanic Above poverty, <= $75K 2,198 504,001 1,114 508,640

Hispanic Below poverty 1,829 507,924 994 503,363

Hispanic Unknown 463 124,629 158 130,314

Non-Hispanic White Only Above poverty, > $75K 11,193 1,252,150 6,335 1,294,893

Non-Hispanic White Only Above poverty, <= $75K 5,221 692,388 2,750 692,347

Non-Hispanic White Only Below poverty 1,809 329,160 973 332,725

Non-Hispanic White Only Unknown 929 145,044 242 107,253

Non-Hispanic Black Only Above poverty, > $75K 1,010 151,293 386 147,309

Non-Hispanic Black Only Above poverty, <= $75K 1,293 248,851 559 255,336

Non-Hispanic Black Only Below poverty 1,059 278,980 471 283,775

Non-Hispanic Black Only Unknown 243 49,849 46 28,912

Non-Hispanic Other & 

Multiple Races Above poverty, > $75K 2,771 354,403 1,512 362,451

Non-Hispanic Other & 

Multiple Races Above poverty, <= $75K 1,522 220,294 799 225,067

Non-Hispanic Other & 

Multiple Races Below poverty 877 160,094 437 156,577

Non-Hispanic Other & 

Multiple Races Unknown 359 60,817 105 57,513

Total 34,863 5,455,449 17,967 5,455,449

* Excludes U.S. territories.

† Race/Ethnicity is self-reported and mutually exclusive.

§ Weighted by RDDWT_C. 

¶ Weighted by PROVWT_C. 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Appendix F

203

Table F.5: Estimated Population Totals and Sample Sizes for Age Group by Race/Ethnicity, 

National Immunization Survey - Child, 2021 

Age Group in 

Months Race/Ethnicity of Child†

Children with 

Completed 

Household 

Interviews*

Unweighted 

Completes

Children with 

Completed 

Household 

Interviews*

Weighted 

Completes§

Children with 

Adequate 

Provider 

Data*

Unweighted 

Completes

Children with 

Adequate 

Provider 

Data*

Weighted 

Completes¶

19-23 Months Hispanic 1,786 445,196 898 447,795

19-23 Months Non-Hispanic White Only 5,551 752,903 2,950 774,213

19-23 Months Non-Hispanic Black Only 965 207,422 375 193,617

19-23 Months Non-Hispanic Other & Multiple 

Races 1,614 241,441 825 231,338

24-29 Months Hispanic 2,041 508,886 1,054 498,428

24-29 Months Non-Hispanic White Only 5,575 814,204 2,969 810,314

24-29 Months Non-Hispanic Black Only 1,139 248,609 470 251,070

24-29 Months Non-Hispanic Other & Multiple 

Races 1,604 267,589 820 279,476

30-35 Months Hispanic 2,750 558,043 1,400 565,068

30-35 Months Non-Hispanic White Only 8,026 851,635 4,381 842,691

30-35 Months Non-Hispanic Black Only 1,501 272,943 617 270,646

30-35 Months Non-Hispanic Other & Multiple 

Races 2,311 286,578 1,208 290,793

Total 34,863 5,455,449 17,967 5,455,449

* Excludes U.S. territories.

† Race/Ethnicity is self-reported and mutually exclusive.

§ Weighted by RDDWT_C. 

¶ Weighted by PROVWT_C. 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File Appendix F

204

Table F.6: Estimated Population Totals and Sample Sizes for Age Group by Sex, National 

Immunization Survey - Child, 2021 

Age Group in 

Months Sex 

Children with 

Completed 

Household 

Interviews*

Unweighted 

Completes

Children with 

Completed 

Household 

Interviews*

Weighted 

Completes†

Children with 

Adequate 

Provider 

Data*

Unweighted 

Completes

Children with 

Adequate 

Provider 

Data*

Weighted 

Completes§

19-23 Months Male 5,017 833,965 2,556 847,336

19-23 Months Female 4,899 812,998 2,492 799,627

 

24-29 Months Male 5,306 947,849 2,750 945,023

24-29 Months Female 5,053 891,439 2,563 894,266

 

30-35 Months Male 7,465 1,007,865 3,878 997,323

30-35 Months Female 7,123 961,333 3,728 971,874

Total 34,863 5,455,449 17,967 5,455,449

* Excludes U.S. territories. 

† Weighted by RDDWT_C. 

§ Weighted by PROVWT_C. 
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205

Table F.7: Estimated Vaccination Coverage* with Individual Vaccines and Selected Vaccination Series Among Children 19-35 Months 

of Age by State and Estimation Area, National Immunization Survey - Child, 2021†

 ≥4 DTaP§ ≥3 Polio¶ ≥1 MMR** Hib-FS†† ≥3 HepB¶¶ HepB Birth 

Dose ≥1 HepA ≥1 Var*** ≥4 PCV††† Rotavirus 4:3:1:3*:3:1:4§§§

U.S. National¶¶¶ 84.4 ± 1.1 93.8 ± 0.7 92.1 ± 0.8 80.6 ± 1.2 93.2 ± 0.7 80.7 ± 1.2 89.6 ± 0.9 91.6 ± 0.9 84.6 ± 1.1 78.7 ± 1.2 72.1 ± 1.4

Alabama 84.4 ± 6.0 95.0 ± 3.7 96.3 ± 3.0 81.6 ± 6.7 95.0 ± 3.6 81.3 ± 6.6 92.9 ± 4.1 95.3 ± 3.6 84.9 ± 6.3 78.9 ± 6.8 70.2 ± 7.7

Alaska 78.6 ± 5.9 88.6 ± 4.7 87.1 ± 5.0 74.8 ± 6.5 88.8 ± 4.8 68.2 ± 6.9 83.5 ± 5.6 83.7 ± 5.4 72.1 ± 6.7 66.5 ± 7.1 61.3 ± 7.2

Arizona 77.8 ± 7.9 90.3 ± 6.0 91.3 ± 5.5 71.3 ± 8.0 88.8 ± 6.0 80.0 ± 6.9 88.2 ± 6.5 91.5 ± 5.6 77.8 ± 8.0 76.8 ± 7.7 62.2 ± 8.4

Arkansas 77.4 ± 5.7 91.3 ± 3.7 89.7 ± 4.1 78.5 ± 5.6 91.3 ± 3.7 77.9 ± 5.6 87.7 ± 4.3 90.5 ± 4.0 77.4 ± 5.8 77.9 ± 5.4 68.3 ± 6.3

California 84.1 ± 5.1 93.7 ± 3.4 91.7 ± 3.9 78.1 ± 5.8 93.0 ± 3.3 71.9 ± 6.0 90.1 ± 4.1 88.3 ± 4.6 84.8 ± 5.0 79.0 ± 5.5 69.1 ± 6.3

Colorado 81.3 ± 7.4 94.8 ± 4.1 90.7 ± 5.7 81.9 ± 7.6 94.4 ± 3.2 84.4 ± 5.8 87.6 ± 6.5 89.6 ± 6.1 86.4 ± 6.7 85.1 ± 6.7 71.1 ± 8.5

Connecticut 91.1 ± 3.8 94.5 ± 3.1 94.9 ± 2.9 91.8 ± 3.4 94.9 ± 3.0 86.6 ± 3.9 93.5 ± 3.4 95.6 ± 2.8 92.3 ± 3.4 83.2 ± 4.7 84.0 ± 4.5

Delaware 88.4 ± 5.4 96.8 ± 2.1 94.7 ± 3.3 84.7 ± 6.3 94.3 ± 3.2 80.7 ± 6.9 92.7 ± 3.9 93.6 ± 3.9 86.7 ± 5.6 76.6 ± 7.0 76.3 ± 7.3

Dist. of Columbia 81.6 ± 6.2 92.6 ± 3.6 88.9 ± 4.4 81.2 ± 5.6 90.5 ± 4.1 77.1 ± 6.6 92.2 ± 3.5 89.1 ± 4.4 84.1 ± 5.1 79.0 ± 6.0 71.5 ± 7.0

Florida 85.9 ± 7.2 91.0 ± 5.8 89.7 ± 6.2 83.8 ± 7.8 92.1 ± 5.1 73.7 ± 8.8 84.1 ± 7.6 89.6 ± 6.2 80.7 ± 8.4 71.6 ± 9.3 73.3 ± 9.4

Georgia 74.2 ± 8.7 92.8 ± 4.8 90.5 ± 5.8 72.3 ± 8.6 93.2 ± 4.2 84.3 ± 6.2 89.8 ± 6.0 90.5 ± 5.8 75.9 ± 8.5 74.0 ± 8.1 63.3 ± 9.1

Hawaii 78.8 ± 6.6 90.9 ± 4.2 88.1 ± 5.1 78.2 ± 6.7 90.1 ± 4.3 88.2 ± 4.1 86.5 ± 5.2 89.0 ± 4.6 81.0 ± 6.4 84.4 ± 4.8 72.2 ± 7.0

Idaho 86.0 ± 4.8 93.9 ± 3.3 92.5 ± 3.7 86.4 ± 4.5 94.8 ± 3.1 80.6 ± 5.4 93.0 ± 3.6 92.2 ± 3.7 87.3 ± 4.6 78.8 ± 5.7 75.9 ± 5.8

Illinois 85.7 ± 4.1 93.1 ± 3.2 90.7 ± 3.5 81.3 ± 4.4 92.7 ± 3.1 81.4 ± 4.4 87.6 ± 3.9 91.3 ± 3.4 82.9 ± 4.6 80.2 ± 4.9 73.2 ± 5.1

IL-City of Chicago 84.6 ± 8.4 95.7 ± 4.9 90.5 ± 6.6 81.5 ± 8.6 93.1 ± 6.3 80.7 ± 8.4 91.3 ± 6.3 93.7 ± 5.9 81.7 ± 9.5 83.4 ± 8.6 69.4 ± 10.5

IL-Rest of State 86.1 ± 4.7 92.3 ± 3.8 90.8 ± 4.1 81.2 ± 5.1 92.5 ± 3.6 81.5 ± 5.1 86.5 ± 4.7 90.6 ± 4.1 83.3 ± 5.3 79.2 ± 5.8 74.3 ± 5.8

Indiana 82.6 ± 6.2 91.0 ± 5.1 87.5 ± 5.8 81.4 ± 6.6 92.5 ± 4.5 84.8 ± 5.6 92.5 ± 4.8 90.2 ± 5.2 84.4 ± 6.2 78.6 ± 6.9 70.7 ± 7.8

Iowa 91.6 ± 5.8 96.5 ± 3.8 96.5 ± 3.8 92.3 ± 4.8 96.6 ± 3.4 85.6 ± 5.7 92.7 ± 5.1 95.3 ± 4.0 93.3 ± 5.2 87.5 ± 6.4 87.9 ± 6.1

Kansas 80.1 ± 6.5 90.6 ± 5.0 90.5 ± 5.0 75.8 ± 6.6 94.2 ± 3.7 81.4 ± 5.9 86.9 ± 5.7 90.6 ± 4.9 83.5 ± 6.1 78.5 ± 6.1 67.1 ± 7.1

Kentucky 83.9 ± 5.6 93.7 ± 4.1 92.5 ± 3.9 80.9 ± 6.0 94.6 ± 3.4 83.8 ± 5.8 91.4 ± 4.2 92.2 ± 4.4 83.8 ± 5.9 78.8 ± 6.2 75.2 ± 6.7

Louisiana 73.9 ± 6.8 93.8 ± 3.6 91.5 ± 4.4 71.5 ± 6.9 90.5 ± 4.4 69.7 ± 6.7 87.2 ± 4.9 90.7 ± 4.4 74.7 ± 6.6 67.2 ± 7.1 62.0 ± 7.2

Maine 88.1 ± 5.3 97.5 ± 2.9 94.6 ± 3.5 86.1 ± 5.6 96.1 ± 2.6 83.1 ± 5.4 94.0 ± 3.7 94.7 ± 3.2 87.9 ± 5.0 75.9 ± 6.5 78.5 ± 6.5

Maryland 89.9 ± 3.1 97.3 ± 1.6 95.4 ± 1.9 87.1 ± 3.2 95.2 ± 2.2 82.1 ± 4.0 91.9 ± 2.9 95.1 ± 2.0 89.7 ± 3.0 84.6 ± 3.9 80.6 ± 3.9

Massachusetts 91.7 ± 4.1 96.5 ± 3.1 96.4 ± 2.5 91.3 ± 4.4 97.6 ± 1.9 86.8 ± 5.5 96.4 ± 2.4 96.5 ± 2.5 93.4 ± 3.8 87.2 ± 5.4 85.4 ± 5.5

Michigan 86.7 ± 5.3 94.2 ± 3.7 93.1 ± 3.8 78.6 ± 6.3 94.7 ± 3.1 85.6 ± 5.2 94.0 ± 3.3 93.5 ± 3.4 88.8 ± 4.4 74.2 ± 6.7 72.3 ± 6.8

Minnesota 84.5 ± 6.9 95.2 ± 3.9 92.7 ± 4.9 81.1 ± 7.3 96.0 ± 2.9 81.2 ± 7.5 92.5 ± 4.9 91.7 ± 5.4 85.2 ± 7.0 88.4 ± 6.0 68.3 ± 9.0

Mississippi 78.0 ± 7.6 88.5 ± 5.8 91.6 ± 4.6 77.1 ± 7.3 90.4 ± 5.4 79.8 ± 7.4 69.2 ± 7.9 90.5 ± 5.2 81.3 ± 6.9 64.2 ± 8.7 67.8 ± 8.2

Missouri 79.5 ± 6.0 87.8 ± 5.0 87.2 ± 5.2 74.4 ± 6.3 88.5 ± 5.0 81.2 ± 5.4 85.0 ± 5.3 86.7 ± 5.2 79.0 ± 6.2 73.7 ± 6.4 70.1 ± 6.5

Montana 83.8 ± 5.8 95.6 ± 3.0 92.6 ± 4.2 78.2 ± 6.4 91.4 ± 4.2 71.7 ± 7.0 86.5 ± 5.4 93.3 ± 3.9 84.8 ± 5.6 80.4 ± 6.1 69.1 ± 7.1

Nebraska 92.9 ± 4.0 98.2 ± 1.5 95.9 ± 2.8 83.5 ± 6.0 96.1 ± 2.7 83.2 ± 6.7 92.6 ± 4.2 96.6 ± 2.7 93.1 ± 4.1 84.7 ± 6.2 79.0 ± 6.6

Nevada 82.0 ± 5.3 96.0 ± 2.6 93.6 ± 3.3 78.1 ± 5.6 95.0 ± 3.2 85.9 ± 4.5 92.0 ± 3.6 93.6 ± 3.3 80.0 ± 5.5 74.7 ± 5.8 73.9 ± 5.9

New Hampshire 85.7 ± 5.3 94.9 ± 3.6 97.4 ± 1.9 84.5 ± 5.5 94.9 ± 3.4 87.9 ± 4.7 92.2 ± 3.9 96.7 ± 2.3 86.4 ± 5.6 82.7 ± 5.8 78.9 ± 6.0

New Jersey 83.1 ± 6.1 95.4 ± 3.4 91.1 ± 4.9 79.3 ± 6.9 92.8 ± 4.1 78.6 ± 6.5 84.6 ± 5.8 89.9 ± 4.9 81.7 ± 6.6 73.8 ± 7.6 66.0 ± 7.9

New Mexico 81.7 ± 5.6 93.2 ± 3.7 93.8 ± 3.5 82.9 ± 5.5 92.8 ± 3.6 76.5 ± 5.6 91.3 ± 4.0 92.1 ± 3.9 82.9 ± 5.6 78.7 ± 6.0 72.3 ± 6.3

New York 85.4 ± 4.0 93.5 ± 2.9 93.5 ± 2.7 79.2 ± 4.8 92.4 ± 3.0 78.6 ± 4.9 86.0 ± 4.0 92.7 ± 3.0 80.7 ± 4.7 79.6 ± 4.7 69.2 ± 5.3

NY-City of New York 82.2 ± 5.0 91.9 ± 3.6 92.5 ± 3.3 78.8 ± 5.4 89.3 ± 4.2 78.8 ± 5.2 85.9 ± 4.5 92.5 ± 3.2 79.6 ± 5.2 77.3 ± 5.5 68.1 ± 5.9

NY-Rest of State 88.3 ± 6.2 95.1 ± 4.4 94.4 ± 4.3 79.7 ± 7.7 95.2 ± 4.3 78.3 ± 8.2 86.1 ± 6.4 93.0 ± 4.9 81.7 ± 7.6 81.6 ± 7.5 70.2 ± 8.6
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206

 ≥4 DTaP§ ≥3 Polio¶ ≥1 MMR** Hib-FS†† ≥3 HepB¶¶ HepB Birth 

Dose ≥1 HepA ≥1 Var*** ≥4 PCV††† Rotavirus 4:3:1:3*:3:1:4§§§

North Carolina 89.9 ± 5.6 94.7 ± 3.9 96.3 ± 3.2 88.5 ± 5.6 93.2 ± 4.7 84.4 ± 6.8 92.5 ± 5.0 96.3 ± 3.2 90.6 ± 5.5 78.4 ± 7.9 79.5 ± 7.7

North Dakota 86.9 ± 5.3 96.0 ± 3.1 93.5 ± 4.0 86.7 ± 5.6 95.2 ± 3.3 84.8 ± 6.5 89.3 ± 5.5 91.1 ± 4.8 88.9 ± 5.1 83.6 ± 6.5 81.3 ± 6.3

Ohio 86.7 ± 5.0 95.0 ± 2.9 94.2 ± 3.2 78.1 ± 5.9 93.2 ± 3.4 83.0 ± 5.0 90.4 ± 3.8 94.9 ± 2.8 84.2 ± 5.5 75.7 ± 6.1 72.0 ± 6.2

Oklahoma 82.0 ± 6.8 93.8 ± 4.2 90.3 ± 5.1 80.9 ± 6.8 94.5 ± 3.7 79.7 ± 6.5 90.2 ± 4.7 90.4 ± 4.9 79.9 ± 7.3 79.0 ± 7.7 71.9 ± 7.9

Oregon 81.6 ± 6.2 95.0 ± 3.1 92.2 ± 4.2 85.0 ± 5.5 93.9 ± 3.8 84.5 ± 5.5 90.9 ± 4.4 92.2 ± 4.0 87.0 ± 4.9 78.1 ± 6.8 74.8 ± 6.7

Pennsylvania 84.4 ± 4.8 95.1 ± 2.8 95.6 ± 2.6 82.2 ± 5.1 96.1 ± 2.5 89.2 ± 3.5 93.2 ± 3.5 95.2 ± 3.0 89.3 ± 3.7 80.4 ± 5.7 75.7 ± 5.6

PA-Philadelphia County 79.3 ± 6.8 92.9 ± 4.4 93.0 ± 4.0 78.5 ± 6.7 91.8 ± 5.0 84.7 ± 5.7 93.2 ± 3.9 93.7 ± 3.9 81.6 ± 6.4 76.8 ± 6.8 70.8 ± 7.5

PA-Rest of State 85.3 ± 5.5 95.5 ± 3.3 96.1 ± 3.0 82.8 ± 5.9 96.8 ± 2.9 90.0 ± 4.0 93.2 ± 4.1 95.5 ± 3.5 90.7 ± 4.2 81.0 ± 6.6 76.6 ± 6.4

Rhode Island 92.8 ± 4.1 99.7 ± 0.5 97.6 ± 2.4 91.1 ± 4.5 99.5 ± 0.6 74.4 ± 7.0 96.9 ± 3.0 96.8 ± 2.9 94.0 ± 3.8 90.9 ± 4.5 80.0 ± 6.3

South Carolina 81.7 ± 6.4 95.2 ± 3.8 93.1 ± 4.3 76.6 ± 6.8 93.1 ± 4.5 82.3 ± 5.8 91.0 ± 4.8 92.6 ± 4.1 84.9 ± 6.1 79.0 ± 6.4 68.5 ± 7.2

South Dakota 78.3 ± 5.9 94.0 ± 3.5 92.6 ± 3.7 72.8 ± 6.2 93.4 ± 3.6 86.1 ± 4.8 87.6 ± 4.8 90.6 ± 4.2 83.1 ± 5.3 80.3 ± 5.7 66.8 ± 6.5

Tennessee 86.2 ± 4.9 91.7 ± 4.0 92.7 ± 3.6 78.4 ± 5.8 92.7 ± 3.6 70.8 ± 6.2 92.3 ± 3.9 93.1 ± 3.5 87.7 ± 4.4 74.7 ± 6.0 69.7 ± 6.4

Texas 84.5 ± 3.4 94.5 ± 1.8 89.5 ± 2.9 80.2 ± 3.9 91.0 ± 2.6 85.2 ± 3.2 90.3 ± 2.7 90.3 ± 2.7 86.8 ± 3.1 82.4 ± 3.4 73.4 ± 4.2

TX-Bexar County 84.5 ± 5.7 95.1 ± 3.5 90.2 ± 4.8 82.6 ± 6.0 93.9 ± 3.3 82.1 ± 6.0 91.0 ± 4.4 92.6 ± 3.9 86.7 ± 5.6 78.3 ± 6.5 72.7 ± 7.0

TX-City of Houston 85.5 ± 5.9 94.6 ± 3.8 92.9 ± 4.6 87.2 ± 5.6 91.7 ± 5.0 82.8 ± 6.5 94.3 ± 4.4 92.3 ± 4.9 89.8 ± 5.2 85.3 ± 6.0 77.4 ± 7.3

TX-Rest of State 84.3 ± 4.1 94.5 ± 2.2 88.9 ± 3.5 78.9 ± 4.7 90.6 ± 3.2 85.8 ± 3.8 89.6 ± 3.3 89.8 ± 3.3 86.3 ± 3.8 82.3 ± 4.1 72.9 ± 5.1

Utah 89.5 ± 4.0 97.3 ± 2.1 94.8 ± 2.9 83.3 ± 5.0 96.0 ± 2.3 86.0 ± 4.9 93.3 ± 3.3 94.4 ± 2.7 90.0 ± 3.9 87.4 ± 4.2 78.9 ± 5.4

Vermont 90.8 ± 3.5 96.0 ± 2.3 95.6 ± 2.5 91.2 ± 3.4 94.2 ± 2.7 73.3 ± 5.6 90.8 ± 3.4 94.0 ± 2.9 91.4 ± 3.3 79.9 ± 5.3 82.1 ± 4.6

Virginia 91.0 ± 4.5 96.1 ± 3.2 94.5 ± 3.7 83.8 ± 5.8 97.1 ± 2.3 81.5 ± 5.9 92.5 ± 4.2 93.6 ± 3.9 89.0 ± 4.9 80.0 ± 6.4 78.6 ± 6.4

Washington 85.4 ± 4.6 95.7 ± 2.4 91.9 ± 3.4 87.4 ± 4.2 91.7 ± 3.4 83.3 ± 4.5 90.7 ± 3.6 90.9 ± 3.6 85.5 ± 4.4 82.1 ± 4.9 74.7 ± 5.5

West Virginia 77.1 ± 6.4 92.3 ± 4.0 92.0 ± 4.0 71.1 ± 6.8 95.1 ± 2.8 82.6 ± 5.7 93.3 ± 3.7 91.9 ± 4.1 77.7 ± 6.2 70.3 ± 6.8 56.6 ± 7.4

Wisconsin 84.1 ± 6.5 90.4 ± 5.3 90.6 ± 5.3 80.7 ± 6.8 96.6 ± 2.5 87.7 ± 5.2 85.1 ± 6.3 88.6 ± 5.6 84.6 ± 6.4 78.7 ± 7.2 73.9 ± 7.4

Wyoming 83.4 ± 6.2 94.1 ± 3.9 93.3 ± 4.5 84.0 ± 6.2 95.1 ± 3.6 76.2 ± 7.4 85.1 ± 6.3 93.2 ± 4.5 84.2 ± 6.1 80.2 ± 6.6 75.0 ± 7.0

Puerto Rico 52.8 ± 7.9 78.8 ± 6.3 71.1 ± 7.1 50.8 ± 7.8 76.6 ± 6.6 69.8 ± 7.4 72.8 ± 7.0 73.3 ± 6.9 53.1 ± 7.8 61.7 ± 7.6 38.8 ± 7.5

Guam 70.0 ± 11.9 83.1 ± 9.9 74.8 ± 11.3 72.2 ± 11.7 79.2 ± 10.7 90.4 ± 7.9 75.5 ± 11.5 74.4 ± 11.9 64.0 ± 12.5 55.2 ± 13.0 52.6 ± 13.0

U.S. Virgin Islands 66.5 ± 11.7 84.0 ± 9.2 76.9 ± 10.8 55.0 ± 12.2 80.4 ± 10.5 62.9 ± 11.6 71.1 ± 11.4 74.5 ± 11.0 59.9 ± 12.0 39.9 ± 11.9 40.6 ± 11.8

* Estimates presented as point estimate (%) ± 95% Confidence Interval half width. Estimate=NA (Not Available) if the unweighted sample size for the denominator was < 30, or (CI half width)/Estimate 

> 0.588, or (CI half width) >10.

† Children in the 2021 NIS-Child were born between January 2018 through May 2020. Vaccination coverage estimates include only children who had adequate provider-reported immunization records. § 4 or more doses of diphtheria and tetanus toxoids and acellular pertussis vaccine adsorbed, diphtheria and tetanus toxoids and pertussis vaccine, or diphtheria and tetanus toxoids vaccine adsorbed 

(DTaP/DTP/DT). 

¶ 3 or more doses of any poliovirus vaccine.

** 1 or more doses of measles-mumps-rubella vaccine †† 4 or more doses of Haemophilus influenzae type b (Hib) vaccine of any type or 2 doses of Hib of Merck types followed by 1+ dose of Hib of any type. ¶¶ 3 or more doses of hepatitis B vaccine.

*** 1 or more doses of varicella at or after child’s first birthday, unadjusted for history of varicella illness. ††† 4 or more doses of pneumococcal conjugate vaccine (PCV). §§§ 4+ diphtheria and tetanus toxoids and acellular pertussis vaccine adsorbed, diphtheria and tetanus toxoids and pertussis vaccine, or diphtheria and tetanus toxoids vaccine adsorbed (DTaP/DTP/DT); 

3+ poliovirus vaccine; 1+ measles-containing vaccine (MCV); full series Haemophilus influenzae type b conjugate vaccine (Hib), i.e., 3 or 4 doses depending on type of vaccine received; 3+ hepatitis B 

vaccine (Hep B); 1+ varicella at or after 12 months of age; and 4+ pneumococcal conjugate vaccine (PCV).

¶¶¶ U.S. national estimates exclude U.S. territories.
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207

Appendix G: Trends in NIS-Child Response Rates and 

Vaccination Coverage Rates, 1995-2021 

Table G.1: Key Indicators* from Landline Sample Household and Provider Data Collection by 

Survey Year, National Immunization Survey - Child, 1995-2017†

Survey 

Year

Resolution 

Rate (%)

Screener 

Completion 

Rate (%)

Interview 

Completion 

Rate (%)

CASRO 

Response Rate 

(%) 

Children with 

Adequate 

Provider Data 

(%) 

1995 96.5 96.4 93.5 87.1 50.6

1996 94.3 96.8 94.0 85.8 63.4

1997 92.1 97.9 93.8 84.6 69.7

1998 90.4 97.8 93.6 82.7 67.1

1999 88.6 97.0 93.4 80.2 65.4

2000 88.1 96.0 93.1 78.7 67.4

2001 86.8 96.2 91.1 76.1 70.4

2002 84.8 96.6 90.6 74.2 67.6

2003 83.6 94.0 88.7 69.8 68.9

2004 83.8 94.8 92.0 73.1 71.0

2005 83.3 92.8 84.2 65.1 63.6

2006 83.3 90.5 85.6 64.5 70.4

2007 82.9 90.2 86.8 64.9 68.6

2008 82.3 90.3 85.1 63.2 71.0

2009 82.9 92.4 83.2 63.8 68.7

2010 83.3 91.5 83.6 63.8 71.2

2011 83.0 90.7 81.7 61.6 72.3

2012 84.1 90.7 84.6 64.5 67.9

2013 83.2 91.0 82.3 62.3 63.5

2014 82.7 92.2 82.1 62.6 63.3

2015 81.9 89.9 80.3 59.1 59.7

2016 81.6 88.4 77.2 55.7 58.6

2017 80.8 84.4 76.1 51.9 57.2

* For the definition of the key indicators see Table 1 of NIS-Child Data User’s Guide for the survey year of interest.

† Excludes U.S. territories. 
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 208

Figure G.1: Trends in Landline Sample Key Indicators from Household and Provider Data 

Collection by Survey Year, National Immunization Survey - Child, 1995-2017*

* Excludes U.S. territories. 

Figure G.1 provides a graphical representation of the data contained in Table G.1. It shows how 

selected landline sample key indicators from the household and provider data collection performed 

throughout the years, from 1995 to 2017. (The NIS utilized a single-frame cellular phone design 

beginning in 2018.) We observe that the trend in the data collection rates was downward, with the 

exception of the percentage of children with adequate provider data, which had been essentially flat 

from 1997-2012, but also trended downward from 2013-2017. Note that this chart reflects the 

landline sample only. 
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 209

Table G.2: Key Indicators* from Cellular Phone Sample Household and Provider Data 

Collection by Survey Year, National Immunization Survey - Child, 2011-2021†

Survey 

Year§

Resolution 

Rate (%)

Screener 

Completion 

Rate (%)

Interview 

Completion 

Rate (%)

CASRO 

Response Rate 

(%) 

Children with 

Adequate 

Provider Data 

(%) 

2011 47.0 76.2 70.4 25.2 66.7

2012 52.4 77.5 75.5 30.6 63.9

2013 53.8 79.3 71.6 30.5 59.8

2014 58.7 78.5 72.6 33.5 58.9

2015 56.3 79.3 72.2 32.2 55.5

2016 54.0 83.9 70.9 32.1 54.0

2017 43.0 83.7 69.5 25.0 53.6

2018 41.2 84.9 70.3 24.6 54.0

2019 35.2 84.4 71.1 21.1 49.4

2020 36.8 85.7 71.8 22.5 54.2

2021 39.4 84.5 68.8 22.9 51.5

*For the definition of the key indicators see Table 1 of NIS-Child Data User’s Guide for the survey year of interest.

† Excludes U.S. territories. 

§ Cellular phone sample was added to the NIS-Child in 2011.
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 210

Figure G.2: Trends in Cellular Phone Sample Key Indicators from Household and Provider 

Data Collection by Survey Year, National Immunization Survey - Child, 2011-2021*

* Excludes U.S. territories. 

Figure G.2 provides a graphical representation of the data contained in Table G.2. It shows how 

selected cellular phone sample key indicators from the household and provider data collection 

performed from 2011 to present. We observe that the rates since the inception of the cellular phone

sample were fairly flat from 2011 to 2016, with the exception of the percent of children with adequate 

provider data, which fell throughout this period. There was a decline in the resolution rate beginning 

in 2017, leading to a decline in the CASRO response rate. 

The response rate is the number of households with a completed household interview divided by the 

estimated number of eligible households in the sample. Within each sample type (landline or cellular

phone), the number of eligible households was estimated using the CASRO assumptions; these 

0

10

20

30

40

50

60

70

80

90

100

2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021

Percent

Year

Resolution Rate (%)

Screener Completion Rate (%)

Interview Completion Rate (%)

CASRO Response Rate (%)

Children with Adequate Provider Data (%)
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 211

assumptions are that the rate of households among the unresolved telephone numbers is the same as 

the observed rate of households among the resolved telephone numbers, and the rate of eligible 

households among unscreened households is the same as the observed rate of eligible households 

among screened households. Under these assumptions, within each sample type the CASRO response 

rate is equal to the product of the resolution rate, the screener completion rate, and the interview 

completion rate. For the combined samples, we have defined the CASRO response rate as the total 

number of households with a completed interview divided by the estimated total number of eligible 

households across both sample types, where the estimated total number of eligible households is 

equal to the sum of the estimated number of eligible households in the landline sample (using 

CASRO assumptions) and the estimated number of eligible households in the cellular phone sample 

(using CASRO assumptions). Table G.3 presents the CASRO response rate calculated in this way for 

the combined landline and cellular phone samples, by survey year, and Figure G.3 presents a 

graphical representation. Because the CASRO response rate is lower for the cellular phone sample 

than for the landline sample, the CASRO response rate for the combined landline and cellular phone

samples was lower in years with a larger cellular phone sample and higher in years with a smaller 

cellular phone sample.
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 212

Table G.3: CASRO Response Rate for the Combined Landline and Cellular Phone Samples by 

Survey Year, National Immunization Survey - Child, 2011-2017*

Survey Year† CASRO Response Rate (%)

2011 52.2

2012 41.2

2013 34.4

2014 42.5

2015 34.9

2016 33.9

2017 26.1

* Excludes U.S. territories. 

† Cellular phone sample was added to the NIS-Child in 2011. The NIS-Child transitioned from a dual-frame landline and 

cellular phone RDD sample design to a single-frame cellular phone RDD sample design beginning in 2018.

Figure G.3: Trend in CASRO Response Rate for the Combined Landline and Cellular Phone

Samples by Survey Year, National Immunization Survey - Child, 2011-2017*

* Excludes U.S. territories.
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 213

Table G.4: Vaccine-Specific Coverage Levels Among Children Age 19-35 Months in the 

United States by Survey Year, National Immunization Survey - Child, 1995-2021*

Survey 

Year†

4+ 

DTaP

3+ 

Polio

1+ 

MMR

3+ 

Hib§

3+ 

Hep B

1+ 

Varicella¶

4+ 

PCV 4:3:1** 4:3:1:3††

1995 78.4 87.8 89.8 91.2 67.9 N.A. N.A. 76.0 73.7

1996 81.1 91.0 90.6 91.4 81.8 12.0 N.A. 78.4 76.4

1997 81.5 90.7 90.4 92.5 83.6 25.8 N.A. 77.9 76.2

1998 83.9 90.8 92.0 93.4 87.0 43.2 N.A. 80.6 79.2

1999 83.3 89.6 91.5 93.5 88.1 57.5 N.A. 79.9 78.4

2000 81.7 89.5 90.5 93.4 90.3 67.8 N.A. 77.6 76.2

2001 82.1 89.4 91.4 93.0 88.9 76.3 N.A. 78.6 77.2

2002 81.6 90.2 91.6 93.1 89.9 80.6 N.A. 78.5 77.5

2003 84.8 91.6 93.0 93.9 92.4 84.8 N.A. 82.2 81.3

2004 85.5 91.6 93.0 93.5 92.4 87.5 N.A. 83.5 82.5

2005 85.7 91.7 91.5 93.9 92.9 87.9 53.7 83.1 82.4

2006 85.2 92.8 92.3 93.4 93.3 89.2 68.4 83.1 82.2

2007 84.5 92.6 93.2 92.6 92.7 90.0 75.3 82.8 80.1

2008 84.6 93.6 92.1 90.9 93.5 90.7 80.1 82.5 79.6

2009 83.9 92.8 90.0 83.6 92.4 89.6 80.4 81.5 73.4

2010 84.4 93.3 91.5 90.4 91.8 90.4 83.3 82.0 78.8

2011 84.6 93.9 91.6 94.0 91.1 90.8 84.4 82.6 81.9

 2012§§ 82.5 92.8 90.8 93.0 89.7 90.2 81.9 80.5 80.0

2013 83.1 92.7 91.9 92.8 90.8 91.2 82.0 81.5 81.1 

2014 84.2 93.3 91.5 92.6 91.6 91.0 82.9 82.6 82.0

2015 84.6 93.7 91.9 93.2 92.6 91.8 84.1 83.2 82.6

2016 83.4 91.9 91.1 91.6 90.5 90.6 81.8 81.9 81.2

2017 83.2 92.7 91.5 91.8 91.4 91.0 82.4 81.7 80.9

2018 83.8 93.6 92.1 91.6 92.1 92.0 83.3 82.5 81.7

2019 83.3 92.3 91.3 90.9 91.3 90.9 82.5 82.3 81.7

2020 84.2 93.9 92.9 92.4 92.8 92.7 83.2 83.3 82.8

2021 84.4 93.8 92.1 92.6 93.2 91.6 84.6 83.3 82.8

* Excludes U.S. territories. 

† Prior to 2011, estimates are single-frame, landline-sample estimates. From 2011-2017, estimates are dual-frame (landline 

plus cellular phone) estimates. From 2018 onward, estimates are single-frame, cellular phone estimates.

§ Beginning in 2009, the number of doses required to be up-to-date on Hib depends on the manufacturer of the vaccine. 

However, the figures shown here refer to 3 or more doses of Hib vaccine regardless of manufacturer.

¶ Varicella was added to the NIS-Child in 1996.

** Four or more doses of DTaP, three or more doses of poliovirus vaccine, and one or more doses of MCV.

†† Four or more doses of DTaP, three or more does of poliovirus vaccine, one or more doses of MCV, and three or more 

doses of Hib.

§§ Revised definition of adequate provider data (APD) implemented. 
Data User’s Guide for the 2021 NIS-Child Public-Use Data File APPENDIX G 

 214

Figure G.4: Trends in Vaccine-Specific Coverage Levels among Children 19-35 Months of Age 

in the United States by Survey Year, National Immunization Survey - Child, 1995-

2021*†¶

* Excludes U.S. territories. 

† Prior to 2011, estimates are single-frame, landline-sample estimates. From 2011-2017, estimates are dual-frame (landline 

plus cellular phone) estimates. From 2018 onward, estimates are single-frame, cellular phone estimates.

¶ Revised definition of adequate provider data (APD) implemented in 2012. 

Figure G.4 provides a graphical representation of the data contained in Table G.4. It displays the trend 

in vaccine-specific coverage levels among children aged 19 through 35 months from 1995 to present. 

We observe that the trend in the vaccination coverage levels is stable or slightly upward for the 

longer-established vaccines, while the early trends for new vaccines are strongly upward. Note that 

this chart reflects the landline sample prior to 2011, the dual-frame sample in 2011-2017, and the 

single-frame cellular phone sample thereafter. For more information on interpreting trends in 

vaccination coverage, see online reports at https://www.cdc.gov/vaccines/imzmanagers/coverage/childvaxview/pubs-presentations/NIS-vax-trends-2012-2016.html.

0

10

20

30

40

50

60

70

80

90

100

199519961997199819992000200120022003200420052006200720082009201020112012201320142015201620172018201920202021

Percent

Year

4+ DTaP 3+ Polio 1+ MMR 3+ Hib 3+ Hep B

1+ Varicella 4+ PCV 4:3:1** 4:3:1:3
Data User’s Guide for the 2021 NIS-Child Public-Use Data File APPENDIX H 

215

Appendix H: Vaccine Type Codes 

Table H.1: 2021 NIS-Child Vaccine Type Codes

Vaccine Code Description

03 DTaP/DTP/DT-containing, unknown type

04 DTaP/DTP/DT-only

07 DTaP-Hib

08 DTaP-HepB-IPV

20 OPV

21 IPV

22 Polio-containing, unknown type

30 Measles-mumps-rubella

31 Measles-only

32 Measles-mumps

33 Measles-rubella

43 HepB-Hib

44 Hib-only, unknown type

60 HepB-only

70 Pneumococcal conjugate, unknown type

71 Pneumococcal polysaccharide

72 Pneumococcal-containing, unknown type

73 Pneumococcal conjugate-7

74 Pneumococcal conjugate-13

D3 DTaP-IPV-Hib

D4 DTaP-IPV-Hib-HepB

FL Seasonal influenza, unknown type

FM Seasonal influenza spray

FN Injected seasonal influenza

HB HepB-containing, unknown type

HG Hib-only (GSK)

HI Hib-containing, unknown type

HM Hib-only (Merck)

HS Hib-only (Sanofi)

HY Hib-MenCY

MM Measles-containing, unknown type

RG Rotarix (GSK)

RM Rotateq (Merck)

RO Rotavirus-containing, unknown type

VA Varicella-containing, unknown type

VM MMR-varicella

VO Varicella-only
Data User’s Guide for the 2021 NIS-Child Public-Use Data File APPENDIX I 

216

Appendix I: Key NIS-Child Response Rates by Area

Table I.1: Key Indicators* for the Cellular Phone Sample by Estimation Area, National 

Immunization Survey - Child, 2021 

Area Resolution 

Rate (%)

Screener 

Completion 

Rate (%)

Interview 

Completion 

Rate (%)

CASRO 

Response 

Rate (%)

Children with 

Adequate Provider 

Data (%)

U.S. National† 39.4 84.5 68.8 22.9 51.5

Alabama 42.8 85.3 59.7 21.8 49.8

Alaska 59.1 84.0 77.0 38.2 55.3

Arizona 35.0 86.1 62.9 19.0 52.5

Arkansas 47.2 84.6 71.3 28.5 52.9

California 36.3 86.6 63.8 20.1 46.5

Colorado 35.7 88.4 70.2 22.1 54.3

Connecticut 29.2 86.2 70.0 17.6 54.2

Delaware 36.0 79.6 64.5 18.5 46.6

District of Columbia 34.8 80.2 70.5 19.7 46.9

Florida 33.2 86.2 64.2 18.4 49.3

Georgia 37.5 85.7 60.4 19.4 47.7

Hawaii 33.0 83.8 62.8 17.3 51.8

Idaho 34.4 84.7 76.4 22.3 57.8

Illinois 42.5 86.2 66.7 24.5 53.2

 IL-City of Chicago 42.0 84.2 67.7 23.9 53.0

 IL-Rest of State 42.7 86.9 66.4 24.6 53.3

Indiana 39.7 87.0 67.9 23.4 52.2

Iowa 42.5 88.0 72.6 27.1 51.8

Kansas 34.3 86.3 73.6 21.8 55.5

Kentucky 42.9 86.0 68.1 25.1 46.0

Louisiana 40.2 84.2 65.5 22.2 50.1

Maine 42.7 85.8 66.8 24.4 54.1

Maryland 32.2 79.2 70.8 18.0 52.4

Massachusetts 39.3 87.8 68.8 23.7 56.8

Michigan 40.6 85.9 73.4 25.6 50.2

Minnesota 36.7 89.2 69.8 22.8 48.5

Mississippi 45.4 81.5 64.9 24.0 41.1

Missouri 41.9 85.8 75.3 27.1 54.5

Montana 42.4 86.4 68.7 25.2 49.1

Nebraska 31.3 86.8 76.2 20.7 58.6

Nevada 33.7 84.1 68.7 19.5 51.9

New Hampshire 37.7 85.2 68.9 22.1 49.7
Data User’s Guide for the 2021 NIS-Child Public-Use Data File APPENDIX I 

217

Area Resolution 

Rate (%)

Screener 

Completion 

Rate (%)

Interview 

Completion 

Rate (%)

CASRO 

Response 

Rate (%)

Children with 

Adequate Provider 

Data (%)

New Jersey 37.8 85.7 63.7 20.6 46.0

New Mexico 39.9 85.7 70.8 24.2 59.6

New York 35.2 84.8 66.2 19.8 48.1

 NY-City of New York 33.2 83.2 65.4 18.1 48.1

 NY-Rest of State 37.4 87.0 68.2 22.2 48.0

North Carolina 34.4 86.4 66.6 19.8 49.5

North Dakota 51.3 85.3 77.0 33.7 47.0

Ohio 36.5 83.3 75.6 23.0 51.0

Oklahoma 47.6 85.1 65.8 26.6 45.0

Oregon 36.2 88.7 67.5 21.7 57.0

Pennsylvania 35.4 84.6 65.1 19.5 49.5

 PA-Philadelphia County 35.7 84.1 65.5 19.7 45.7

 PA-Rest of State 34.0 87.8 63.0 18.8 51.9

Rhode Island 34.3 83.3 68.9 19.7 52.2

South Carolina 37.4 85.5 60.6 19.4 45.2

South Dakota 45.8 83.5 73.7 28.2 56.3

Tennessee 37.2 83.1 72.0 22.2 52.1

Texas 37.8 84.4 62.8 20.0 50.4

 TX-Bexar County 40.2 83.8 65.7 22.1 47.9

 TX-City of Houston 35.5 84.7 61.4 18.5 48.4

 TX-Rest of State 39.7 85.3 54.2 18.4 52.2

Utah 38.9 85.5 81.0 26.9 63.1

Vermont 40.5 79.4 76.0 24.4 58.0

Virginia 34.5 88.5 68.2 20.8 53.3

Washington 33.7 82.7 77.5 21.6 59.5

West Virginia 43.0 83.3 67.3 24.1 50.1

Wisconsin 41.3 88.2 72.6 26.4 50.3

Wyoming 65.3 80.7 76.4 40.3 52.8

Puerto Rico 40.3 89.2 58.1 20.9 31.1

U.S. Virgin Islands 40.9 86.1 58.0 20.4 42.6

Guam 41.7 73.0 46.7 14.2 45.7

* For the definition of the key indicators see Table 1 of NIS-Child Data User’s Guide. 

† Excludes U.S. territories.