Characteristics of OfficeBased Physicians and Their

Practices: United States,

2005–2006

Series 13, Number 166 April 2008
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Hing E, Burt CW. Characteristics of office-based physicians and their medical

practices: United States, 2005–2006. National Center for Health Statistics. Vital

Health Stat 13(166). 2008.

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Series 13, Number 166

Characteristics of OfficeBased Physicians and Their

Practices: United States,

2005–2006

Data From the National Health Care

Survey

Hyattsville, Maryland

April 2008

DHHS Publication No. (PHS) 2008–1737

U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES

Centers for Disease Control and Prevention

National Center for Health Statistics
National Center for Health Statistics

Edward J. Sondik, Ph.D., Director

Jennifer H. Madans, Ph.D., Acting Co-Deputy Director

Michael H. Sadagursky, Acting Co-Deputy Director

Jennifer H. Madans, Ph.D., Associate Director for Science

Jennifer H. Madans, Ph.D., Acting Associate Director for

Planning, Budget, and Legislation

Michael H. Sadagursky, Associate Director for

Management and Operations

Lawrence H. Cox, Ph.D., Associate Director for Research

and Methodology

Linda B. Torian, Acting Director for Information Technology

Linda B. Torian, Acting Director for Information Services

Linda T. Bilheimer, Ph.D., Associate Director for Analysis

and Epidemiology

Charles J. Rothwell, M.S., Director for Vital Statistics

Jane E. Sisk, Ph.D., Director for Health Care Statistics

Jane F. Gentleman, Ph.D., Director for Health Interview

Statistics

Clifford L. Johnson, M.S.P.H., Director for Health and

Nutrition Examination Surveys

Division of Health Care Statistics

Jane E. Sisk, Ph.D., Director

Robin E. Remsburg, Ph.D., A.P.R.N., B.C., Deputy Director

Catharine W. Burt, Ed.D., Chief, Ambulatory Care Statistics

Branch

Charles Adams, Chief, Technical Services Branch
Contents
 

Abstract ................................................................................................ 1 
 

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

Methods ................................................................................................ 2 
 

Results .................................................................................................. 2 
 

Physician Characteristics................................................................................. 2 
 

Medical Practice Estimates ............................................................................... 3 
 

Revenues and Access ................................................................................... 4 
 

Patient Encounters...................................................................................... 5 
 

Discussion ............................................................................................... 6 
 

References .............................................................................................. 7 
 

Appendix I.............................................................................................. 16 
 

Technical Notes ......................................................................................... 16 
 

Appendix II ............................................................................................. 24 
 

Excerpts from the 2005 Physician Induction Interview Form..................................................... 24 
 

Excerpts from the 2006 Physician Induction Interview Form..................................................... 28 
 

Text Figures

1.	 Percent distribution of office-based physicians, by specialty type, according to survey year: United States, 2001–2006 . . 3
 

2.	 Percentage of office-based medical practices with mid-level providers, by size of practice and breadth of
 

specialization: United States, 2006 ...................................................................... 4 
 

3.	 Percentage of office-based medical practices, by selected diagnostic and therapeutic services available onsite:
 

United States, 2006................................................................................... 4 
 

4.	 Percentage of office-based physicians not accepting new patients, by source of payment and survey year: United States,
 

2001–2006.......................................................................................... 5 
 

5.	 Percentage of office-based physicians who saw patients during the evening or on weekends, by specialty type:
 

United States, 2006................................................................................... 5 
 

6.	 Average number of weekly consultations during last full week of practice, by type of encounter and physician age
 

and sex: United States, 2005–2006 ..................................................................... 6 
 

Detailed Tables

1.	 Number and percent distribution of office-based physicians, with corresponding standard errors, by selected physician
 

characteristics: United States, 2005–2006 ................................................................. 9 
 

2.	 Number and percent distribution of office-based physicians by practice characteristics, and mean percentage of
 

selected practice characteristics, with corresponding standard errors, according to specialty type: United States,
 

2005–2006......................................................................................... 10 
 

3.	 Number and percent distribution of office-based medical practices, with corresponding standard errors, by selected
 

practice characteristics: United States, 2005–2006 ......................................................... 11 
 

4.	 Percent distribution of office-based medical practices and percent distribution of physicians within practices, with
 

corresponding standard errors, by use of electronic medical records and practice ownership: United States,
 

2005–2006......................................................................................... 12 
 

iii
5.	 Percentage of office-based medical practices and physicians within practices reporting selected features of their
 

electronic medical record system, with corresponding standard errors: United States, 2005–2006 ................... 12 
 

6.	 Percentage of office-based physicians by specialty type and physician accessibility, with corresponding standard errors:
 

United States, 2005–2006............................................................................. 13 
 

7.	 Average number of weekly consultations reported during the last full week of practice, and percentage of physicians
 

with selected types of encounters by specialty type, with corresponding standard errors: United States, 2005–2006 .... 13 
 

8.	 Average number of weekly consultations per physician during the last full week of practice, with corresponding
 

standard errors, by type of encounter and practice characteristics: United States, 2005–2006...................... 14 
 

9.	 Average number of weekly consultations per physician during the last full week of practice, by type of encounter and
 

physician specialty, with corresponding standard errors: United States, 2005–2006 .............................. 15 
 

Appendix Tables

I.	 Average number of physicians in the universe, total sample, and sample response categories for the Physician
 

Induction Interview, and unweighted response rate, by physician stratum: National Ambulatory Medical Care Survey,
 

2005–2006......................................................................................... 16 
 

II.	 Characteristics of the 2005–2006 National Ambulatory Medical Care Survey physician respondents and
 

nonrespondents to the Physician Induction Interview ...................................................... 18 
 

III.	 Weighted item nonresponse rates for 2005–2006 report variables............................................. 19 
 

IV.	 Reclassification of physician specialty based on American Medical Association subspecialty designations for use with
 

National Ambulatory Medical Care Survey data........................................................... 20 
 

V.	 Reclassification of physician specialty into specialty type for use with National Ambulatory Medical Care Survey
 

data .............................................................................................. 22 
 

iv
Objectives

This report describes average annual

estimates of nonfederal, office-based

physicians who saw patients in the United

States during 2005–2006. The report also

uses a multiplicity estimator from the

physician sample to estimate the number

and characteristics of medical practices

with which physicians are associated.

Selected physician estimates of

characteristics obtained only in 2006 are

also presented, as well as selected trends

in physician practice characteristics

between 2001–2002 and 2005–2006.

Methods

Data presented in this report were

collected during the induction interview

of physicians during the 2005 and 2006

National Ambulatory Medical Care

Surveys (NAMCS). NAMCS is a

national probability sample survey of

nonfederal physicians who see patients

in an office setting in the United States.

Radiologists, anesthesiologists, and

pathologists—as well as physicians who

treat patients solely in hospital,

institutional, and occupational

settings—are excluded. Sample weights

for physician data use information on

the number of physicians in the

sampled physician’s practice to produce

national estimates of medical practices.

Results

During 2005–2006, an average of

308,900 office-based physicians practiced

in an estimated 163,800 medical practices

in the United States. In 2005–2006, nearly

1 in 10 medical practices were multispecialty groups (8.9 percent) and

accounted for 20.3 percent of all

physicians. In 2006, 11.5 percent of

medical practices employed at least one

mid-level provider and about one-third of

medical practices performed

electrocardiogram (EKG/ECG) tests

(33.5 percent) and lab tests (30.2 percent)

onsite. Between 2001–2002 and

2005–2006, the percentage of physicians

not accepting new Medicaid patients

increased by 16 percent and the

percentage not accepting new charity

cases increased by 23 percent.

Keywords: ambulatory care c

physician c office care c medical

practice

Characteristics of Office-Based

Physicians and Their Medical

Practices: United States,

2005–2006

by Esther Hing, M.P.H., and Catharine W. Burt, Ed.D., Division of

Health Care Statistics

Introduction

Physician offices are the settings

most frequently used for health care,

including the delivery of primary and

specialty care (1). Describing the

characteristics of physicians providing

this care and factors influencing the care

provided is integral for monitoring the

health of the U.S. population and

planning for future health care delivery

needs. NAMCS, which began in 1973,

collects data on the utilization of

ambulatory medical care services

provided by nonfederal office-based

physicians. The survey was conducted

annually until 1981, conducted again in

1985, and resumed an annual schedule

in 1989.

This report presents average annual

estimates of office-based physicians who

see patients and of the medical practices

with which these physicians are

associated. Estimates are based on data

collected during the Physician Induction

Interviews (PII) in the 2005 and 2006

NAMCS. Characteristics presented

include practice characteristics (such as

the physician’s employment status,

ownership of the practice, revenue

sources, use of information technology,

weekly workload, and willingness to

accept new patients) and physician

information from the sample frame (age,

sex, race and ethnicity, whether the

physician graduated from a foreign

medical school, and specialty). The

information complements data on the

utilization of ambulatory medical care

services provided by office-based

physicians (2) by describing

characteristics of the practices and the

physicians within practices providing

care.

Although the 2006 NAMCS sample

included a dual-frame sample of

physicians from office-based practices

and community health centers (CHCs),

only the traditional sample of physicians

that is consistent with the 2005 sample

was included in this report. A separate

report on CHCs will present estimates

of patient visits to CHCs and their

providers.

This report updates previously

published estimates of office-based

physicians (3–5) and estimates of

medical practices, first published using

2003–2004 data (6), with 2005–2006

estimates. The current report differs

from the previous reports by including

in-scope physicians who participated by

completing the PII but were unavailable

during their sample week, and therefore

they did not provide data on sampled

visits. This subset of physicians could

not be included in the 2003–2004

estimates because they did not provide

sufficient useable data during the

induction interview. Inclusion of these

physicians in 2005–2006 estimates

provides a more complete description of

office-based physicians providing patient

care. For the most part, comparisons

with earlier estimates in 2001–2004

were not affected by inclusion of this

subset of physicians who were

unavailable during their sample week in

the 2005–2006 estimates. This is

because their characteristics were

statistically similar to those who

Page 1
Page 2 [ Series 13, No. 166

were available and did provide data on

sampled visits. There were only two

exceptions to this trend: compared with

physicians unavailable during their

sample week, physicians who reported

visit data were more likely to be in

primary specialties and less likely to be

in medical specialties and were more

likely to have been trained in a U.S.

medical school.

Methods

NAMCS is an annual national

probability sample survey of visits to

the offices of physicians classified by

the American Medical Association

(AMA) and American Osteopathic

Association (AOA) as ‘‘office-based,

patient care.’’ Federally employed

physicians; specialists in anesthesiology,

radiology, or pathology; and physicians

who do not see patients in an office—

such as the majority of emergency

medicine physicians—are excluded.

NAMCS utilizes a multistage

probability sample design involving

samples of 112 geographic primary

sampling units (PSUs), physicians

stratified by specialty within PSUs, and

patient visits within physician practices.

PSUs are counties, groups of counties,

county equivalents (such as parishes or

independent cities), or towns and

townships (for some PSUs in New

England). In 2005–2006, 4,054

(63.8 percent) of 6,350 sampled

physicians were found to be eligible for

the survey; of these, 2,592 physicians

participated in the PII for an unweighted

response rate of 63.9 percent.

The induction interview, conducted

at the start of data collection, included

questions to determine physician

eligibility for the survey and to gather

information about the practice, such as

size, ownership, and revenue sources

(see Appendix II for excerpts of the PII

questionnaires). Some characteristics of

physicians are taken from the master

files of the AMA and AOA, including

age, sex, race and ethnicity, foreign

medical school graduate, specialty,

geographic region, and metropolitan

statistical area status. Many of the tables

present estimates by physician specialty,

and two methods of categorizing

physician specialty are used in this

report. The first method reflects the

NAMCS sample strata of 13 major

specialty groupings, and the second uses

three broad types of specialty (primary

care, surgical, and medical specialties).

See Appendix I for definitions. Both

methods are based on the specific

self-designated subspecialty codes

provided by the AMA and AOA on the

sampling frame and updated by the

physician during the NAMCS induction

interview.

Sampling weights reflecting the

multistage sample of physicians and

nonresponse adjustments were used to

make annual national estimates of

physicians. Because estimates presented

in this report are based on sample

surveys rather than the universe of

office-based physicians, they are subject

to sampling variability. Appendix I

includes an explanation of the sampling

errors with guidelines for judging the

precision of the estimates and

information on physician and item

nonresponse. Standard errors are

calculated using Taylor series

approximations in SUDAAN, which

take into account the complex sample

design of the NAMCS (7). In this

report, estimates are not presented if

they are based on fewer than 20 cases in

the sample data; only an asterisk (*)

appears in the tables. The relative

standard error (RSE) of an estimate is

obtained by dividing the standard error

by the estimate itself. The result is then

expressed as a percentage of the

estimate. Estimates based on 20–29

cases are also presented with asterisks

(*) regardless of the RSE level.

Estimates based on 30 or more cases

include an asterisk (*) if the RSE of the

estimate exceeds 30 percent.

In this report, percentages based on

categorical responses were computed

with missing data (‘‘unknown’’ or blank)

in the denominator so that responses

represent all physicians. This method

may understate percentages if the

distribution among unknowns is similar

to the distribution among responses.

(See Appendix I for information on

missing data for characteristics

presented in the report.)

Chi-square tests using SUDAAN

were performed to detect significant

associations between provider

characteristics. All other tests of

statistical significance between two

estimates are based on the two-tailed

t-test at the 0.05 level of significance,

unless otherwise noted. Terms relating

to differences, such as ‘‘greater than’’ or

‘‘less than,’’ indicate that the difference

is statistically significant. A lack of

comment regarding the difference

between any two estimates does not

mean that the difference was tested and

found to be not significant.

The data collection agent for

NAMCS is the U.S. Census Bureau, and

the data are centrally processed by

Constella Group, Inc. There is

100 percent independent keying of the

induction forms with a quality control

error rate of 0.1 percent. More

information about the data collection

procedures and survey background may

be found elsewhere (8,9).

Results

Physician Characteristics

Table 1 provides national estimates

of office-based physicians by

characteristics available from the

sampling frame. During 2005–2006,

308,900 office-based physicians on

average were in practice on any given

week in the United States. The overall

rate of 105.5 physicians per 100,000

persons in 2005–2006 has remained

stable since 2001–2002 (105.4

physicians per 100,000 persons) and

2003–2004 (108.4 physicians per

100,000 persons) (5). One-third of

physicians (34.3 percent) were aged

45–54 years at the time of the survey.

Since 2001–2002, mean physician age

has increased from 49.7 years to 50.4

years (data not shown).

About one in four office-based

physicians (24.1 percent) were female

(Table 1). Since 2001–2002, the

percentage of office-based physicians

who were female increased by

24 percent, from 19.4 percent to

24.1 percent in 2005–2006 (3,4). The

distribution of physicians by race and
ethnicity is presented in Table 1. These

data should be viewed with caution,

however, because item nonresponse

from the sample frame for physician

race or ethnicity was 25 percent (see

Appendix I). During 2005–2006,

23.0 percent of office-based physicians

were graduates of medical schools

outside of the United States (Table 1).

The percentage of office-based

physicians who graduated from foreign

medical schools has been stable since

2001–2002 (5).

About one-half of all physicians

practiced in primary care specialties

(50.0 percent). About 28.6 percent of

physicians were in medical specialties,

whereas 21.5 percent were in surgical

specialties. Since 2001–2002, the

proportion of physicians in medical

specialties increased by 22 percent,

whereas the proportion in surgical

specialties decreased by 18 percent

(Figure 1). Specialties with the most

physicians included general and family

practice (18.5 percent), internal medicine

(14.3 percent), pediatrics (10.1 percent),

and obstetrics and gynecology

(7.7 percent).

In 2005–2006, more physicians

practiced in the South (35.7 percent), the

region with the largest percentage of the

population, than in other regions

(20.8 percent to 22.8 percent). Nearly 9

out of 10 physicians practiced in urban

metropolitan areas (89.2 percent).

On the basis of the office location

where physicians saw the most patients,

about one-third of the physicians were

in solo practices (36.8 percent), whereas

9.1 percent were in practices with 11 or

more physicians (Table 2). About

four-fifths of physicians (78.8 percent)

were in solo or single-specialty group

practices, whereas 20.3 percent were in

multispecialty group practices. The

majority of physicians were the owners

or part owners of their practices

(70.0 percent). Primary care specialists

were employees more frequently

(29.8 percent) than surgical specialists

(19.0 percent); surgical specialists were

more likely to own their practice

(78.2 percent) than primary care

specialists (65.2 percent) (Table 2).

Medical Practice Estimates

Examining characteristics of

medical practices provides another

perspective on the organization and

delivery of office-based ambulatory

care. Although 36.8 percent of

office-based physicians were in solo

practice, 69.4 percent of medical

practices consisted of solo practitioners

0 

10 

20 

30 

40 

50 

60 

Medical1 

Surgical1 

Primary care 

2001–2002 2003–2004 2005–2006 1

Trend is statistically significant (p < 0.05). 

SOURCE: CDC/NCHS, National Ambulatory Medical Care Survey. Percent of physicians 

Figure 1. Percent distribution of office-based physicians, by specialty type, according to

survey year: United States, 2001–2006

Series 13, No. 166 [ Page 3

(Tables 2 and 3). On the other hand,

practices with three or more physicians,

which account for one-fifth of medical

practices, contained about one-half of all

office-based physicians. In 2005–2006,

nearly 1 in 10 medical practices were

multispecialty groups (8.9 percent), and

these practices accounted for

20.3 percent of all physicians.

Multispecialty group practices were

larger, averaging 8.6 physicians, than

solo and single specialty practices (3.4

physicians, on average). The distribution

of medical practices has not changed

between 2003–2004 and 2005–2006 for

these characteristics.

Decisions affecting patient care

services, such as staffing, availability of

onsite tests, provision of after-hours

care, and adoption of clinical

information technology, may be made at

the organization level of the medical

practice rather than by individual

physicians. In 2006, new information

was collected on availability of

mid-level providers (physician assistants,

nurse practitioners, and certified nurse

midwives) and presence of onsite

imaging, treatments, and tests. In 2006,

11.5 percent of medical practices

employed at least one mid-level

provider. Availability of mid-level

providers was greater among multispecialty groups than among solo

practitioners or single-specialty groups

and increased with size of practice

through practices with 3–5 physicians

(Figure 2). Among medical practices,

EKG/ECG tests (33.5 percent) and lab

testing (30.2 percent) were the

diagnostic and therapeutic services most

often available at practice locations

(Figure 3). Imaging studies were less

frequently available onsite (Figure 3),

ranging from MRI (i.e., magnetic

resonance imaging) (2.1 percent) to

ultrasound (13.8 percent) and x-ray

images (16.1 percent). With the

exception of PET (i.e., positron emission

tomography) scans, all of the onsite

diagnostic and therapeutic services were

available more frequently among

multispecialty groups than among solo

practitioners or single-specialty groups

(data not shown).

Between 2003–2004 and

2005–2006, use of fully or partially
Page 4 [ Series 13, No. 166

1

Practice size is number of physicians at practice location where most patients were seen. Availability of 

mid-level providers increased with practice size through practices with three to five physicians (p < 0.05). 

SOURCE: CDC/NCHS, National Ambulatory Medical Care Survey. 

Percent of medical practices 

Practice size1 

Breadth of 

specialization 

0 5 10 15 20 25 30 

Multi-specialty

 group 

Solo and singlespecialty group 

11 or more 

6–10 

3–5 

Partner 

Solo 

All practices 11.5 

6.1 

16.0 

18.5 

18.3 

10.3 

23.3 

28.7 

Figure 2. Percentage of office-based medical practices with mid-level providers, by size of

practice and breadth of specialization: United States, 2006

EKG/ECG
 

Lab test
 

X ray
 

Spirometry
 

Ultrasound
 

Sigmoidoscopy 

Chemotherapy 

Mammography 

CT scan 

MRI 

PET scan 

0 5 10 15 20 25 30 35 40 

33.5 

30.2 

16.1 

15.3 

13.8 

3.0 

2.9 

2.8 

2.1 

*1.5 

5.0 

Percent of medical practices *

Figure does not meet standards of reliability or precision.
 

NOTES: EKG/ECG is electrocardiogram. CT is computed tomography. MRI is magnetic resonance imaging. 


PET is positron emission tomography. Although a question on radiation therapy was asked, no physicians reported that 


this therapy was performed onsite.
 

SOURCE: CDC/NCHS, National Ambulatory Medical Care Survey.
 

Figure 3. Percentage of office-based medical practices, by selected diagnostic and

therapeutic services available onsite: United States, 2006

electronic medical records (also known 2005–2006, nearly two-thirds

as EMRs) by medical practices (63.3 percent) of HMO (i.e., health

increased by 46 percent from maintenance organization) medical

15.0 percent in 2003–2004 to practices were using full or partial

21.9 percent in 2005–2006 (6). In electronic medical records (Table 4).

Use of computerized prescription order

entry among all medical practices nearly

doubled between 2003–2004

(6.5 percent) and 2005–2006

(12.5 percent) (Table 5) (6).

Revenues and Access

During 2005–2006, 83.2 percent of

physicians reported having at least one

managed care contract and 11.0 percent

had none, whereas this information was

missing for 5.8 percent (Table 2). About

34.7 percent of physicians reported

having between 3 and 10 managed care

contracts, whereas 39.4 percent reported

10 or more contracts. Of practices

reporting at least one managed care

contract, the mean percentage of

revenue from these contracts was

47.2 percent. The mean percentage of

revenue from managed care contracts

was higher among primary care

specialists (51.2 percent) than among

surgical (42.4 percent) or medical

specialists (43.3 percent).

The NAMCS PII included questions

about the percentage of practice revenue

from various payment sources (Table 2).

Private insurance accounted for about

one-half of office revenue (on average,

45.2 percent) and Medicare accounted

for an average of 29.7 percent of

revenue among physicians reporting this

information. Primary care specialists

reported a higher mean percentage of

revenue from private insurance

(49.2 percent) and Medicaid

(17.4 percent) than surgical or medical

specialists (Table 2). The mean

percentage of Medicare revenues,

however, was higher among surgical

(36.8 percent) and medical

(34.6 percent) specialists than among

primary care specialists (23.8 percent).

When physicians were asked if they

were currently accepting new patients

into their practice, 91.9 percent

responded positively (Table 6), a

3 percent decrease since 2001

(94.8 percent) (3). In 2005–2006,

responses varied by the payment sources

physicians accepted from new patients

(40.5 percent to 85.6 percent). Figure 4

presents trends in the percentage of

physicians who reported payment

sources that they did not accept from
Series 13, No. 166 [ Page 5

36.5 No charge 40.3 or charity1 

44.8 

Worker's 33.9

35.5 compensation1 

40.9 

36.5 

private 

Capitated

36.8
 

insurance
 38.9 

24.3
 

Medicaid1
 25.5 

28.3 

2001–2002 

15.6
 

Medicare
 13.9 2003–2004 16.3 

Noncapitated 12.1 2005–2006 

private 11.0
 

insurance
 12.4 

6.2
 

Self-pay1
 6.0 

8.7 

0 10 20 30 40

Percent of physicians 1

Trend is statistically significant (p < 0.05).
 

SOURCE: CDC/NCHS, National Ambulatory Medical Care Survey.
 

Figure 4. Percentage of office-based physicians not accepting new patients, by source of

payment and survey year: United States, 2001–2006

50 

0 

10 

20 

30 

40 

Medical1 Surgical1 Primary

 care 

All 

physicians 

1

Difference with primary care specialists is statistically significant (p < 0.05). 

SOURCE: CDC/NCHS, National Ambulatory Medical Care Survey. 

26.6 

37.1 

16.6 16.0

Percent of physicians 

Figure 5. Percentage of office-based physicians who saw patients during the evening or on

weekends, by specialty type: United States, 2006

new patients. The percentage of new charity cases (as defined by the

physicians not accepting new Medicaid ‘‘no charge/charity’’ check box), a

patients (28.3 percent) in 2005–2006 23 percent increase since 2001–2002. A

represents a 16 percent increase since similar pattern was observed for primary

2001–2002. In 2005–2006, 44.8 percent care specialists; primary care specialists

of office-based physicians did not accept not accepting new charity patients

increased by 23 percent, from

39.8 percent in 2001–2002 to

49.0 percent in 2005–2006 (data not

shown). For this analysis, when

physicians reported not accepting any

new patients, their responses were edited

to ‘‘no’’ for each of the specific

payment sources. ‘‘No’’ responses may

be understated if the amount of missing

data is large because each percentage

includes unknowns in the denominator.

The percentage with missing data for

these items ranged from 5.7 percent for

self-pay to 14.7 percent for no charge or

charity (see Appendix I for further

information).

Physicians may not accept new

patients because they are operating at

capacity. In 2006, new information was

collected in NAMCS on whether the

physician saw patients in the office

during the evening or on weekends.

Figure 5 shows that 26.6 percent of

physicians saw patients after office

hours in 2006. Primary care specialists

were more likely to see patients during

nonoffice hours (37.1 percent) than were

surgical (16.6 percent) or medical

specialists (16.0 percent).

Physicians also reported on any

difficulty they had referring certain

types of patients for specialty care

(Table 6). Physicians had the least

difficulty referring Medicare and

privately insured patients. About

one-third had difficulty referring

Medicaid and uninsured patients.

Patient Encounters

Another practice characteristic

collected in the PII is the number of

encounters the physician had during his

or her last full week of practice prior to

the interview (Table 7). During

2005–2006, the average number of

office visits reported for physicians

having any visits that week was 73.4

visits per week, representing an

8 percent decline since 2001 (3).

Other types of physician-patient

encounters reported during the last full

week of practice included hospital visits,

telephone consultations, home visits, and

Internet or e-mail consultations. During

2005–2006, 56.8 percent of physicians

reported making at least one hospital

visit, 50.7 percent had at least one
Page 6 [ Series 13, No. 166

telephone consultation, 8.8 percent made

one or more house visits (including

visits to nursing homes), and 6.0 percent

reported having an email or Internet

consultation during the week. During

2005–2006, surgical specialists were

more likely to make a hospital visit in

their last full week of work

(66.6 percent) compared with the other

types of specialties. The 2005–2006

estimates indicate the following declines

since 2001: the percentage of physicians

reporting hospital visits declined by

26 percent, telephone consultations

declined by 31 percent, and home visits

declined by 51 percent (3).

Some physicians may have provided

care in the emergency department (ED)

during their hospital visits. The

Emergency Medical Treatment and

Labor Act (EMTALA) of 1986 requires

all hospitals accepting Medicare funding

to screen all patients presenting to the

ED for care and to stabilize emergency

medical conditions before transferring or

discharging patients from the ED (10).

In 2005–2006, such care was provided

by 9.2 percent of physicians during their

last full week of practice; at that time,

they provided, on average, 11.0 hours of

care (Table 7). Surgical specialists were

more likely to have provided EMTALA

care during the week (12.5 percent) than

were primary care specialists

(7.9 percent).

Table 8 shows the average weekly

number of consultations for all

physicians during their last full week of

practice, as well as those that occurred

during office visits, hospital visits, and

telephone consultations across practice

characteristics. To approximate total

volume of patient consultations made by

office-based physicians during their last

full week of practice, all types of

consultations conducted by telephone,

email, or Internet, or consultations

conducted during any patient visit

occurring inside or outside of the office

(house or hospital visit) were summed,

including those for physicians with zero

encounters in Table 8 (in contrast to

Table 7, which excludes physicians

reporting zero encounters). In

2005–2006, office-based physicians had

an average of 92.7 patient encounters

during their last full week of work. This

includes an average of 71.9 office visits,

65 years

 and over 

55–64 years 

45–54 years 

35–44 years 

Under

 35 years 

Female 

Male 

0 

Hospital visits1,2 

Office visits1 

Total consultations1,3 

20 40 60 80 100

Number of consultations 

1

Differences by gender and between physicians under 65 years of age and 65 years of age and over are 


statistically significant (p < 0.05). 
 2

Differences between physicians aged 35-64 years and 65 years and over are statistically significant (p < 0.05). 
 3

Total consultations include patient encounters in the office, at the hospital, at home, over the 


telephone, and over the Internet. Average is calculated across all physicians, including those who reported 


zero values for any of these items.


 SOURCE: CDC/NCHS, National Ambulatory Medical Care Survey.
 

Figure 6. Average number of consultations during last full week of practice, by type of

encounter and physician age and sex: United States, 2005–2006

10.0 hospital visits, 8.8 telephone

consults, 1.3 home visits, and 0.6 email

consultations (last two estimates not

shown). Although the total volume of

consultations was greater for primary

care specialists (105.6 encounters

compared with 78.4 encounters for

medical specialties and 81.6 encounters

for surgical specialties), hospital visits

were more frequent among medical

specialties (13.4 visits compared with

7.7 visits for primary care specialists

and 11.0 visits for surgical specialties).

Office volume and total volume

increased with the number of managed

care contracts that physicians reported

(Table 8), driven by the positive

associations between office visit volume

and the number of contracts among

primary care and medical specialists

(data not shown).

Table 9 presents the average weekly

volume of consultations by physician

specialty. Although dermatologists had

the highest average volume of office

visits, they were among specialties with

the lowest average volume of hospital

visits. The average weekly volume of

consultations also varied by physician

age and sex (Figure 6). Female

physicians had fewer weekly encounters

overall compared with male physicians,

including office visits and hospital

visits. Physicians aged 65 years and

over had fewer weekly encounters

overall, as well as fewer office visits

compared with physicians under 65

years of age. Physicians aged 65 years

and over had fewer hospital visits than

physicians aged 35–64 years.

Discussion

This report presents nationally

representative estimates of office-based

medical practices and physicians within

these practices who saw patients during

2005–2006 and selected physician and

medical practice characteristics available

only for the 2006 survey. The report

updates previously published estimates

of medical practices (first published

with 2003–2004 data) (6) and

office-based physicians (3–5,11–14)

since 2001–2002.

As measured by the ratio of

office-based physicians to the U.S.

civilian, noninstituional population, the

report found no change in the per capita

supply of office-based physicians

between 2001–2002 and 2005–2006.

The stability in the supply of practicing
Series 13, No. 166 [ Page 7

physicians may have been affected by

the availability of mid-level providers in

physician practices as potential

caregivers. In 2006, 11.5 percent of

medical practices reported using

mid-level providers, and 16.5 percent of

all physicians reported mid-level

providers at their practices. A previous

study found that the proportion of

physicians in noninstitutional practice

settings employing mid-level providers

increased from 40 percent to 48 percent

between 1997 and 2001 (15).

Although the supply of practicing

physicians remained stable between

2001–2002 and 2005–2006, the finding

that fewer physicians accepted new

patients in 2005–2006 may indicate

access problems for certain patients. The

study found that the percentage of

physicians not accepting new charity

patients or new Medicaid patients

increased between 2001–2002 and

2005–2006. These findings may indicate

access problems among physicians

providing care for Medicaid patients.

Despite decreasing access for some

new patients, some physicians provided

flexible office hours for patient care. In

2006, 26.6 percent of physicians saw

patients in the office during evenings or

on weekends. Primary care specialists

were more likely to see patients during

the evening or on weekends than were

surgical or medical specialists.

The report found a trend of

physicians’ having fewer patient

encounters during their last complete

week of practice. Between 2001 and

2005–2006, the average number of

office visits declined by 8 percent,

whereas the percentage of physicians

reporting hospital visits declined by

26 percent, the percentage reporting

telephone consultations declined by

31 percent, and the percentage making

home visits declined by 51 percent (3).

These estimates support previous studies

that found physicians have reduced the

number of hours they work (16,17).

Two factors may be related to

physicians’ working fewer hours. First,

the pool of physicians is aging. In

2005–2006, the median age of

office-based physicians was 50 years of

age. With one-half of office-based

physicians being 50 years of age and

over, some physicians may work fewer

hours because they are nearing

retirement age. This study found that

most physicians dramatically reduced

their volume of patient encounters after

they reach 65 years of age. Second, the

proportion of office-based female

physicians is increasing (24.1 percent in

2005–2006, compared with 19.4 percent

in 2001–2002). According to the

Association of American Medical

Colleges, the percentage of female

medical school graduates increased

77 percent between 1980–1981 and

2002–2003, from 26.5 percent to

46.8 percent (18). The setting that saw

the largest increase in female physicians

during this period was the office-based

practice (567 percent increase) (19).

This study found that female physicians

had fewer patient encounters during

their last full week of practice than male

physicians, primarily because of fewer

office and hospital visits. These findings

in part explain the decrease in total

hours worked by physicians. Previous

research also found that female

physicians generally work fewer hours

than male physicians even when

part-time status is taken into account

(16,17).

The practice pattern of working

fewer hours reduces the relative supply

of physicians available to provide

patient care (20). As the baby boom

population ages, demand for physician

services is expected to increase (20).

In addition to updating physician

characteristics, this study describes

characteristics of medical practices in

2005–2006. The study found that

multispecialty group practices not only

averaged more physicians in the practice

than solo practices or single-specialty

groups, but they also had more

mid-level providers and provided chemo

therapy and other tests and imaging

onsite more often than solo practices or

single-specialty group practices. Use of

clinical health information technology

by all medical practices increased by

46 percent since 2003–2004, and use of

computerized prescription order entry

features of these systems increased by

92 percent. Although these trends show

progress, a previous report found that

use of comprehensive electronic medical

record systems (which, at a minimum,

included prescription and test order

entry features, as well as the ability to

see test results and clinical notes

electronically) by medical practices

remained stable between 2003–2004 and

2005–2006 (14).

The previous discussion illustrates

how physician data may be used to

track multiple issues affecting the

supply and practice characteristics of

office-based physicians. Further research

is warranted to examine these issues in

more depth.

Additional information about

office-based physicians is available from

the National Center for Health Statistics

(NCHS) Ambulatory Health Care

website at http://www.cdc.gov/nchs/

about/major/ahcd/ahcd1.htm. Data from

the 2005–2006 NAMCS PII are

available through the NCHS Research

Data Center. Queries regarding NAMCS

data may be sent to NCHS via

nchsquery@cdc.gov.

References

1.	 Burt CW, McCaig LF, Rechtsteiner EA.

Ambulatory medical care utilization

estimates for 2005. Advance data from

vital and health statistics; no 388.

Hyattsville, MD: National Center for

Health Statistics. 2007.

2.	 Cherry DK, Woodwell DA,

Rechtsteiner EA. National Ambulatory

Medical Care Survey: 2005 summary.

Advance data from vital and health

statistics; no 387. Hyattsville, MD:

National Center for Health Statistics.

2007.

3.	 Cherry DK, Burt CW, Woodwell DA.

National Ambulatory Medical Care

Survey: 2001 summary. Advance data

from vital and health statistics; no 337.

Hyattsville, MD: National Center for

Health Statistics. 2003.

4.	 Woodwell DA, Cherry DK. National

Ambulatory Medical Care Survey: 2002

summary. Advance data from vital and

health statistics; no 346. Hyattsville,

MD: National Center for Health

Statistics. 2004.

5.	 Hing E, Burt CW. Characteristics of

office-based physicians and their

practices: United States, 2003–04.

National Center for Health Statistics.

Vital Health Stat 13(164). 2007.

6.	 Hing E, Burt CW. Office-based medical

practices: Methods and estimates from

the National Ambulatory Medical Care
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Survey. Advance data from vital and

health statistics; no 383. Hyattsville,

MD: National Center for Health

Statistics. 2007.

7.	 Research Triangle Institute. SUDAAN

user’s manual, release 8.0. Research

Triangle Park, NC: Research Triangle

Institute. 2002.

8.	 National Center for Health Statistics.

Public-use data file documentation.

2005 National Ambulatory Medical

Care Survey. Hyattsville, MD.

Available from: http://www.cdc.gov/

nchs/about/major/ahcd/ahcd1.htm. 2007.

9.	 National Center for Health Statistics.

Public-use data file documentation.

2006 National Ambulatory Medical

Care Survey. Hyattsville, MD. 2006. In

preparation.

10.	 Burt CW, McCaig LF. Trends in

hospital emergency department

utilization: United States, 1992–99.

National Center for Health Statistics.

Vital Health Stat(13)150. 2001.

11.	 Burt CW, Hing E. Use of computerized

clinical support systems in medical

settings: United States, 2001–03.

Advance data from vital and health

statistics; no. 553. Hyattsville, MD:

National Center for Health Statistics.

2005.

12.	 Burt CW, Sisk JE. Which physicians

and practices are using electronic

medical records? Health Aff

24(5):1334–43. 2005.

13.	 Burt CW, Hing E. Electronic medical

record use by office-based physicians:

United States, 2005 [online]. Available

from: http://www.cdc.gov/nchs/

products/pubs/pubd/hestats/electronic/

electronic.htm [cited 2007 Aug 10].

2006.

14.	 Hing E, Burt CW, Woodwell DA.

Electronic medical record use by

office-based physicians and their

practices: United States, 2006. Advance

data from vital and health statistics; no.

393. Hyattsville, MD: National Center

for Health Statistics. 2007.

15.	 Trude S. So much to do, so little time:

Physician capacity constraints,

1997–2001. Center for Health Systems

Change. Tracking Report No. 8. May

2003.

16.	 Weeks WB, Wallace AE. Time and

money: A retrospective evaluation of

the inputs, outputs, efficiency, and

incomes of physicians. Arch Intern

Med 163(8):944–8. 2003.

17.	 Hadley J, Mitchell JM. Effects of HMO

market penetration on physicians’ work

effort and satisfaction. Health Aff

16(6):99–111. 1997.

18.	 Cooper R. Medical schools and their

applicants: An analysis. Health Aff

22(4):71–96. 2003.

19.	 Smart D. Physician characteristics and

distribution in the US: 2006 edition.

Department of Data Quality and

Measurement, Division of Data and

Operations. Chicago, IL: American

Medical Association. 2006.

20.	 Salsberg E, Grover A. Physician

workforce shortages: Implications and

issues for academic health centers and

policymakers. Acad Med 81(9):782–7.

2006.

21.	 Thran S. American Medical Association

[personal communication]. July 6,

2006.

22.	 Gans D, Kralewski J, Hammons T,

Dowd B. Medical groups’ adoption of

electronic health records and

information systems. Health Aff

24(5):1323–33. 2005.
Series 13, No. 166 [ Page 9

Table 1. Number and percent distribution of office-based physicians, with corresponding standard errors, by selected physician

characteristics: United States, 2005–2006

Selected physician characteristics1

Number of

physicians2

Standard

error

Percent

distribution

Standard

error of

percent

Total .......................................... 308,900 8,100 100.0 . . .

Age

Under 35 years ....................................

35–44 years ......................................

45–54 years ......................................

55–64 years ......................................

65 years and over ..................................

15,800

85,600

106,000

75,300

26,200

1,700

4,100

4,900

3,500

2,000

5.1

27.7

34.3

24.4

8.5

0.5

1.1

1.1

1.1

0.6

Sex

Male. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Female . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

234,500

74,400

6,700

4,000

75.9

24.1

1.1

1.1

Race and ethnicity

Non-Hispanic white..................................

Non-Hispanic black..................................

Asian or Pacific Islander ..............................

Hispanic ........................................

Other or unknown ..................................

173,000

6,900

33,100

8,200

87,700

6,900

1,000

2,800

1,200

4,200

56.0

2.2

10.7

2.6

28.4

1.4

0.3

0.9

0.4

1.2

Graduate of foreign medical school

No . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Yes ...........................................

Unknown ........................................

218,800

71,100

19,000

8,200

3,800

1,700

70.8

23.0

6.2

1.3

1.2

0.6

Specialty type3

Primary care . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Medical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Surgical. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

154,400

88,200

66,300

5,100

3,600

2,900

50.0

28.6

21.5

0.9

0.9

0.8

Physician specialty4

General and family practice ............................

Internal medicine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Pediatrics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Obstetrics and gynecology .............................

Psychiatry .......................................

Orthopedic surgery ..................................

Cardiovascular diseases ..............................

Opthalmology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

General surgery....................................

Dermatology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Urology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Neurology .......................................

Otolaryngology ....................................

All other specialties..................................

57,300

44,000

31,100

23,700

17,800

15,100

13,200

12,800

11,300

7,200

6,600

6,300

5,900

56,500

2,600

2,600

1,500

1,100

900

1,100

800

900

800

600

400

300

400

3,000

18.5

14.3

10.1

7.7

5.8

4.9

4.3

4.1

3.6

2.3

2.1

2.0

1.9

18.3

0.7

0.7

0.4

0.3

0.3

0.3

0.2

0.3

0.3

0.2

0.1

0.1

0.1

0.8

Geographic region

Northeast........................................

Midwest. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

South . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

West. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

64,200

64,000

110,200

70,400

3,800

3,000

5,500

3,600

20.8

20.7

35.7

22.8

1.1

0.9

1.4

1.0

Metropolitan status

MSA5 ..........................................

Non-MSA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

275,600

33,300

8,400

4,700

89.2

10.8

1.5

1.5

. . . Category not applicable.
 

1

Characteristic information is from the master files of the American Medical Association and the American Osteopathic Association.
 

2

Number of nonfederal office-based physicians during 2005–2006, excluding the specialties of radiology, pathology, and anesthesiology. Estimates are rounded to the nearest hundred.
 

3

Specialty type is defined in Appendix I, Table V.
 

4

Physician specialty is defined in Appendix I, Table IV.
 

5

MSA is metropolitan statistical area.
 
Page 10 [ Series 13, No. 166

Table 2. Number and percent distribution of office-based physicians by practice characteristcs, and mean percentage of selected practice

characteristics, with corresponding standard errors, according to specialty type: United States, 2005–2006

Specialty type1 Specialty type1

All Primary All Primary

Practice characteristics specialties care Surgical Medical specialties care Surgical Medical

Annual number of physicians Standard error

All office-based physicians ................. 308,900 154,400 66,300 88,200 8,100 5,100 2,900 3,600

Percent distribution

All physicians ......................... 100.0 100.0 100.0 100.0 . . . . . . . . . . . .

Number of in-scope office locations

One ............................... 86.1 90.3 78.9 84.2 0.8 1.0 1.9 1.5

More than one. . . . . . . . . . . . . . . . . . . . . . . . . 13.2 8.8 20.5 15.5 0.8 0.9 1.9 1.5

Unknown ............................ *0.7 *0.9 *0.6 *0.4 0.2 0.3 0.4 0.2

Practice size2

Solo ............................... 36.8 35.2 34.7 41.0 1.2 1.9 2.3 2.1

Partner ............................. 12.1 13.7 10.7 10.3 0.8 1.3 1.6 1.2

3–5 ............................... 27.8 28.8 30.5 23.9 1.0 1.6 2.1 1.7

6–10 .............................. 14.3 14.2 14.1 14.6 0.8 1.4 1.6 1.4

11 or more .......................... 9.1 8.1 10.0 10.1 0.8 1.1 1.4 1.2

Breadth of specialization

Solo or single-specialty group ............... 78.8 75.0 82.5 82.6 1.1 1.7 1.8 1.7

Multispecialty group ..................... 20.3 23.9 16.2 17.0 1.1 1.7 1.8 1.7

Unknown ............................ 1.0 *1.1 *1.3 *0.4 0.2 0.4 0.5 0.2

Employment status

Owner. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70.0 65.2 78.2 72.3 1.4 1.9 2.2 2.0

Employee ........................... 25.7 29.8 19.0 23.4 1.3 1.8 2.0 1.9

Contractor ........................... 4.3 5.0 2.7 4.3 0.5 0.8 0.7 0.9

Ownership3

Solo or partner practice ................... 44.0 42.8 43.8 46.2 1.3 2.1 2.4 2.1

Group practice ........................ 38.8 36.1 46.4 37.9 1.2 1.9 2.2 2.1

HMO4 .............................. 2.8 2.8 1.8* 3.4 0.5 0.6 0.6 0.8

Other office setting5 ..................... 14.4 18.2 7.9 12.5 1.2 1.7 1.2 1.4

Participates in practice-based research network

Yes ............................... 4.5 2.7 5.0 7.1 0.6 0.5 1.2 1.2

No ................................ 81.8 83.6 82.8 78.0 1.1 1.3 1.8 1.9

Unknown ............................ 13.7 13.7 12.2 14.9 1.0 1.4 1.5 1.7

Number of managed care contracts

None .............................. 11.0 9.0 9.5 15.7 0.8 1.2 1.5 1.4

1–2 ............................... 9.1 8.5 9.8 9.5 0.8 1.1 1.5 1.3

3–10............................... 34.7 36.9 33.2 31.8 1.4 1.9 2.4 2.0

More than 10 ......................... 39.4 39.8 41.7 37.0 1.8 2.1 2.7 2.4

Unknown ............................ 5.8 5.8 5.8 6.0 0.6 0.9 1.0 1.1

Mean percent6

Percentage of revenue from managed care contracts. 47.2 51.2 42.4 43.3 1.4 1.6 1.7 2.0

Mean percent7

Percent of revenue from selected sources8

Private insurance ....................... 45.2 49.2 40.2 41.8 0.7 1.0 1.0 1.2

Medicare ............................ 29.7 23.8 36.8 34.6 0.6 0.7 1.0 1.1

Medicaid . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.0 17.4 10.2 11.0 0.5 0.7 0.6 0.7

Other sources ......................... 12.3 11.0 12.1 14.5 0.6 0.9 1.1 1.2

. . . Category not applicable.

* Figure does not meet standards of reliability or precision.
 

1

Specialty type is defined in Appendix I, Table V.
 

2

Practice size is number of physicians in practice associated with location where most patients were seen. Practice size was randomly assigned for 1.6 percent of physicians missing this information.
 

3

Ownership of practice is based on location where most patients were seen.
 

4

HMO is health maintenance organization.
 

5

Other setting includes ownership by community health center, medical academic health center, other hospital, other health care corporation, other, or unknown.
 

6

Mean percentage among physicians with any managed care revenue. Information on managed care revenue was missing for 26 percent of physicians with any managed care contract.
 

7

Mean percentage of revenue among physicians with any revenue from source.
 

8

Information on percentage of revenue from selected sources was missing for 11 percent to 15 percent of physicians depending on type of payment source.
 
Series 13, No. 166 [ Page 11

Table 3. Number and percent distribution of office-based medical practices, with corresponding standard errors, by selected practice

characteristics: United States, 2005–2006

Selected practice characteristics

Number of

practices1

Standard

error

Percent

distribution

Standard

error

Total ............................................... 163,800 5,500 100.0 . . .

Number of in-scope office locations

One ...............................................

More than one .........................................

Unknown.............................................

147,700

15,100

*1,100

5,400

1,200

300

90.1

9.2

0.7

0.8

0.8

0.2

Practice size2

Solo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Partner . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3–5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6–10 ...............................................

11 or more . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

113,600

18,700

23,600

6,200

1,800

4,900

1,400

1,000

400

200

69.4

11.4

14.4

3.8

1.1

1.1

0.8

0.7

0.3

0.1

Breadth of specialization

Solo or single-specialty group ................................

Multispecialty group ......................................

Unknown.............................................

147,500

14,600

*1,700

5,400

1,000

500

90.1

8.9

*1.0

0.7

0.6

0.3

Ownership3

Solo or partner practice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Group practice .........................................

HMO4...............................................

Other office setting5 ......................................

120,900

24,300

2,100

16,400

5,000

1,000

400

1,900

73.8

14.9

1.3

10.0

1.2

0.7

0.2

1.1

Participates in practice-based research network

Yes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

No . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Unknown.............................................

5,400

139,200

19,200

1,000

4,900

1,900

3.3

85.0

11.7

0.6

1.2

1.1

Geographic region

Northeast ............................................

Midwest .............................................

South . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

West ...............................................

36,300

30,100

60,700

36,600

2,300

2,000

3,500

3,000

22.2

18.4

37.1

22.4

1.3

1.2

1.7

1.6

Metropolitan status

MSA6 ...............................................

Non-MSA ............................................

144,600

19,200

5,500

2,800

88.3

11.7

1.6

1.6

. . . Category not applicable.

* Figure does not meet standards of reliability or precision.
 

1

See Appendix I for details on estimating practices. Practice estimates are rounded to the nearest hundred.
 

2

Practice size is number of physicians at practice location where most patients were seen. Practice size were randomly assigned for 1.6 percent of physicians missing this information.
 

3

Ownership of practice based on location where most patients were seen.
 

4

HMO is health maintenance organization.
 

5

Other setting includes ownership by community health centers, medical academic health center, other hospital, other health care corporation, other, or unknown.
 

6

MSA is metropolitan statistical area.
 
Page 12 [ Series 13, No. 166

Table 4. Percent distribution of office-based medical practices and percent distribution of physicians within practices, with corresponding

standard errrors, by use of electronic medical records and practice ownership: United States, 2005–2006

Practices2 Physicians within practices

Practice ownership1

Percent

distribution

of practices

Fully electronic

medical record

Part paper, part

electronic

medical record None3

Percent

distribution

of physicians

Fully electronic

medical record

Part paper, part

electronic

medical record None3

Percent distirbution

Total ............................ 100.0 9.2 12.7 78.2 100.0 12.8 13.7 73.5

Solo or partner practice. . . . . . . . . . . . . . . . . 100.0 7.1 11.4 81.5 100.0 7.5 11.4 81.1

Group practice ...................... 100.0 12.9 12.6 74.5 100.0 15.4 13.2 71.4

HMO4 ........................... 100.0 45.6 *17.7 *36.8 100.0 50.0 *20.9 29.1

Other office setting5 ................... 100.0 14.6 *21.0 64.4 100.0 14.9 20.6 64.5

Standard error of percent

Total ............................ . . . 0.9 1.2 1.3 . . . 0.9 1.0 1.2

Private solo or partner ................. . . . 1.0 1.3 1.5 . . . 1.0 1.2 1.4

Private group ....................... . . . 1.4 1.5 2.0 . . . 1.5 1.4 2.0

HMO4 ........................... . . . 8.9 5.9 8.7 . . . 7.4 5.5 7.0

Other office setting5 ................... . . . 3.5 5.6 6.0 . . . 2.3 3.3 4.0

* Figure does not meet standards of reliability or precision.
 

. . . Category not applicable.
 

1

Ownership of practice based on location where most patients were seen.
 

2

See Appendix I for details on estimating practices.
 

3

Includes unknowns.
 

4

HMO is health maintenance organization.
 

5

Other office settings includes ownership by community health center, medical academic health center, other hospital, other health care corporation, other, or unknown.
 

Table 5. Percentage of office-based medical practices and physicians within practices reporting selected features of their electronic medical

record system, with corresponding standard errors: United States, 2005–2006

All physicians All physicians

All medical within All medical within

Electronic medical record system feature practices1 practices2 practices practices

Percent Standard error of percent

Patient demographics ............................................ 19.2 23.7 1.3 1.2 
 

Physician clinical notes ........................................... 16.3 20.2 1.2 1.1 
 

Test results3 .................................................. 12.8 18.7 1.2 1.2 
 

Computerized orders for prescriptions .................................. 12.5 16.4 1.1 1.0 
 

Computerized orders for tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.4 14.4 1.1 1.0 
 

Public health reporting............................................ 4.9 6.0 0.7 0.6 
 

1

See Appendix I for details on estimating practices.
 

2

Includes nonfederal, office-based physicians who see patients in an office setting. Excludes radiologists, anesthesiologists, and pathologists.
 

3

Includes lab and imaging results.
 

NOTE: Percentages may be underestimates because electronic medical record use is unknown for 3.2 percent of physicians.
Series 13, No. 166 [ Page 13

Table 6. Percentage of office-based physicians by specialty type and physician accessibility, with corresponding standard errors:

United States, 2005–2006

Specialty type1 Specialty type1

All Primary All Primary

Physician accessibility specialties care Surgical Medical specialties care Surgical Medical

Percent of physicians Standard error of percent

Percentage of physicians accepting new

patients by payment source2

Any new patients ............................ 91.9 89.6 96.3 92.5 0.6 1.2 0.7 0.9

Self-pay ................................. 85.6 84.5 91.2 83.4 0.8 1.3 1.2 1.5

Medicare ................................. 77.9 71.1 90.9 80.2 0.9 1.5 1.3 1.6

Noncapitated private insurance ................... 75.5 76.6 78.8 71.2 1.2 1.7 1.9 2.0

Medicaid ................................. 65.5 64.4 74.2 61.0 1.2 1.9 2.2 2.0

Worker’s compensation ........................ 50.9 44.2 73.2 46.1 1.5 2.0 2.2 2.3

Capitated private insurance ..................... 49.3 55.0 45.8 41.8 1.8 2.3 2.6 2.4

No charge or charity .......................... 40.5 38.0 50.7 37.1 1.6 2.2 2.4 2.2

Percentage of physicians having difficulty referring patients

with selected payment sources for specialty consultation3

Medicaid ................................ 32.4 37.6 25.2 28.8 1.4 2.0 2.0 2.1

Medicare ................................. 9.3 10.9 6.4 8.8 0.8 1.1 1.1 1.4

Private insurance............................ 11.2 12.3 7.0 12.5 0.8 1.2 1.1 1.4

Uninsured ................................ 31.0 35.1 26.0 27.6 1.4 1.9 2.1 1.9

1

Specialty type is defined in Appendix I, Table V.
 

2

Information on accepting any new patients is missing for 2.5 percent of cases. The level of missing data for each type of new patient accepted ranged from 6 percent to 15 percent depending on type
 

of payment source.
 

3

Difficulty refers to the physician experiencing ‘‘some’’ or ‘‘a lot’’ of difficulty in referring patients with selected payment sources for specialty consultation in the last 12 months. The level of missing data
 

ranged from 7 percent to 11 percent depending on payment source of patient.
 

Table 7. Average number of weekly consultations reported during the last full week of practice, and percentage of physicians with selected

types of encounters by specialty type, with corresponding standard errors: United States, 2005–2006

Specialty type1 Specialty type1

All Primary All Primary

Type and volume of patient encounters specialties care Surgical Medical specialties care Surgical Medical

Average number of weekly visits2 Standard error

Volume of office visits last full week ....................... 73.4 85.3 67.1 57.3 1.2 2.0 1.8 1.9

Type of patient encounter4 Percent of physicians3

Hospital visits ..................................... 56.8 55.6 66.6 51.4 1.4 2.0 2.0 2.1 
 

Telephone consultation ............................... 50.7 57.2 41.5 46.3 1.6 2.1 2.6 2.2 
 

Home visits ...................................... 8.8 13.6 2.6 5.2 0.8 1.3 0.7 1.0 
 

E-mail or Internet consultation ........................... 6.0 6.3 5.7 5.9 0.7 0.9 1.3 1.2 
 

EMTALA mandated care5 .............................. 9.2 7.9 12.5 9.1 0.7 1.0 1.4 1.3 
 

Volume of patient encounters4 Average number of weekly consultations reported6

Hospital visits ..................................... 17.7 13.8 16.6 26.1 1.0 1.5 1.4 2.0 
 

Telephone consultation ............................... 17.4 20.7 9.9 15.5 0.8 1.2 0.7 1.4 
 

Home visits ...................................... 13.8 12.3 *17.0 *19.6 1.9 1.9 5.9 7.0 
 

E-mail or Internet consultation ........................... 10.1 11.2 9.1 *8.6 1.6 2.2 2.5 3.2 
 

Hours of EMTALA mandated care......................... 11.0 12.3 10.1 9.9 1.3 2.8 1.6 1.8 
 

* Figure does not meet standards of reliability or precision.
 

1

Specialty type is defined in Appendix I, Table V.
 

2

Average number of office visits during last full week of practice among physicians with any visits.
 

3

Percentage of physicians reporting any consultations during last full week of practice with any of that type of consultation.
 

4

Information on type of consultations was missing for 6 percent to 10 percent of physicians, depending on type of consultation.
 

5

EMTALA is care mandated by the Emergency Medical Treatment and Labor Act of 1986 (EMTALA).
 

6

Average number of consultations during last full week of practice for physicians reporting any of that type of consultation.
 
Page 14 [ Series 13, No. 166

Table 8. Average number of weekly consultations per physician during the last full week of practice, with corresponding standard errors, by

type of encounter and practice characteristics: United States, 2005–2006

Practice characteristic

Total

consultations1

Office

visits

Hospital

visits

Telephone

consultations

Total

consultations1

Office

visits

Hospital

visits

Telephone

consultations

Average number of weekly consultations reported2 Standard error

All office-based physicians ...................... 92.7 71.9 10.0 8.8 1.5 1.2 0.6 0.5

Specialty type3

Primary care. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Surgical .................................

Medical. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

105.6

81.6

78.4

83.7

65.5

56.2

7.7

11.0

13.4

11.8

4.1

7.2

2.5

2.3

2.5

2.0

1.8

1.8

0.9

1.0

1.1

0.8

0.4

0.8

Practice size

Solo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Partner . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3–5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6–10 ...................................

11 or more . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

90.1

90.4

95.0

96.0

93.4

70.2

72.0

74.1

74.5

68.0

8.9

8.3

11.4

11.6

10.4

9.2

8.6

7.9

8.3

11.3

2.7

4.1

2.7

4.0

4.8

2.2

3.7

2.1

2.6

3.2

0.8

1.1

1.1

2.8

1.7

0.8

1.2

0.8

1.1

2.0

Number of managed care contracts

None . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1–2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3–10 ...................................

More than 10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Unknown.................................

68.5

82.6

95.1

104.4

60.0

54.8

65.9

73.1

80.5

49.1

6.0

6.4

11.4

11.6

4.5

6.7

8.5

8.8

10.3

4.0

3.9

3.9

2.3

2.9

4.6

3.2

3.4

2.0

2.2

3.9

1.1

1.2

0.9

1.3

1.2

1.1

1.4

0.8

0.8

1.1

Ownership

Physician(s) ..............................

Health maintenance organization ..................

Other or unknown ...........................

96.0

78.0

76.3

74.1

61.9

61.5

10.9

2.6

6.4

9.1

11.0

6.8

1.7

6.6

3.4

1.3

5.4

2.9

0.7

0.7

0.9

0.6

2.3

0.9

Geographic region

Northeast ................................

Midwest .................................

South . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

West ...................................

92.6

98.8

96.7

80.9

68.5

75.9

76.5

64.3

9.0

12.2

11.6

6.6

13.0

8.5

7.1

8.1

3.5

2.8

2.9

2.6

2.5

2.1

2.4

2.0

1.1

1.4

1.3

0.8

1.4

1.1

0.7

0.9

Metropolitan status

MSA4 ...................................

Non-MSA ................................

92.1

97.3

71.4

76.3

10.1

9.2

8.8

9.5

1.6

4.4

1.3

3.5

0.7

1.2

0.5

1.6

1

Total consultations include patient encounters in the office, at the hospital, at home, over the telephone, and over the Internet.
 

2

Calculated across all office-based physicians, including those who reported zero values for any of these items.
 

3

Specialty type is defined in Appendix I, Table V.
 

4

MSA is metropolitan statistical area.
 
Series 13, No. 166 [ Page 15

Table 9. Average number of weekly consultations per physician during the last full week of practice, by type of encounter and physician

specialty, with corresponding standard errors: United States, 2005–2006

Total Office Hospital Telephone Total Office Hospital Telephone

Physician specialty1 consultations2 visits visits consultations consultations2 visits visits consultations

Average number of weekly consultations reported3 Standard error

All office-based physicians ................. 92.7 71.9 10.0 8.8 1.5 1.2 0.6 0.5

General or family practice.................. 106.5 86.4 5.0 12.4 3.6 2.9 0.6 1.3

Internal medicine ....................... 101.3 76.0 10.4 12.0 4.8 4.0 1.3 1.5

Pediatrics. . . . . . . . . . . . . . . . . . . . . . . . . . . . 112.3 93.9 4.8 11.8 5.6 4.5 0.5 1.5

General surgery........................ 67.0 41.4 21.1 3.8 5.5 2.9 3.7 0.5

Obstetrics and gynecology ................. 97.6 74.8 *12.4 9.8 6.4 3.1 4.9 1.9

Orthopedic surgery ...................... 92.9 76.2 10.5 4.7 4.3 3.4 1.1 1.1

Cardiovascular disease ................... 76.2 49.8 20.3 5.3 4.9 4.2 2.2 1.0

Dermatology .......................... 114.5 108.8 *1.3 4.1 7.4 6.9 0.6 0.9

Urology ............................. 89.8 72.6 9.8 7.1 4.0 3.7 0.9 1.0

Psychiatry ........................... 52.9 39.8 4.3 6.8 3.1 2.4 0.8 1.1

Neurology ........................... 67.9 45.9 13.5 7.9 3.5 2.5 1.7 1.3

Ophthalmology ........................ 101.3 94.6 1.4 4.0 5.3 5.0 0.3 0.8

Otolarnyngology........................ 92.6 82.1 4.4 5.3 4.5 4.3 0.5 0.7

Other .............................. 78.8 52.3 17.1 6.8 3.6 2.7 1.9 1.1

* Figure does not meet standards of reliability or precision.
 

1

Physician specialty is defined in Appendix I, Table IV.
 

2

Total consultations include patient encounters in the office, at the hospital, at home, over the telephone, and over the Internet.
 

3

Calculated across all office-based physicians, including those who reported zero values for any of these items.
 
Page 16 [ Series 13, No. 166

Appendix I
 

Technical Notes

Data Source

The data presented in this report are

from the 2005 and 2006 National

Ambulatory Medical Care Survey

(NAMCS), a national probability sample

survey of nonfederal office-based

physicians conducted by the Centers for

Disease Control and Prevention’s

National Center for Health Statistics

(NCHS), Division of Health Care

Statistics. The surveys were conducted

from December 27, 2004, through

December 24, 2006. The NAMCS data

collection is authorized under Section

308d of the Public Health Service Act

(Title 42, U.S. Code, section 306

[242k]). Participation is voluntary. In

April 2003, the Privacy Rule of the

Health Insurance Portability and

Accountability Act was implemented to

establish minimum federal standards for

safeguarding the privacy of individually

identifiable health information.

The target universe of NAMCS

includes nonfederally employed

physicians (excluding the specialties of

anesthesiology, radiology, and

pathology) who were classified by the

American Medical Association (AMA)

and the American Osteopathic

Association (AOA) as ‘‘office-based,

patient care.’’ Physicians in private,

nonhospital-based clinics and health

maintenance organizations were within

the scope of the survey, but those with

practices in federally operated facilities

and hospital-based outpatient

departments were not.

NAMCS utilizes a multistage

probability sample design involving

samples of 112 geographic primary

sampling units (PSUs) and physicians

within PSUs. PSUs are counties, groups

of counties, county equivalents (such as

parishes or independent cities), or towns

and townships (for some PSUs in New

England). A total sample of 6,350

physicians was selected from the master

files of AMA and AOA in 2005 and

2006. One should note that the 2006

NAMCS was enhanced by the inclusion

of 350 additional sample physicians;

150 were included to increase the

number of primary care physicians who

would be administered the 15-minute

Cervical Cancer Screening Supplement

during the induction interview, and

another 200 oncologists were included

to improve the precision of NAMCS

estimates in this specialty. Overall,

4,054 physicians were in scope (eligible

to participate) in the 2005 and 2006

surveys. Of these, 2,592 physicians

participated for an unweighted physician

response rate of 63.9 percent. The

physician universe, sample size, and

unweighted response rates for

2005–2006 by physician specialty are

shown in Table I.

Among sampled physicians,

63.8 percent were in scope at the time

of the survey and 36.2 percent were out

of scope. Sampled physicians were out

of scope for the following reasons: their

practice was hospital-based, they were

federally employed, they were in the

specialties of anesthesiology, pathology,

and radiology, or their practice was

nonoffice-based (institutional or

occupational) (18.6 percent); they were

retired or deceased (8.5 percent); they

were nonpracticing because their job

was nonclinical or they were

temporarily not practicing (e.g., on

sabbatical or on military detail)

(4.4 percent); or they were ineligible for

other reasons (4.6 percent) (data not

shown). Changes in work status for

sampled physicians could occur because

the time between creating the AMA and

AOA sample and the interview could

range from 3 to 18 months.

Additionally, the AMA surveys only

Table I. Average number of physicians in the universe, total sample, and sample response categories for the Physician Induction Interview,

and unweighted response rate, by physician stratum: National Ambulatory Medical Care Survey, 2005–2006

Sample

Out of In Participating Response rate

Physician stratum Universe1 Total scope scope Nonrespondents physicians (unweighted)2

Total ................................. 500,219 6,350 2,296 4,054 1,462 2,592 63.9

General and family practice ................... 70,683 684 231 453 161 292 64.5

Osteopathy ............................. 28,912 460 158 302 100 202 66.9

Internal medicine ......................... 75,545 415 184 231 81 150 64.9

Pediatrics .............................. 51,254 394 155 239 64 175 73.2

General surgery .......................... 19,969 406 173 233 75 158 67.8

Obstetrics and gynecology ................... 33,516 364 114 250 81 169 67.6

Orthopedic surgery ........................ 20,808 274 72 202 79 123 60.9

Cardiovascular diseases ..................... 16,954 416 114 302 125 177 58.6

Dermatology ............................ 8,648 234 54 180 62 118 65.6

Urology ............................... 8,683 306 83 223 78 145 65.0

Psychiatry.............................. 31,658 562 259 303 110 193 63.7

Neurology .............................. 10,182 504 196 308 135 173 56.2

Ophthalmology ........................... 15,827 252 58 194 69 125 64.4

Otolaryngology ........................... 8,006 294 83 211 77 134 63.5

All other specialties ........................ 99,577 785 362 423 165 258 61.0

1

Data are derived from the American Medical Association and the American Osteopathic Association and represent the average annual number of physicians who are designated as office-based
 

patient care for the 2005–2006 NAMCS.
 

2

Response rate is the number of participanting physicians divided by number of in-scope physicians.
 

NOTE: Participating physicians are those who took part in the 2005–2006 Physician Induction Interview.
 
Series 13, No. 166 [ Page 17

one-fourth of the AMA masterfile each

year to obtain updated information, and

response to their survey is low (21). As

a result, information on the masterfile

tends to be outdated.

The U.S. Census Bureau, acting as

the data collection agent for the survey,

provided training to field representatives

(FRs) throughout the United States. FRs

contacted physicians for induction into

the survey after an advance letter was

mailed by NCHS notifying the

physicians of their selection in the

survey. They also oversaw data

collection at physicians’ offices. The

induction interview was used to obtain

basic information about the practice

such as a physician’s employment status,

ownership of the practice, practice size,

and office type.

Estimation

In this report, estimates are

provided from two different sampling

weights; one for nonfederal office-based

physicians and one for medical

practices.

Physician practice estimates—

Estimates of physicians who see patients

in office settings are unbiased estimates

based on a complex sampling design

with multistage estimation. Physician

weights were used to estimate national

numbers and characteristics of

office-based physicians (e.g., sex, age,

specialty) and their practices (e.g.,

numbers of physicians in the practice,

single-specialty compared with

multispecialty practices, and types and

numbers of patient encounters in last

full week of practice). Information about

encounters from the last full week of

work is based on the respondent’s

memory rather than on records (see

Appendix II).

The NAMCS physician estimation

procedures have three basic components:

1) inflation by reciprocals of the

sampling selection probabilities, 2)

adjustment for physician nonresponse,

and 3) a calibration ratio adjustment

between the number of physicians in the

sample frame between the time the

sample was selected and the time that

the NAMCS data were collected. For

each physician, the sampling selection

probability reflects the probability of

PSU selection and selection of

physicians within each PSU. The

physician nonresponse adjustment factor

is the sample weight for responding

physicians augmented by a factor

accounting for the amount of

nonresponse by similar physicians.

Similar physicians were judged to be

physicians having the same specialty

designation and practicing in the same

PSU or region or metropolitan statistical

area (MSA) status. The calibration ratio

adjusts the number of physicians based

on the sample frame within specialty

stratum and region cells to reflect

universe counts provided by AMA and

AOA just prior to the NAMCS weights

being finalized. For example, the 2005

estimated number of physicians

increased from 281,600 to 317,100

physicians after calibration ratios were

applied. Similarly, the 2006 estimated

number of physicians increased from

292,800 to 300,700 physicians after

calibration ratios were applied.

Medical practice estimates—In this

report, the NAMCS physician sampling

weight is modified to produce a medical

practice estimator. Multiplicity occurs

within a sampling frame when a

member of the population is linked to

more than one entry on the frame, so

that the member has multiple chances of

being selected. In the NAMCS sampling

frame, multiplicity exists among

partnerships and group practices because

medical practices with more physicians

have a higher probability of being

selected than practices with fewer

physicians. Group practices are defined

as three or more physicians practicing

together with a common billing and

medical record system (22). No

sampling frame currently exists for

sampling all types of medical practices

(i.e., solo, partnership, and group).

Modifying a physician survey to make

estimates of medical practices has the

advantage of using a single survey and

arithmetic manipulations to estimate

both physicians and practices. In this

report, nationally representative

estimates of medical practices were

derived using a ‘‘multiplicity estimator’’

to account for multiplicity in the

physician frame (6).

The multiplicity measure used in

this calculation was based on physician

response to the question ‘‘How many

other physicians are associated with you

(at this location)?’’ This question was

asked for a maximum of four office

locations at which the sample physician

saw ambulatory patients during his or

her sampled week (see excerpts from

the 2005 and 2006 Physician Induction

Interview (PII) forms in Appendix II).

Practice size was assumed to be one

plus the number of other physicians

recorded at the location where most

patients were seen. Practice size was

missing for 1.6 percent of physicians.

For the purposes of this report, unknown

practice size was randomly assigned

according to physician specialty,

geographic region, and employment

information from the sampling frames.

About 12.9 percent of physicians

reported that they saw patients at

multiple office locations. Medical

practices were estimated by adjusting

the physician sample weight by the

inverse of the multiplicity indicator

(number of physicians in the practice) to

account for the increased likelihood of

selection:

(Medical practice weight)ij =

(Physician sample weight)ij /Sij,

where Sij equals the number of

physicians within the practice j reported

by the physician i

.

Tests of Significance

In this report, the determination of

statistical inference is based on a

two-tailed t-test. The Bonferroni

inequality was used to establish the

critical value for statistically significant

differences (0.05 level of significance)

based on the number of possible

comparisons within a particular variable

(or combination of variables) of interest.

A weighted least-squares regression

analysis was used to determine the

significance of trends at the 0.05 level.

Sampling and Nonsampling

Errors

The standard error is primarily a

measure of the sampling variability that

occurs by chance when only a sample,
Page 18 [ Series 13, No. 166

rather than an entire universe, is

surveyed. The standard error does not

measure any systematic biases in the

data. The standard errors presented in

the tables and used in tests of

significance for this report were

estimated using SUDAAN software.

SUDAAN computes standard errors by

using a first-order Taylor approximation

of the deviation of estimates from their

expected values. A description of the

software and the approach it uses has

been published (7).

As in any survey, results are subject

to both sampling and nonsampling

errors. Nonsampling errors include

reporting and processing errors as well

as biases due to nonresponse and

incomplete response. The magnitude of

the nonsampling errors cannot be

computed. However, these errors were

kept to a minimum by procedures built

into the operation of the survey. To

eliminate ambiguities and encourage

uniform reporting, attention was given

to the phrasing of items, terms, and

definitions. Also, pretesting of most data

items and survey procedures was

performed. Quality control procedures

and consistency and edit checks reduced

errors in data coding and processing.

The weighted response rate for

physicians participating in the

2005–2006 NAMCS PII was

65.5 percent. Table II presents weighted

characteristics of NAMCS respondents

and nonrespondents, along with

weighted response rates. (One should

note that for the purposes of presenting

physician specialty in Table II, the

stratum of 200 oncologists included in

the 2006 NAMCS was moved to the

stratum in which they would have been

sampled for 2005.) Distributions were

similar, with the following exceptions:

physicians who were female, physicians

who worked in non-MSAs,

pediatricians, and physicians working in

faculty practices were more likely to

cooperate. Although some response

variation by physician specialty may

have been increased by redistributing

oncologists to their original sample

stratum, the nonresponse adjustment

takes MSA status and specialty into

account. However, the higher response

by female physicians may bias

characteristics for which females vary

Table II. Characteristics of the 2005–2006 National Ambulatory Medical Care Survey

physician respondents and nonrespondents to the Physician Induction Interview

Total

Number of sample Responding Nonresponding

sampled percent physician physician Weighted

in-scope distribution3 distribution4 distribution5 response

Physician characteristic1 physicians2 (weighted) (weighted) (weighted) rate6

All office-based physicians ....... 4,054 100.0 100.0 100.0 0.655
 

Age
 

Under 35 years .............. 179 5.2 5.3 5.0 0.665 
 

35–44 years ................ 1,056 27.6 27.8 27.3 0.660 
 

45–54 years ................ 1,372 33.5 33.7 33.2 0.659 
 

55–64 years ................ 1,037 24.4 24.7 23.7 0.665 
 

65 years and over............. 410 9.3 8.4 10.8 0.597 
 

Sex7

Male . . . . . . . . . . . . . . . . . . . . . 3,223 76.5 75.1 79.2 0.643 
 

Female ................... 831 23.5 24.9 20.8 0.694 
 

Region
 

Northeast .................. 901 20.8 21.1 20.2 0.664 
 

Midwest . . . . . . . . . . . . . . . . . . . 862 20.7 20.9 20.3 0.661 
 

South .................... 1,358 35.7 36.0 35.1 0.661 
 

West . . . . . . . . . . . . . . . . . . . . . 933 22.8 22.0 24.3 0.632 
 

Metropolitan status7

MSA8 .................... 3,651 89.3 87.7 92.2 0.644

Non-MSA . . . . . . . . . . . . . . . . . . 403 10.7 12.3 7.8 0.750

Physician specialty7,9

General or family practice ........ 619 18.6 18.4 18.9 0.648 
 

Internal medicine ............. 248 14.4 14.1 14.8 0.644 
 

Pediatrics . . . . . . . . . . . . . . . . . . 249 10.0 11.3 7.7 0.735 
 

General surgery .............. 218 3.6 3.7 3.4 0.678 
 

Obstetrics and gynecology ....... 268 7.7 8.0 7.0 0.686 
 

Orthopedic surgery ............ 218 4.8 4.6 5.3 0.624 
 

Cardiovascular diseases ......... 310 4.3 3.9 4.9 0.601 
 

Dermatology ................ 186 2.3 2.3 2.3 0.661 
 

Urology ................... 225 2.1 2.1 2.1 0.664 
 

Psychiatry.................. 310 5.7 5.6 6.1 0.636 
 

Neurology . . . . . . . . . . . . . . . . . . 306 2.1 1.8 2.6 0.560 
 

Opthalmology ............... 205 4.2 4.0 4.5 0.628 
 

Otolaryngology ............... 209 1.9 1.9 1.9 0.651 
 

All other specialties ............ 483 18.4 18.3 18.5 0.652 
 

Specialty type9

Primary care . . . . . . . . . . . . . . . . 1,361 50.1 51.1 48.2 0.668

Surgical . . . . . . . . . . . . . . . . . . . 1,196 21.8 21.0 23.2 0.633

Medical ................... 1,497 28.1 27.9 28.7 0.649

Practice type7

Solo ..................... 1,099 26.3 24.8 29.2 0.617

Two physicans ............... 247 6.3 6.2 6.6 0.642

Group or HMO10.............. 1,715 41.0 42.4 38.4 0.677

Medical school or government ..... 67 1.6 2.0 0.8 0.829

Other. . . . . . . . . . . . . . . . . . . . . 63 1.4 1.6 1.0 0.746

Unclassified................. 863 23.3 23.0 24.0 0.645

1

Characteristic information is from the master files of the American Medical Association and the American Osteopathic Association.
 

2

In-scope physicians are those who verified that they were nonfederal and involved in direct patient care in an office-based setting,
 

excluding the specialties of radiology, pathology, and anesthesiology.
 

3

Total physicians are those who were selected from the master files of the American Medical Association and the American
 

Osteopathic Association (n = 6,350).
 

4

Responding physicians are those who were in-scope and responded to the National Ambulatory Medical Care Survey (NAMCS)
 

Physician Induction Interview (PII).
 

5

Nonresponding physicians are those who were in scope and refused to respond to the NAMCS PII.
 

6

Numerator is the number of in-scope physicians who responded to the NAMCS PII. Denominator is all in-scope sampled
 

physicians.
 

7

Chi-square test of association is significant at p < 0.05.
 

8

MSA is metropolitan statistical area.
 

9

Physician specialty and specialty type are defined in the ‘‘Physician specialty groups’’ section of Appendix I.
 

10HMO is health maintenance organization.
 
Series 13, No. 166 [ Page 19

Table III. Weighted item nonresponse rates for 2005–2006 report variables Use of Tables

Weighted

item

Variable nonresponse

Race and ethnicity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25.4 
 

Graduate of foreign medical school ........................ 6.2 
 

Practice size ..................................... 1.6 
 

Practice-based research network ......................... 13.7
 

Electronic medical record .............................. 3.2 
 

Patient demographic information ........................ 3.2
 

Computerized prescription order entry..................... 4.0 
 

Computerized test order entry. . . . . . . . . . . . . . . . . . . . . . . . . . 4.3 
 

Test results ..................................... 3.5 
 

Clinical notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2 
 

Public health reporting .............................. 20.0
 

Number of managed care contracts ....................... 5.8
 

Percent revenue from managed care contracts ................ 25.7
 

Percent revenue from private insurance ..................... 10.8
 

Percent revenue from Medicare .......................... 11.0
 

Percent revenue from Medicaid .......................... 12.0
 

Percent revenue from other sources ....................... 15.3 
 

Any new patients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 
 

New self-pay patients accepted .......................... 5.7
 

New Medicare patients accepted ......................... 5.8
 

New noncapitated private insurance patients accepted ........... 12.1 
 

New Medicaid patients accepted ......................... 6.2
 

New worker’s compensation patients accepted................. 8.1 
 

New capitated private insurance patients accepted .............. 11.8
 

New no charge or charity patients accepted .................. 14.7 
 

Difficulty referring Medicaid patients ....................... 7.6 
 

Difficulty referring Medicare patients . . . . . . . . . . . . . . . . . . . . . . . 7.7 
 

Difficulty referring private insurance patients .................. 7.1
 

Difficulty referring uninsured patients ....................... 10.5 
 

Volume of office visits last full week ....................... 1.2 
 

Weekly hospital visits ................................ 10.0
 

Weekly telephone consultations .......................... 9.8
 

Weekly home visits.................................. 5.8 
 

Weekly e-mail or Internet consultations ..................... 9.1
 

Hours of EMTALA mandated care per week1 .................. 7.7 
 

1

EMTALA is care mandated by the Emergency Medical Treatment and Labor Act of 1986 (EMTALA).

with male physicians, such as average

number of weekly patient encounters.

Item nonresponse rates in the

NAMCS PII varied considerably. Most

nonresponse occurs when the needed

information is unknown or unavailable

to the respondent or the respondent

refuses to answer the item. Nonresponse

can also result when the information is

available, but survey procedures are not

followed and the item is left blank (i.e.,

interviewer did not follow the correct

skip pattern). In this report, the majority

of estimates presented include a

combined entry of ‘‘unknown’’ and

‘‘blank’’ to display missing data.

Estimates based on categorical responses

will generally include the missing cases

in the denominator. Table III presents

information on item nonresponse for

variables presented in this report.

Estimates based on numeric entries,

such as volume of encounters during the

last full week of practice, were an

exception to this rule, because computed

estimates exclude cases with missing

data. If nonresponse is random, the

observed distribution for the reported

item (i.e., excluding cases for which the

information is unknown) would be close

to the true distribution. However, if

nonresponse is not random, the observed

distribution could vary significantly

from the actual distribution. Researchers

need to decide how best to treat items

with high levels of missing responses.

For items with a nonresponse greater

than 50 percent, data are not presented.

Estimates are not presented unless a

reasonable assumption regarding their

probability distributions is possible on

the basis of the Central Limit Theorem.

This theorem states that given a

sufficiently large sample size, the

sample estimate approximates the

population estimate, and, upon repeated

sampling, its distribution would be

approximately normal.

In this report, estimates are not

presented if they are based on fewer

than 20 cases in the sample data—only

an asterisk (*) appears in the tables. The

relative standard error (RSE) of an

estimate is obtained by dividing the

standard error by the estimate itself. The

result is then expressed as a percentage

of the estimate. Estimates based on

20–29 cases are also presented with

asterisks (*) regardless of the RSE level.

Estimates based on 30 or more cases

include an asterisk (*) only if the RSE

of the estimate exceeds 30 percent.

In the tables, estimates of

office-based physicians have been

rounded to the nearest hundred.

Consequently, estimates will not always

add to totals. Rates and percentages

were calculated from original unrounded

figures and do not necessarily agree

with figures calculated from rounded

data.

Physician Specialty Groups

This report classifies specific

physician specialties into two general

categorical schemes: physician specialty

and type of specialty. The NAMCS

design groups physicians into 15 strata,

or specialty groups, for sampling

purposes. One stratum, doctors of

osteopathy, was based on information

from the AOA. The ‘‘physician

specialty’’ classification includes the

same strata as used for sampling

purposes with the exception of the

doctors of osteopathy stratum, which is

combined with doctors of medicine in

the following 14 categories: general and

family practice, internal medicine,

pediatrics, general surgery, obstetrics

and gynecology, orthopedic surgery,

cardiovascular diseases, dermatology,

urology, psychiatry, neurology,
Page 20 [ Series 13, No. 166

ophthalmology, otolaryngology, and a

residual category of other specialties.

The physician specialty classification is

created using updated information from

AMA, as well as information provided

by sampled physicians. Specific

physician specialties in each of the 14

categories are defined in Table IV.

In this classification, a pediatric

cardiothoracic physician, for example, is

grouped with other pediatricians. On the

other hand, the ‘‘specialty type’’

classification divides AMA specialties

into three major categories—primary

care, surgical specialties, and medical

specialties—and puts more emphasis on

specialization type. For example,

pediatric cardiothoracic physicians are

classified as a surgical specialty in this

classification. The specific physician

specialties included in each of the three

specialty types are provided in Table V.

Table IV. Reclassification of physician specialty based on American Medical Association

subspecialty designations for use with National Ambulatory Medical Care Survey

Physician specialty Subspecialty designation

General practice .............. FP—Family practice

FPG—Geriatric medicine (family practice)

FSM—Sports medicine (family practice)

GP—General practice

Internal medicine ............. IM—Internal medicine

Pediatrics .................. ADL—Adolescent medicine (pediatrics)

CCP—Pediatric critical care medicine

DBP—Developmental-behavioral pediatrics

MPDI—Internal medicine/pediatrics

NDN—Neurodevelopmental disabilities (psychiatry and neurology)

NDP—Neurodevelopmental disabilities (pediatrics)

NPM—Neonatal-perinatal medicine

PD—Pediatrics

PDA—Pediatric allergy

PDC—Pediatric cardiology

PDE—Pediatric endocrinology

PDI—Pediatric infectious diseases

PDP—Pediatric pulmonology

PDT—Medical toxicology (pediatrics)

PEM—Pediatric emergency medicine (pediatrics)

PG—Pediatric gastroenterology

PHO—Pediatric hematology/oncology

PN—Pediatric nephrology

PPR—Pediatric rheumatology

PSM—Sports medicine (pediatrics)

General surgery .............. GS—General surgery

Obstetrics and gynecology ....... GO—Gynecological oncology

GYN—Gynecology

MFM—Maternal and fetal medicine

OBG—Obstetrics and gynecology

OBS—Obstetrics

OCC—Critical care medicine (obstetrics and gynecology)

REN—Reproductive endocrinology

Orthopedic surgery ............ OAR—Adult reconstructive orthopedics

OFA—Foot and ankle, orthopedics

OMO—Musculoskeletal oncology

OP—Pediatric orthopedics

ORS—Orthopedic surgery

OSM—Sports medicine (orthopedic surgery)

OSS—Orthopedic surgery of the spine

OTR—Orthopedic trauma

Cardiovascular diseases ......... CD—Cardiovascular disease

Dermatology ................ D—Dermatology

Urology ................... U—Urology

UP—Pediatric urology

Psychiatry ................. ADP—Addiction psychiatry

CHP—Child and adolescent psychiatry

NUP—Neuropsychiatry

P—Psychiatry

PFP—Forensic psychiatry

PYA—Psychoanalysis

PYG—Geriatric psychiatry

PYM—Psychosomatic medicine

Neurology .................. CHN—Child neurology

CN—Clinical neurophysiology

ESN—Endovascular surgical neuroradiology

N—Neurology

NRN—Neurology/diagnostic radiology/neuroradiology

VN—Vascular neurology

Ophthalmology ............... OPH—Ophthalmology

PO—Pediatric ophthalmology

Otolaryngology .............. NO—Otology/neurotology

OTO—Otolaryngology

PDO—Pediatric otolaryngology

All other ................... A—Allergy ADM—Addiction medicine

AI—Allergy and immunology

ALI—Clinical and laboratory immunology (allergy and immunology)

AM—Aerospace medicine

AMI—Adolescent medicine (internal medicine)

AS—Abdominal surgery

CBG—Clinical biochemical genetics

CCG—Clinical cytogenetics

CCM—Critical care medicine (internal medicine)

CCS—Surgical critical care (surgery)

CFS—Craniofacial surgery

CG—Clinical genetics

CMG—Clinical molecular genetics
Series 13, No. 166 [ Page 21

Table IV. Reclassification of physician specialty based on American Medical Association

subspecialty designations for use with National Ambulatory Medical Care Survey—Con.

Physician specialty Subspecialty designation

All other . . . . . . . . . . . . . . . . . . . CRS—Colon and rectal surgery
 

CS—Cosmetic surgery

DDL—Clinical and laboratory dermatological immunology

DIA—Diabetes

DS—Dermatologic surgery

EM—Emergency medicine

END—Endocrinology, diabetes and metabolism

EP—Epidemiology

ESM—Sports medicine (emergency medicine)

ETX—Medical toxicology (emergency medicine)

FPS—Facial plastic surgery

GE—Gastroenterology

GPM—General preventive medicine

HEM—Hematology (internal medicine)

HEP—Hepatology

HNS—Head and neck surgery

HO—Hematology/oncology

HS—Hand surgery

IC—Interventional cardiology

ICE—Clinical cardiac electrophysiology

ID—Infectious diseases

IG—Immunology

ILI—Clinical and laboratory immunology (internal medicine)

IMG—Geriatric medicine (internal medicine)

ISM—Sports medicine (internal medicine)

LM—Legal medicine

MDM—Medical management

MG—Medical genetics

NC—Nuclear cardiology

NEP—Nephrology

NS—Neurological surgery

NSP—Pediatric surgery (neurology)

NTR—Nutrition

OM—Occupational medicine

OMF—Oral and maxillofacial surgery

OMM—Osteopathic manipulative medicine

ON—Medical oncology

PA—Clinical pharmacology

PCC—Pulmonary critical care medicine

PCS—Pediatric cardiothoracic surgery

PDS—Pediatric surgery (surgery)

PE—Pediatric emergency medicine (emergency medicine)

PHL—Phlebology

PHM—Pharmaceutical medicine

PHP—Public health and general preventive medicine

PLI—Clinical and laboratory immunology (pediatrics)

PLM—Palliative medicine

PM—Physical medicine and rehabilitation

PMD—Pain medicine

PMM—Sports medicine (physical medicine and rehabilitation)

PPN—Pain medicine (psychiatry)

PRD—Procedural dermatology

PS—Plastic surgery

PSH—Plastic surgery within the head and neck

PTX—Medical toxicology (preventive medicine)

PUD—Pulmonary diseases

RHU—Rheumatology

RPM—Pediatric rehabilitation medicine

SCI—Spinal cord injury medicine

SME—Sleep medicine

SO—Surgical oncology

TRS—Traumatic surgery

TS—Thoracic surgery

TTS—Transplant surgery

UCM—Urgent care medicine

UM—Underseas medicine (preventive)

VM—Vascular medicine

VS—Vascular surgery

OS—Other specialty

US—Unspecified specialty
Page 22 [ Series 13, No. 166

Table V. Reclassification of physician specialty into specialty type for use with National

Ambulatory Medical Care Survey data

Physician specialty	 Subspecialty designation

Primary care specialties ......... 	 AMI—Adolescent medicine (internal medicine)

ADL—Adolescent medicine (pediatrics)

FP—Family practice

GP—General practice

FPG—Geriatric medicine (family practice)

IMG—Geriatric medicine (internal medicine)

GYN—Gynecology

IM—Internal medicine

MPD—Internal medicine/pediatrics

MFM—Maternal and fetal medicine

OBS—Obstetrics

OBG—Obstetrics and gynecology

PD—Pediatrics

FSM—Sports medicine (family practice)

ISM—Sports medicine (internal medicine)

PSM—Sports medicine (pediatrics)

Surgical specialties ............ 	 AS—Abdominal surgery

OAR—Adult reconstructive orthopedics

CRS—Colon and rectal surgery

CS—Cosmetic surgery

CFS—Craniofacial surgery

OCC—Critical care medicine (obstetrics and gynecology)

DS—Dermatologic surgery

ESN—Endovascular surgical neuroradiology

FPS—Facial plastic surgery

OFA—Foot and ankle, orthopedics

GS—General surgery

GO—Gynecological oncology

HS—Hand surgery

HNS—Head and neck surgery

OMO—Musculoskeletal oncology

NS—Neurological surgery

OPH—Ophthalmology

OMF—Oral and maxillofacial surgery

ORS—Orthopedic surgery

OSS—Orthopedic surgery of the spine

OTR—Orthopedic trauma

OTO—Otolaryngology

NO—Otology/neurotology

PCS—Pediatric cardiothoracic surgery

PO—Pediatric ophthalmology

OP—Pediatric orthopedics

PDO—Pediatric otolaryngology

NSP—Pediatric surgery (neurology)

PDS—Pediatric surgery (surgery)

UP—Pediatric urology

PS—Plastic surgery

PSH—Plastic surgery within the head and neck

PRD—Procedural dermatology

OSM—Sports medicine (orthopedic surgery)

CCS—Surgical critical care (surgery)

SO—Surgical oncology

TS—Thoracic surgery

TTS—Transplant surgery

TRS—Traumatic surgery

U—Urology

VS—Vascular surgery

Medical specialties ............ 	 ADM—Addiction medicine

ADP—Addiction psychiatry

AM—Aerospace medicine

A—Allergy

AI— Allergy and immunology

CD—Cardiovascular diseases

CHP—Child and adolescent psychiatry

CHN—Child neurology

DDL—Clinical and laboratory dermatological immunology

ILI—Clinical and laboratory immunology (internal medicine)

PLI — Clinical and laboratory immunology (pediatrics)

CBG—Clinical biochemical genetics

ICE —Clinical cardiac electrophysiology

CCG—Clinical cytogenetics

CG—Clinical genetics

ALI—Clinical laboratory immunology (allergy and immunology)

CMG —Clinical molecular genetics

CN—Clinical neurophysiology

PA—Clinical pharmacology

CCM —Critical care medicine (internal medicine)

D—Dermatology

DBP—Developmental-behavioral pediatrics

DIA—Diabetes
Series 13, No. 166 [ Page 23

Table V. Reclassification of physician specialty into specialty type for use with National

Ambulatory Medical Care Survey data—Con.

Physician specialty Subspecialty designation

Medical specialties ............ EM—Emergency medicine
 

END—Endocrinology, diabetes and metabolism

EP—Epidemiology

PFP—Forensic psychiatry

GE—Gastroenterology

GPM—General preventive medicine

PYG—Geriatric psychiatry

HEM—Hematology (internal medicine)

HO—Hematology/oncology

HEP—Hepatology

IG—Immunology

ID—Infectious diseases

IC—Interventional cardiology

LM—Legal medicine

MG—Medical genetics

MDM—Medical management

ON—Medical oncology

ETX—Medical toxicology (emergency medicine)

PDT—Medical toxicology (pediatrics)

PTX—Medical toxicology (preventive medicine)

NPM—Neonatal-perinatal medicine

NEP—Nephrology

NDP—Neurodevelopmental disabilities (pediatrics)

NDN—Neurodevelopmental disabilities (psychiatry and neurology)

N—Neurology

NRN—Neurology/diagnostic radiology/neuroradiology

NUP—Neuropsychiatry

NC—Nuclear cardiology

NTR—Nutrition

OM—Occupational medicine

OMM—Osteopathic manipulative medicine

PMD—Pain medicine

PPN—Pain medicine (psychiatry)

PLM—Palliative medicine

PDA—Pediatric allergy

PDC—Pediatric cardiology

CCP—Pediatric critical care medicine

PE—Pediatric emergency medicine (emergency medicine)

PEM—Pediatric emergency medicine (pediatrics)

PDE—Pediatric endocrinology

PG—Pediatric gastroenterology

PHO—Pediatric hematology/oncology

PDI— Pediatric infectious diseases

PN—Pediatric nephrology

PDP—Pediatric pulmonology

RPM —Pediatric rehabilitation medicine

PPR—Pediatric rheumatology

PHM—Pharmaceutical medicine

PHL—Phlebology

PM—Physical medicine and rehabilitation

P—Psychiatry

PYA —Psychoanalysis

PYM—Psychosomatic medicine

PHP—Public health and general preventive medicine

PCC—Pulmonary critical care medicine

PUD—Pulmonary diseases

REN—Reproductive endocrinology

RHU—Rheumatology

SME—Sleep medicine

SCI— Spinal cord injury medicine

ESM—Sports medicine (emergency medicine)

PMM—Sports medicine (physical medicine and rehabilitation)

UM—Underseas medicine (preventive medicine)

UCM—Urgent care medicine

VM—Vascular medicine

VN—Vascular neurology

OS—Other specialty

US—Unspecified specialty
Page 24 [ Series 13, No. 166

Appendix II
 

Excerpts from the 2005 Physician Induction Interview Form

Ask item 17a ONCE to obtain total for ALL in-scope locations. 

do you expect to see any ambulatory patients? (Only include days at in-scope locations.) 

17a. 

Edit Note: If physician is unavailable or refuses to participate,

enter number of days in a normal week. 

#1 #2 #3 #4 

Office location No. 

Enter street name or town of in-scope location(s). 

NOTE: Keep the location numbers the same as the office numbers in item 16a. 

During your last normal week of practice,

approximately how many office visit encounters

did you have at each office location? 

Note: If physician is in group practice, only

include the visits to sampled physician. 

Number 

of visits _____ _____ _____ _____ Edit 

During the week of Monday, ____________ through 

Sunday ____________, do you expect to see about 

c. 

_____ _____ _____ _____ 

Estimated Number 

of Days 

Section II – INDUCTION INTERVIEW – Continued 

b. 

the same number of visits as you saw during your

last normal week in each office taking into account

time off, holidays, and conferences? 

Note: Mark (X) response. If answer is "Yes", SKIP item 17d for

that particular office location. If answer is "No", then ASK item

17d for that office location. 

1 1 

No . . . 2 2 

1 

2 

1 

2 

Yes . . . 

Approximately how many ambulatory visits do

you expect to have at this office location? 

d. 

Tally of estimated number of visits 

NOTE: To obtain the total number of estimated visits use 

estimate from item 17b if "Yes" was marked in item 17c. If 

"No" was marked in item 17c use the estimate from item 

17d. 

e. 

_____ 

If physician is unavailable or refuses to participate,

enter number of visits in normal week. 

NOTES 

Number 

of visits 

Number of visits 

During the week of Monday, ____________ through Sunday, ___________ How many days 

FORM NAMCS-1 (11-17-2004) Page 9
 
Series 13, No. 166 [ Page 25
 

Section II – INDUCTION INTERVIEW – Continued 

During your last normal week of practice, about 

how many encounters of the following type did you 

make with patients: 

20a. Number of encounters 

per week 

(1) Home visits (including nursing homes) 

(2) Hospital visits . ............................. 

(3) Telephone consults ......................... 

(4) Internet/e-mail consults ..................... 

......... 

The following question is concerned with the Emergency 

Medical Treatment and Labor Act of 1986 (EMTALA). 

b. In a typical week, how many hours do you spend 

providing EMTALA mandated care? 

PROBE – We are interested in all hours spent 

screening and stabilizing patients, regardless 

of whether you were compensated for them. 

Number of hours 

Do you have a solo practice, or are you associated 

with other physicians in a partnership, in a group 

practice, or in some other way (at this/that in-scope 

location)? Nonsolo .......... 

How many other physicians are associated with 

you (at this/that in-scope location)? 

How many 

Is this a single- or multi-specialty group practice 

(at this/that in-scope location)? 

If "Owner" is marked then automatically mark "Physician or 

physician group" in item 18e. 

Employee ........ 

Contractor ........ 

Who owns the practice (at this/that in-scope location)? Physician or 

physician group . . . . . 

Other hospital ..... 

Other health 

care corp ........ 

Other – Specify for 

18a. 

Now, I’m going to ask about your practice at 

(in-scope location). Solo . . . . . . . . . . . . 1 1 1 1 

2 

b. 

c. 

2 2 2 

_____ _____ _____ _____ 

Owner .......... 

2 2 2 2 

3 3 3 3 

1 1 1 

e. 

1 1 1 1 

2 2 2 2 

3 3 3 3 

5 5 5 5 

6 6 6 6 

Location #1 

Location #2 

Office Location #1 #2 #3 #4 

Location #4 

Location #3 

1 1 

Single ........... 2 2 

1 

2 

1 

2 

Are you a full- or part-owner, employee, or an 

independent contractor (at this/that in-scope location)? 

d. 

Medical/ Academic 

health center ...... 

HMO . . . . . . . . . . . 

4 4 4 4 

If Solo, SKIP to item 18d. 

1 

Multi . ........... 

Is any laboratory testing performed in the office 

(at this/that in-scope location)? 

19. Yes . . . . . . . . . . . . 1 1 1 1 

No . . . . . . . . . . . . . 2 2 2 2 

RETURN TO ITEM 18a FOR NEXT IN-SCOPE LOCATION 

Page 10 FORM NAMCS-1 (11-17-2004) 
Page 26 [ Series 13, No. 166

FORM NAMCS-1 (11-17-2004) Page 11 

Section II – INDUCTION INTERVIEW – Continued 

I would like to ask a few questions about your 

practice revenue and contracts with managed care 

plans. 

Roughly, what percent of your practice revenue 

from patient care comes from – 

24a. Percent of practice 

revenue 

(1) Medicare? . . ................................. 

(2) Medicaid? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

(3) Private insurance? . . . . . . . . . .................. 

(4) Other? – (including charity, research, CHAMPUS, VA, etc.) 

Ask items 24 and 25 ONCE for ALL in-scope locations. 

% 

% 

% 

% 

FR NOTE – Categories should sum close 

to 100%. 

NOTES 

Does your practice use electronic MEDICAL 

RECORDS (not including billing records)? 

23a. 1 

2 

3 

4 

Yes, all electronic 

No 

Don’t know 

Does your practice submit claims electronically? 

(Electronic billing) 

1 

2 

3 

Yes 

No 

Don’t know 

Are you a member of a practice-based 

research network (PBRN)? 

21. 1 

2 

3 

Yes 

No 

Don’t know 

22. 

SKIP to item 24a 

Yes, part paper and part electronic 

b. Does your practice’s electronic medical 

record system include – 

seY nwonknU

(1) Patient demographic information? 1 2 3 

(2) Computerized orders for prescriptions? 1 2 3 

(3) Computerized orders for tests? 1 2 3 

(4) Test results? 1 2 3 

(5) Nurses’ notes? 1 2 3 

(6) Physicians’ notes? 1 2 3 

(7) Reminders for guideline-based 

interventions and/or screening tests? 1 2 3 

(8) Public health reporting? 1 2 3 

No 
Series 13, No. 166 [ Page 27
 

Section II – INDUCTION INTERVIEW – Continued 

Are you currently accepting "new" patients into your 

practice(s)(at in-scope locations)? 

From those "new" patients, which of the following 

types of payment do you accept (at in-scope locations)? 

(1) Private insurance – 

25a. Yes 

No – SKIP to item 26 

Don’t know – SKIP to item 26 

1 

2 

3 

b. 

(2) Medicare 

(3) Medicaid 

(4) Workers compensation? 

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

. . . . . . . . . . . . . . . . . . . . . . . . . . . 

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

(5) Self-pay? . . . . . . . . . . . . . . . . . . . ................ 

....................... 

(6) No charge? . . . . . . . . . . ........................ 

1 Yes 2 No 3 Don’t know

1 Yes 2 No Don’t know 

1 Yes 2 No Don’t know 

1 Yes 2 No Don’t know 

1 Yes 2 No Don’t know 

1 Yes 2 No Don’t know 

3 

3 

3 

3 

3 

(a) Capitated? 

(b) Non-capitated? 

1 Yes 2 No 3 Don’t know

On a 4-point scale from a lot of difficulty, some, little, 

or no difficulty, in the last 12 months, has your 

practice experienced any difficulty in referring 

patients with the following types of health insurance 

for specialty consultations? 

26. 

(a) Medicaid 

(b) Medicare 

(c) Private insurance ........................... 

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

(d) Uninsured . . ................................ 

Little 

difficulty 

Don’t 

know 

No 

difficulty 

1 2 3 4 5 

1 

1 

1 

2 3 4 5 

2 3 4 5 

2 3 4 5 

6 

6 

6 

6 

A lot of 

difficulty 

Some 

difficulty 

Not 

Applicable 

24b. Roughly, how many managed care contracts does 

this practice have such as HMOs, PPOs, IPAs, and 

point-of-service plans? 

FR NOTE – 

If necessary read: 

c. Roughly, what percentage of the patient care 

revenue received by this practice comes from 

(these) managed care contracts? 

Edit 

Percent of revenue from 

managed care 

% 

None – SKIP to item 25a. 

Less than 3 

3 to 10 

More than 10 

1 

2 

3 

4 

Managed care includes any type of 

group health plan using financial 

incentives or specific controls to 

encourage utilization of specific 

providers associated with the plan. 

Include Medicare managed care and Medicaid 

managed care, but not traditional Medicare and 

Medicaid. Include any private insurance managed 

care plans. Be sure the response is about contracts and not patients. 

Include all the different plans an insurance provider may have and for which the physician has a 

contract. For example, the physician may have a 

contract for each of the plans Aetna may offer: a 

PPO, IPA, and point-of-service plan. This would 

equal 3 contracts, not 1 contract. It may be 

necessary to obtain information from the billing 

office of the practice. 

Page 12 FORM NAMCS-1 (11-17-2004) 
Excerpts from the 2006 Physician Induction Interview Form

 

 

 

 

Ask item 17a ONCE to obtain total for ALL in-scope locations. 

During the week of Monday, ____________ through Sunday, ___________ How many days 

do you expect to see any ambulatory patients? (Only include days at in-scope locations.) 

17a. 

Edit Note: If physician is unavailable or refuses to participate, 

enter number of days in a normal week. 

#1 #2 #3 #4 

Office location No. 

Enter street name or town of in-scope location(s). 

NOTE: Keep the location numbers the same as the office numbers in item 16a. 

During your last normal week of practice, 

approximately how many office visit encounters 

did you have at each office location? 

Note: If physician is in group practice, only 

include the visits to sampled physician. 

Number 

of visits 

Edit 

During the week of Monday, ____________ through 

Sunday ____________, do you expect to see about 

c. 

Estimated Number 

of Days 

Section II – INDUCTION INTERVIEW – Continued 

b. 

the same number of visits as you saw during 

your last normal week in each office taking into 

account time off, holidays, and conferences? 

Note: Mark (X) response. If answer is "Yes", SKIP item 

17d for that particular office location. If answer is "No", 

then ASK item 17d for that office location. 

1 1 

No . . . 2 2 

1 

2 

1 

2 

Yes . . 

_____ 

If physician is unavailable or refuses to participate, 

enter number of visits in normal week. 

Number 

of visits 

Number of visits 

Do you have a solo practice, or are you 

associated with other physicians in a 

partnership, in a group practice, or in some 

other way (at this/that in-scope location)? Nonsolo . . . . . . . . . 

How many physicians are associated with you 

(at this/that in-scope location)? 

How many 

18a. Solo . . . . . . . . . . . . 1 1 1 1 

2 

b. 

2 2 2 

_____ _____ _____ _____ 

_____ _____ _____ _____ 

_____ _____ _____ _____ 

Office Location #1 #2 #3 #4 

_____ _____ _____ _____ 

If Solo, SKIP to item 18d. 

How many mid-level providers (i.e., nurse 

practitioners, physician assistants, and nurse 

midwives) are associated with you (at this/that 

in-scope location)? 

How many 

c. 

Approximately how many ambulatory visits do 

you expect to have at this office location? 

d. 

e. Tally of estimated number of visits 

NOTE: To obtain the total number of estimated visits 

use estimate from item 17b if "Yes" was marked in item 

17c. If "No" was marked in item 17c use the estimate 

from item 17d. 

Now, I’m going to ask about your practice at 

(in-scope location). 

FORM NAMCS-1 (11-28-2005) Page 9
 

Page 28 [ Series 13, No. 166
Series 13, No. 166 [ Page 29
 

Section II – INDUCTION INTERVIEW – Continued 

Who owns the practice (at this/that in-scope 

location)? 

Physician or 

physician group . . . 

Other hospital . . . 

Other health care corp 

Other ......... 

f. 

1 1 1 1 

2 2 2 2 

5 5 5 5 

6 6 6 6 

Office Location #1 #2 #3 #4 

Medical/ Academic 

health center . . . . 

HMO . . . . . . . . . 

4 4 4 4 

Does your practice have the ability to 

perform any of the following on site 

(at this/that in-scope location)? 

g. CT scan Yes 1

No 2

DK 3

1 

2 

3 

1 

2 

3 

1 

2 

3 

Chemotherapy Yes 1

No 2

DK 3

1 

2 

3 

1 

2 

3 

1 

2 

3 

Colonoscopy Yes 1

No 2

DK 3

1 

2 

3 

1 

2 

3 

1 

2 

3 

EKG/ECG Yes 1

No 2

DK 3

1 

2 

3 

1 

2 

3 

1 

2 

3 

Lab testing Yes 1

No 2

DK 3

1 

2 

3 

1 

2 

3 

1 

2 

3 

Mammography Yes 1

No 2

DK 3

1 

2 

3 

1 

2 

3 

1 

2 

3 

MRI Yes 1

No 2

DK 3

1 

2 

3 

1 

2 

3 

1 

2 

3 

PET scan Yes 1

No 2

DK 3

1 

2 

3 

1 

2 

3 

1 

2 

3 

Radiation 

therapy 

Yes 1

No 2

DK 3

1 

2 

3 

1 

2 

3 

1 

2 

3 

Sigmoidoscopy Yes 1

No 2

DK 3

1 

2 

3 

1 

2 

3 

1 

2 

3 

Spirometry Yes 1

No 2

DK 3

1 

2 

3 

1 

2 

3 

1 

2 

3 

Ultrasound Yes 1

No 2

DK 3

1 

2 

3 

1 

2 

3 

1 

2 

3 

Yes 1

No 2

DK 3

1 

2 

3 

1 

2 

3 

1 

2 

3 

X-Ray 

3 3 3 3 

Community Health 

Center ........ 

7 7 7 7 

Is this a single- or multi-specialty (group) 

practice (at this/that in-scope location)? 

Employee ...... 

Contractor ..... 

18d. 

Owner ........ 

2 2 2 2 

3 3 3 3 

1 1 1 

1 1 

Single ......... 2 2 

1 

2 

1 

2 

Are you a full- or part-owner, employee, or an 

independent contractor (at this/that in-scope 

location)? If "Owner" is marked then automatically 

mark "Physician or physician group" in item 18f. 

e. 1 

Multi .......... 

REFER TO FLASHCARD C. 

REFER TO FLASHCARD B. 

Page 10 FORM NAMCS-1 (11-28-2005) 
 

Page 30 [ Series 13, No. 166

FORM NAMCS-1 (11-28-2005) Page 11 

Section II – INDUCTION INTERVIEW – Continued 

Does your practice use electronic MEDICAL 

RECORDS (not including billing records)? 

22a. 1 

2 

3 

4 

Yes, all electronic 

No 

Don’t know 

Does your practice submit claims electronically 

(Electronic billing)? 

1 

2 

3 

Yes 

No 

Don’t know 

Are you a member of a practice-based 

research network (PBRN)? 

20. 1 

2 

3 

Yes 

No 

Don’t know 

21. 

SKIP to item 24 

Yes, part paper and part electronic 

b. Does your practice’s electronic medical 

record system include – 

Yes Unknown 

(1) Patient demographic information?................ 1 2 3 

(2) Computerized orders for prescriptions? .......... 

(3) Computerized orders for tests? . . . . . . . . . . . . . . . . . . 

(4) Lab results? ................................ 

(5) Imaging results? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

(6) Clinical notes? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

(7) Public health reporting?. . . . . . . . . . . . . . . . . . . . . . . . 

No 

(a) Are there warnings of drug interactions or

 contraindications provided? 

(b) Are prescriptions sent electronically 

 to the pharmacy? 

Turned off 

4 

Are orders sent electronically? 

Are out of range levels highlighted? 

Are electronic images returned? 

(a) Do they include medical history and 

 follow-up notes? 

(b) Do they include reminders for 

 guideline-based interventions 

 and/or screening tests? 

Are notifiable diseases sent electronically? 

1 2 3 4 

1 2 3 4 

1 2 3 4 

1 2 3 4 

2 3 4 

1 2 3 4 

1 2 3 4 

1 2 3 4 

1 2 3 4 

1 2 3 4 

1 2 3 4 

1 2 3 4 

1 2 3 4 

1 2 3 4 

During your last normal week of practice, about 

how many encounters of the following type did you 

make with patients: 

19. Number of encounters 

per week 

(1) Home visits (including nursing homes) 

(2) Hospital visits 

(3) Telephone consults . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

(4) Internet/e-mail consults . . . . . . . . . . . . . . . . . . . . . . . . . . 

If Yes, ask – 

If Yes, ask – 

If Yes, ask – 

If Yes, ask – 

If Yes, ask – 

If Yes, ask – 

Do you see patients in the office during the 

evening or on weekends? 

18h. 

1 

Office Location #1 #2 #3 #4 

Yes 

2 No 

3 DK 

1 Yes 

2 No 

3 DK 

1 Yes 

2 No 

3 DK 

1 Yes 

2 No 

3 DK 

1 
Section II – INDUCTION INTERVIEW – Continued 

23. Are there any of the above features of your system 1 Yes – Please specify that you do NOT use or have turned off? 

2 

3 

FR NOTE – Indicate in item 22b, last 

column, any component(s) turned off. 

No 

Unknown 

24. Are there plans for installing a new EMR system or 

replacing the current system within the next 3 

years? 

1 

2 

3 

4 

Yes 

No 

Maybe 

Unknown 

Ask items 25–28 ONCE for ALL in-scope locations. 

I would like to ask a few questions about your 

practice revenue and contracts with managed care 

plans. Percent of patient care 

25a. Roughly, what percent of your patient care revenue 

comes from – 

revenue 

(1) Medicare?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . % 

(2) Medicaid? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
 

(3) Private insurance?...........................
 

(4) Patient payments? . . . . . . . . . ..................
 

% 

% 

% 

(5) Other? – (including charity, research, CHAMPUS, VA, etc.) %

FR NOT – Categories should sum close REFER TO FLASHCARD D. to 100%. 

b. Roughly, how many managed care contracts does 

this practice have such as HMOs, PPOs, IPAs, and 

point-of-service plans? 

If necessary read:	 Managed care includes any type of
 

group health plan using financial 


incentives or specific controls to 


encourage utilization of specific 


providers associated with the plan.
 

FR NOTE –	 Include Medicare managed care and Medicaid 

managed care, but not traditional Medicare and 

Medicaid. Include any private insurance managed 

care plans. Be sure the response is about contracts and not patients. 

Include all the different plans an insurance provider may have and for which the physician has a 

contract. For example, the physician may have a 

contract for each of the plans Aetna may offer: a 

PPO, IPA, and point-of-service plan. This would 

equal 3 contracts, not 1 contract. It may be 

necessary to obtain information from the billing 

office of the practice. 

1 None – SKIP to item 26a 

2 Less than 3 

3 3 to 10 

4 More than 10 

c. Roughly, what percentage of the patient care Percent of revenue from revenue received by this practice comes from managed care (these) managed care contracts? 

Edit %
 

Page 12	 FORM NAMCS-1 (11-28-2005) 

Series 13, No. 166 [ Page 31
Page 32 [ Series 13, No. 166

Section II – INDUCTION INTERVIEW – Continued 

Are you currently accepting "new" patients into your 

practice(s)(at in-scope locations)? 

From those "new" patients, which of the following 

types of payment do you accept (at in-scope locations)? 

(1) Private insurance – 

29a. Yes 

No – SKIP to item 30 

Don’t know – SKIP to item 30 

1 

2 

3 

b. 

(2) Medicare? 

(3) Medicaid? 

(4) Workers compensation?...................... 

................................. 

................................. 

.......................... 

.............................. 

................................. 

............................... 

(5) Self-pay? 

(6) No charge? 

1 Yes 2 No 3 Don’t know

1 Yes 2 No Don’t know 

1 Yes 2 No Don’t know 

1 Yes 2 No Don’t know 

1 Yes 2 No Don’t know 

1 Yes 2 No Don’t know 

3 

3 

3 

3 

3 

(a) Capitated? 

(b) Non-capitated 

1 Yes 2 No 3 Don’t know

Which of the following factors are taken into 

account for your patient care compensation (e.g., 

base pay, bonuses, or withholds)? 

26a. 

If yes to any item in 26a, then ask item 26b. 

Otherwise, SKIP to item 27. 

(1) Your productivity (e.g., number of cases 

seen per time period)? 

. . . . . . . . . . . . . . . . . . . . . . . . . . . . 

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

. . . . . . . . . . . . . . . . . . . . . 1 Yes 2 No 3 Don’t know

(2) Patient satisfaction (e.g., results of patient

 surveys)? ................................ 1 Yes 2 No 3 Don’t know

(3) Quality of care (e.g., rates of preventive care

 services) 1 Yes 2 No 3 Don’t know

(4) Practice profiling (patterns of using certain 

services, e.g., laboratory tests, imaging, 

referrals, etc.) 1 Yes 2 No 3 Don’t know

Are performance measures on your practice 

available to the public? 

b. Yes 

No 

Don’t know 

1 

2 

3 

What percent of your patient care revenue is based 

on bonuses, returned witholds, or other 

performance-based payments? 

27. 

% 

Roughly, what percent of your patient care revenue 

comes from each of the following methods of 

payment? 

28. Percent of patient care 

revenue 

(1) Usual, customary and reasonable fee-for-service? 

(2) Discounted fee for service? .................. 

(3) Capitation?. . ................................ 

(4) Case rates (e.g., package pricing/episode 

of care)? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

% 

% 

% 

% 

FR NOTE –Categories should sum close 

to 100%. 

(5) Other? . . . ................................... % 

REFER TO FLASHCARD E. 

FORM NAMCS-1 (11-28-2005) Page 13
 
Series 13, No. 166 [ Page 33
 

Section II – INDUCTION INTERVIEW – Continued 

On a 4-point scale from a lot of difficulty, some, 

little, or no difficulty, in the last 12 months, has 

your practice experienced any difficulty in 

referring patients with the following types of 

health insurance for specialty consultations? 

30. 

(a) Medicaid 

(b) Medicare 

(c) Private insurance . . . . . . . . . ............. 

............................ 

............................. 

............................. 

(d) Uninsured 

Little 

difficulty 

Don’t 

know 

No 

difficulty 

1 2 3 4 5 

1 

1 

1 

2 3 4 5 

2 3 4 5 

2 3 4 5 

6 

6 

6 

6 

A lot of 

difficulty 

Some 

difficulty 

Not 

Applicable 

31. Do you offer any type of cervical cancer screening? Yes – Leave a NAMCS-CCS if physician’s 

specialty is GFP, IM, OB/GYN, or 

provider works at a Community 

Health Center. 

Please specify e-mail address. 

1 

2 No

3 Don’t know

1 

2 

Yes – Ask item 32 

No – SKIP to FR INSTRUCTION on page 15 

CHECK ITEM C Is provider part of the community health center sample? 

32. Provider demographics –

a. What is your year of birth? 1 9 

b. What is your sex? 1 Male

2 Female 

What is your race? 

Mark (X) one or more. 

d. 1 White

2 Black/African-American

3 Asian 

4 Native Hawaiian/Other Pacific Islander 

5 American Indian/Alaska Native 

f. What is your primary specialty?

Name of specialty Code 

g. What is your secondary specialty?

h. What is your primary board certification?

Name of specialty Code 

Board certification Code 

c. What is your ethnicity? 1 Hispanic or Latino

2 Not Hispanic or Latino

e. What is your highest medical degree? 1 MD

2 DO

3 Nurse practitioner 

4 Physician assistant 

5 Nurse midwife 

6 Other 

Ask items 32f 

SKIP to 

FR INSTRUCTION 

on page 15. 

REFER TO FLASHCARD F. 

Page 14 FORM NAMCS-1 (11-28-2005) 
Section II – INDUCTION INTERVIEW – Continued 

NOTES 

emaN noitisoP Location 

(Enter street name) 

Office 

No. 

1 

2 

3 

4 

FR NOTE – Explain to the physician and to anyone helping the physician that you would like to review 

some of the questions found on the Patient Record form. Go to page 17. 

b. 

Yes 

No – Go to page 16 

1 

2 During the period Monday, ________________ through 

Who will be helping you at each location? (Below enter the location and person’s name 

and position.) 

33a. 

Sunday, ________________ will ANYONE be available 

to help you fill out the patient record forms for this 

study (at in-scope locations) ? 

NOTE: Keep the location numbers the same as the office numbers in item 16a. 

FR NOTE – Explain to the physician that 

you would like to review some of the 

questions found on the patient record form. 

FR INSTRUCTION If physician unavailable during reporting period, SKIP to item 34b on page 18. 

32i. What is your secondary board certification?

Board certification Code 

j. What year did you graduate medical school?

Year 

k. Did you graduate from a foreign medical school? 1 Yes 

2 No

FORM NAMCS-1 (11-28-2005) Page 15
 

Page 34 [ Series 13, No. 166
Vital and Health Statistics

series descriptions

SERIES 1.	 Programs and Collection Procedures—These reports

describe the data collection programs of the National Center

for Health Statistics. They include descriptions of the methods

used to collect and process the data, definitions, and other

material necessary for understanding the data.

SERIES 2.	 Data Evaluation and Methods Research—These reports

are studies of new statistical methods and include analytical

techniques, objective evaluations of reliability of collected

data, and contributions to statistical theory. These studies also

include experimental tests of new survey methods and

comparisons of U.S. methodology with those of other

countries.

SERIES 3.	 Analytical and Epidemiological Studies—These reports

present analytical or interpretive studies based on vital and

health statistics. These reports carry the analyses further than

the expository types of reports in the other series.

SERIES 4.	 Documents and Committee Reports—These are final

reports of major committees concerned with vital and health

statistics and documents such as recommended model vital

registration laws and revised birth and death certificates.

SERIES 5.	 International Vital and Health Statistics Reports—These

reports are analytical or descriptive reports that compare U.S.

vital and health statistics with those of other countries or

present other international data of relevance to the health

statistics system of the United States.

SERIES 6.	 Cognition and Survey Measurement—These reports are

from the National Laboratory for Collaborative Research in

Cognition and Survey Measurement. They use methods of

cognitive science to design, evaluate, and test survey

instruments.

SERIES 10.	 Data From the National Health Interview Survey—These

reports contain statistics on illness; unintentional injuries;

disability; use of hospital, medical, and other health services;

and a wide range of special current health topics covering

many aspects of health behaviors, health status, and health

care utilization. They are based on data collected in a

continuing national household interview survey.

SERIES 11.	 Data From the National Health Examination Survey, the

National Health and Nutrition Examination Surveys, and

the Hispanic Health and Nutrition Examination Survey—

Data from direct examination, testing, and measurement on

representative samples of the civilian noninstitutionalized

population provide the basis for (1) medically defined total

prevalence of specific diseases or conditions in the United

States and the distributions of the population with respect to

physical, physiological, and psychological characteristics, and

(2) analyses of trends and relationships among various

measurements and between survey periods.

SERIES 12.	 Data From the Institutionalized Population Surveys—

Discontinued in 1975. Reports from these surveys are

included in Series 13.

SERIES 13.	 Data From the National Health Care Survey—These

reports contain statistics on health resources and the public’s

use of health care resources including ambulatory, hospital,

and long-term care services based on data collected directly

from health care providers and provider records.

SERIES 14.	 Data on Health Resources: Manpower and Facilities—

Discontinued in 1990. Reports on the numbers, geographic

distribution, and characteristics of health resources are now

included in Series 13.

SERIES 15.	 Data From Special Surveys—These reports contain

statistics on health and health-related topics collected in

special surveys that are not part of the continuing data

systems of the National Center for Health Statistics.

SERIES 16.	 Compilations of Advance Data From Vital and Health

Statistics—Advance Data Reports provide early release of

information from the National Center for Health Statistics’

health and demographic surveys. They are compiled in the

order in which they are published. Some of these releases

may be followed by detailed reports in Series 10–13.

SERIES 20.	 Data on Mortality—These reports contain statistics on

mortality that are not included in regular, annual, or monthly

reports. Special analyses by cause of death, age, other

demographic variables, and geographic and trend analyses

are included.

SERIES 21.	 Data on Natality, Marriage, and Divorce—These reports

contain statistics on natality, marriage, and divorce that are

not included in regular, annual, or monthly reports. Special

analyses by health and demographic variables and

geographic and trend analyses are included.

SERIES 22.	 Data From the National Mortality and Natality Surveys—

Discontinued in 1975. Reports from these sample surveys,

based on vital records, are now published in Series 20 or 21.

SERIES 23.	 Data From the National Survey of Family Growth—These

reports contain statistics on factors that affect birth rates,

including contraception, infertility, cohabitation, marriage,

divorce, and remarriage; adoption; use of medical care for

family planning and infertility; and related maternal and infant

health topics. These statistics are based on national surveys

of women of childbearing age.

SERIES 24.	 Compilations of Data on Natality, Mortality, Marriage,

Divorce, and Induced Terminations of Pregnancy—

These include advance reports of births, deaths, marriages,

and divorces based on final data from the National Vital

Statistics System that were published as supplements to the

National Vital Statistics Report (NVSR). These reports provide

highlights and summaries of detailed data subsequently

published in Vital Statistics of the United States. Other

supplements to the NVSR published here provide selected

findings based on final data from the National Vital Statistics

System and may be followed by detailed reports in Series 20

or 21.

For answers to questions about this report or for a list of reports published

in these series, contact:

Information Dissemination Staff

National Center for Health Statistics

Centers for Disease Control and Prevention

3311 Toledo Road, Room 5412

Hyattsville, MD 20782

1-866-441-NCHS (6247)
 

E-mail: nchsquery@cdc.gov
 

Internet: www.cdc.gov/nchs
 
CS117334T31005 (04/2008)DHHS Publication No. (PHS) 2008–1737, Series 13, No. 166

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