Series 10, Number 206 May 2002

Attention Deficit Disorder

and Learning Disability:

United States, 1997–98
Copyright Information

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reproduced or copied without permission; citation as to source, however, is

appreciated.

Suggested Citation

Pastor PN, Reuben CA. Attention deficit disorder and learning disability: United

States, 1997–98. National Center for Health Statistics. Vital Health Stat 10(206).

2002.

Library of Congress-Cataloging-in-Publication Data

Pastor, Patricia N.

Attention deficit disorder and learning disability, United States 1997–98 / by

Patricia N. Pastor and Cynthia A. Reuben.

p. cm.— (DHHS publication ; no. (PHS) 2002-1534) (Vital and health

statistics. Series 10, Data from the National Health interview survey ; no. 206)

Includes bibliographical references and index.

ISBN 0-8406-0579-X

1. Attention-deficit-disordered children—United States. 2. Learning disabled

children—United States. 3. Learning disabilities—United States. I. Reuben,

Cynthia A. II. National Center for Health Statistics (U.S.) III. Title. IV. Series. V.

Vital and health statistics. Series 10, Data from the National Health Survey ; no.

206.

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Series 10, Number 206

Attention Deficit Disorder

and Learning Disability:

United States, 1997–98

Data From the National

Health Interview Survey

DEPARTMENT OF HEALTH AND HUMAN SERVICES

Centers for Disease Control and Prevention

National Center for Health Statistics

Hyattsville, Maryland

May 2002

DHHS Publication No. (PHS) 2002-1534
National Center for Health Statistics

Edward J. Sondik, Ph.D., Director

Jack R. Anderson, Deputy Director

Jack R. Anderson, Acting Associate Director for

International Statistics

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

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

and Methodology

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

Analysis, Epidemiology, and Health Promotion

Edward L. Hunter, Associate Director for Planning, Budget,

and Legislation

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

Vital and Health Statistics Systems

Douglas L. Zinn, Acting Associate Director for

Management

Charles J. Rothwell, Associate Director for Information

Technology and Services

Division of Epidemiology

Thomas A. Hodgson, Ph.D., Acting Director

Thomas A. Hodgson, Ph.D., Acting Chief, Population

Epidemiology Branch
Contents

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

Highlights................................................................................................. 1

Prevalence .............................................................................................. 1

Other Health Conditions ................................................................................... 1

Use of Special Education .................................................................................. 1

Use of Health Care Services................................................................................ 2

Introduction ............................................................................................... 2

Data and Methods .......................................................................................... 2

Survey Procedures........................................................................................ 2

Measurement of Diagnosed Attention Deficit Disorder and/or Learning Disability .................................... 3

Results ................................................................................................... 3

Prevalence of Attention Deficit Disorder and/or Learning Disability ............................................... 3

Other Health Conditions ................................................................................... 3

Use of Special Education .................................................................................. 5

Use of Health Care Services................................................................................ 5

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

References ................................................................................................ 9

Appendix I

Technical Notes ......................................................................................... 11

Appendix II

Definition of Terms ...................................................................................... 11

Text Tables

A. Number of children 6–11 years of age by diagnosed Attention Deficit Disorder and/or Learning Disability, according

to selected characteristics: United States, 1997–98.......................................................... 4

B. Percent of children 6–11 years of age with Attention Deficit Disorder and/or Learning Disability by sex, according to

selected characteristics: United States, 1997–98 ............................................................ 5

C. Percent of children 6–11 years of age with selected health conditions by diagnosed Attention Deficit Disorder and/or

Learning Disability, according to sex: United States, 1997–98 ................................................ 6

D. Percent of children 6–11 years of age using selected educational and health care services by diagnosed Attention

Deficit Disorder and/or Learning Disability, according to sex: United States, 1997–98 ............................ 7

iii
Objectives

This report presents national Attention Deficit Disorder

estimates of the prevalence of

diagnosed Attention Deficit Disorder and Learning Disability: (ADD) and/or Learning Disability (LD) in

U.S. children. Differences in the

prevalence of these conditions are United States, 1997–98

examined for children with selected

sociodemographic characteristics. The Patricia N. Pastor, Ph.D., and Cynthia A. Reuben, M.A., Division of

occurrence of other health conditions

and use of educational and health care Epidemiology

services are contrasted for children with

only ADD, those with only LD, those

with both diagnoses, and those with Highlights but not with a diagnosis of only

neither diagnosis. ADD. Having private or public

health insurance was associated with

Methods Prevalence a diagnosis of only ADD.

Estimates in this report are based on

data from the National Health Interview + In 1997–98 over 2.6 million children Other Health Conditions

Survey (NHIS), a national household 6–11 years of age were reported to

survey of the civilian noninstitutionalized have ever had a diagnosis of either + The prevalence of mental retardation

population of the United States. The Attention Deficit Disorder (ADD) or and other developmental delays was

analysis focuses on 8,647 children 6–11 Learning Disability (LD). Three 1 percent for children with neither

years of age in the 1997 and 1998 percent of children 6–11 years of ADD nor LD, 31 percent for

NHIS.

age had been diagnosed with only children with only LD, and

ADD, 4 percent with only LD, and 34 percent for children with both

Results 4 percent with both conditions. ADD and LD.

In 1997–98 over 2.6 million children

6–11 years of age were reported to + The percent of boys as compared + The percent of children with health

have ever had a diagnosis of ADD or with girls with only ADD was problems including impaired vision

LD. A diagnosis of only ADD was almost 3 times greater and the and hearing, allergies, and chronic

reported for 3 percent of children, a percent with both diagnoses was health conditions other than asthma

diagnosis of only LD for 4 percent, and over 2 times greater. The percent of was greater for children with LD

a diagnosis of both conditions for 4 boys and girls with only LD was than for children with neither ADD

percent. The prevalence of ADD with or similar. nor LD.

without LD was greater for boys than

for girls. Having health insurance was + White non-Hispanic children were

associated with a diagnosis of only Use of Special Education more often diagnosed with only ADD. Living in a low-income or

mother-only family occurred more often

ADD than black non-Hispanic or + The percent of children enrolled in

Hispanic children. The percent of special education was nearly 5 times among children with a diagnosis of LD. children with only LD did not vary Children with LD were nearly five greater for children with LD than

significantly by race or ethnicity. times more likely to be in special for children with only ADD and

education than children with a + The association between other over 23 times greater than for

diagnosis of only ADD. Children with sociodemographic characteristics and children with neither diagnosis.

ADD, in contrast to children without this diagnoses of ADD and LD varied by Among children with LD, the

diagnosis, more often had contact with diagnostic category. Living in a low- percent of boys and girls in special

a mental health professional, used

prescription medication regularly, and income or mother-only family was education was similar.

had frequent health care visits. associated with a diagnosis of LD,

Keywords: children’s health c

learning and behavioral disorders c NOTE: This report was prepared in the Population Epidemiology Branch of the Division of Epidemiology.

health care utilization The assistance and expertise of the following persons who contributed to this report is gratefully

acknowledged. Diane M. Makuc, Thomas A. Hodgson, and Elsie R. Pamuk of the Office of Analysis,

Epidemiology, and Health Promotion; and Gloria A. Simpson of the Division of Health Interview Statistics

in the Office of Vital and Health Statistics Systems, and Ann M. Hardy of the National Institutes of Health

provided helpful comments on the paper. The report was edited by Thelma W. Sanders and typeset by

Annette F. Holman of the Publications Branch, Division of Data Services.

Page 1
Page 2 [ Series 10, No. 206

Use of Health Care

Services

+ Use of mental health services during

the past 12 months was greater

among children with a diagnosis of

ADD or LD: 17 percent for those

with only LD, 34 percent for those

with only ADD, and 51 percent for

those with both diagnoses. Among

children with neither diagnosis,

3 percent had contact with a mental

health professional during the past

12 months.

+ Contact with a medical specialist

other than a mental health

professional was greater for children

with either ADD or LD than for

children with neither diagnosis.

+ Regular use of prescription

medication was highest among

children with ADD: 54 percent for

children with only ADD and

61 percent for children with both

ADD and LD. Use of prescription

medication was lower among

children without ADD: 14 percent

for children with only LD and 6

percent for children with neither

ADD nor LD.

+ The percent of children with four or

more health care visits during the

past 12 months was 34 percent for

children with only LD, 45 percent

for children with only ADD, and

51 percent for children with both

diagnoses. Among children with a

diagnosis of neither ADD nor LD,

23 percent had four or more health

care visits during the past 12

months.

Introduction

I

n the last 30 years, the diagnosis

and treatment of behavioral and

learning disorders have become

major health concerns for school-aged

children in the United States. An

increasing number of adults have

identified underachievement and failure

in school as serious problems facing

youth (1). At the same time, educators

have reported a rise in the number of

school-aged children with disabling

behavioral and learning disorders (2).

Finally, pediatricians have noted an

increasing number of outpatient visits

related to psychosocial conditions in

children. Results from a national survey

of pediatricians in 1996, for example,

reported that 19 percent of all pediatric

visits involved a child or an adolescent

with a psychosocial problem requiring

attention or intervention. As the authors

of this study note: ‘‘. . . psychosocial

problems are the most common chronic

condition for pediatric visits, eclipsing

asthma and heart disease’’ (3).

The increased prevalence of

behavioral and learning problems in

school-aged children has been linked to

changes occurring in families, schools,

and medical practice. In families,

marital instability, inadequate day care,

and poverty have adversely affected

children’s lives and contributed to the

rise of behavioral and learning problems

(4,5). In schools, legislative and judicial

mandates have expanded special

education services (6,7). In medical

practice, widespread acceptance of drug

therapy for behavioral disorders has

facilitated diagnosis and treatment of

these conditions in ambulatory care

settings (8,9). Lack of health care

insurance and limited access to mental

health services, though, have very likely

left conditions in some children

undiagnosed and untreated (10).

The present study examines two

disorders linked to behavioral and

learning problems in school-aged

children, ADD and LD. Although ADD

and LD are among the most widely

researched conditions of childhood,

limited information is available on the

national prevalence of these disorders

and on the sociodemographic

characteristics of U.S. children having

these disorders. The present study

explores the epidemiology of ADD and

LD with data from a large, nationally

representative health survey. The

epidemiology of ADD and LD is

investigated first, by estimating the

prevalence of diagnosed ADD and LD,

and secondly, by describing the

sociodemographic characteristics, other

health conditions, and use of educational

and health care services by children

with and without diagnosed ADD and

LD. In contrast to previous studies that

have examined the characteristics of

children with ADD and LD separately,

the present report takes into account the

frequent joint occurrence of ADD and

LD and presents data for children in the

following diagnostic categories: children

with neither a diagnosis of ADD nor LD

(NEITHER), those with a diagnosis of

ADD, but not LD (ADD/noLD), those

with a diagnosis of LD, but not ADD

(LD/noADD), and those with a

diagnosis of both ADD and LD

(BOTH). Throughout the report, results

are shown for all children 6–11 years of

age and for boys and girls separately.

Data and Methods

Survey Procedures

The data source for the results

reported here is the 1997 and

1998 National Health Interview

Survey (NHIS). The NHIS is a

nationally representative household

survey conducted by the National Center

for Health Statistics (NCHS) that

collects information on health status, use

of health care, and sociodemographic

characteristics of the civilian

noninstitutionalized population. The

design of the NHIS sample permits the

merging of data from 1997 and 1998

into a single sample (11). During these

two survey years, 78,041 households

participated in the NHIS resulting in a

response rate of 92 percent in 1997 and

90 percent in 1998.

In each family with children under

18 years of age, one child was randomly

selected. Additional information for this

child was obtained by interviewing an

adult family member who was

knowledgeable about the child’s health

(12). The present report focuses on data

for the 8,647 children 6–11 years of age

in the child sample. The response rate

for the sample child section of the NHIS

was 84 percent in 1997 and 82 percent

in 1998. In over 90 percent of the

families, a parent was the respondent

providing information about the sample

child. Data were collected on

sociodemographic characteristics,
Series 10, No. 206 [ Page 3

including a child’s age at interview, sex,

race, ethnicity, birthweight, family

structure, family income, residence in a

metropolitan statistical area (MSA), and

health insurance coverage. Information

on health conditions included diagnoses

of ADD, LD, mental retardation and

other developmental delays, vision and

hearing problems, allergies, asthma, and

other chronic health conditions. Use of

educational services was measured by

asking if a child was currently receiving

special education or early intervention

services. Because only school-aged

children are included in the present

analysis, the services received refer to

special education programs. Use of

health care services during the past 12

months was assessed by asking if a

child had contact with various types of

health care providers and how often a

child was seen by a health care provider.

Use of medication was determined by

asking if a child had a condition for

which he or she had regularly taken

prescription medication for at least 3

months. (See Appendix I, Technical

Notes for more information about the

NHIS sample and survey questionnaire.)

Percents and standard errors were

calculated using SUDAAN, a statistical

program for survey data analysis that

adjusts for the effects of complex

sampling designs (13). Differences

between percents were evaluated for

statistical significance at the 0.05 level

with two-sided tests. (See Appendix I,

Technical Notes for details.) The

estimated number of children with

diagnoses of ADD and/or LD

(NEITHER, ADD/noLD, LD/noADD,

and BOTH) are shown by selected

sociodemographic characteristics in

table A.

Measurement of Diagnosed

Attention Deficit Disorder

and Learning Disability

A history of diagnosed ADD and

LD was determined by responses to the

following questions:

+ Has a doctor or health professional

ever told you that (sample child)

had Attention Deficit Disorder?

+ Has a representative from a school

or a health professional ever told

you that (sample child) had a

learning disability?

The term, ‘‘Attention Deficit Disorder’’

refers to clinical diagnoses of ADD and

ADHD (Attention Deficit Hyperactivity

Disorder), including all subtypes for

ADD and ADHD. The term, ‘‘Learning

Disability’’ refers to different types of

specific learning disabilities, namely

disabilities in listening, speaking, basic

reading skills, reading comprehension,

written expression, mathematical

calculation, and mathematical reasoning.

The item nonresponse rate for the

questions on ADD and LD was

0.5 percent. Forty-six children who had

missing information on ADD or LD

were excluded from the analysis.

The age at which children were

diagnosed with ADD or LD was not

obtained. Most children, however, are

diagnosed with ADD or LD in

elementary school (14). The present

study focuses on children 6–11 years of

age in an effort to examine the

characteristics of children with recent

diagnoses of ADD and LD. Diagnoses

reported by parents were not verified by

comparing survey responses with

information from children’s medical or

school records. Finally, undiagnosed

cases of ADD and LD were not

included in the present analysis because

the survey questions asked parents to

report only diagnosed cases of ADD and

LD.

Results

Prevalence of Attention

Deficit Disorder and/or

Learning Disability

A mong children 6–11 years of

age, nearly 7 percent were

reported to have a diagnosis of

ADD and approximately 8 percent a

diagnosis of LD. Specifically, 3 percent

of children 6–11 years of age had ever

been diagnosed with ADD/noLD,

4 percent with LD/noADD, and

4 percent with BOTH (table B). The

prevalence of ever having a diagnosis of

ADD/noLD, LD/noADD, or BOTH was

higher among children 9–11 years of

age than among those 6–8 years of age.

The prevalence of ADD was also greater

in boys than in girls, almost three times

greater for a diagnosis of ADD/noLD

and over two times greater for a

diagnosis of both ADD and LD. In

contrast, the prevalence of LD/noADD

was not significantly different for boys

and girls. The effect of race and

ethnicity varied by diagnostic category.

White non-Hispanic children were more

often diagnosed with ADD/noLD than

black non-Hispanic or Hispanic children.

Racial and ethnic differences in the

percent of all children with LD

(LD/noADD and BOTH) were not

statistically significant.

The effect of other sociodemographic characteristics varied among the

diagnostic categories. Low birthweight

was related to having a diagnosis of

LD/noADD but not ADD (ADD/noLD

and BOTH). Living in a mother-only or

low-income family was linked to having

LD (LD/noADD or BOTH) but not to

ADD/noLD. Having either private or

public health insurance was associated

with a diagnosis of ADD/noLD. The

percent of children with LD

(LD/noADD and BOTH) was greater

among children with Medicaid than

among those with private insurance or

no insurance. Neither ADD nor LD was

related to living in a metropolitan area.

Among boys, the variables

associated with a diagnosis of ADD and

LD were generally similar to the

predictors for all children. Among girls,

the overall pattern of results was also

similar to that of all children, but fewer

variables were significantly associated

with the diagnoses of ADD and LD.

Other Health Conditions

Children in the diagnostic categories

of ADD/noLD, LD/noADD, and BOTH

differed in regard to the prevalence of

other health conditions as compared

with children with neither a diagnosis of

ADD nor LD. Table C shows the

prevalence of five health conditions:

mental retardation and other

developmental delays, problems with

vision and hearing, allergies, asthma,

and other chronic health conditions.
Page 4 [ Series 10, No. 206

Table A. Number of children 6–11 years of age by diagnosed Attention Deficit Disorder and/or Learning Disability, according to selected

characteristics: United States, 1997–98

All All

Characteristic children1 NEITHER2 ADD/noLD3 LD/noADD4 BOTH5 children1 NEITHER2 ADD/noLD3 LD/noADD4 BOTH5

Average annual population estimates (Number in 1,000s) Sample size

Total .................... 24,160 21,527 784 1,010 839 8,601 7,697 270 345 289

Sex

Boys .................... 12,311 10,556 582 576 597 4,413 3,806 202 197 208

Girls .................... 11,850 10,970 203 434 242 4,188 3,891 68 148 81

Age

6–8 years ................. 12,195 11,171 281 409 333 4,358 3,993 106 146 113

9–11 years ................ 11,966 10,355 503 601 506 4,243 3,704 164 199 176

Race/ethnicity6

White non-Hispanic ........... 15,789 13,944 649 621 575 4,629 4,084 193 180 172

Black non-Hispanic ........... 3,735 3,312 69 201 153 1,415 1,264 34 62 55

Hispanic .................. 3,573 3,268 48 165 93 2,237 2,049 35 95 58

Birthweight

Low (less than 2,500 grams) ..... 1,529 1,254 65 134 75 608 509 21 45 33

Not low (2,500 grams or more) .... 21,171 18,975 680 819 697 7,452 6,697 233 285 237

Family structure7

Mother and father ............ 17,497 15,848 525 609 514 5,808 5,282 168 198 160

Mother only................ 5,308 4,538 203 325 242 2,200 1,901 80 117 102

Family income

$20,000 or more ............. 18,133 16,334 606 661 532 6,128 5,535 202 222 169

Less than $20,000 ........... 5,021 4,288 143 302 287 2,069 1,791 59 105 114

Residence in MSA8

Central city, MSA ............ 6,553 5,862 190 294 208 2,694 2,427 78 104 85

Not central city, MSA .......... 12,676 11,324 442 493 418 4,334 3,880 139 173 142

Not MSA ................. 4,931 4,341 153 223 214 1,573 1,390 53 68 62

Health insurance coverage

Uninsured ................. 3,121 2,847 58 142 75 1,283 1,177 27 50 29

Medicaid9 ................. 3,738 2,982 158 304 295 1,434 1,159 54 107 114

Private10 ................. 17,165 15,576 566 562 461 5,823 5,307 187 186 143

ADD is Attention Deficit Disorder.

LD is Learning Disability.

1Data do not include children with unknown responses to the questions on ADD and LD.

2NEITHER includes children who have never had a diagonsis of either ADD or LD.

3ADD/noLD includes children who have ever had a diagnosis of ADD and have never had a diagnosis of LD.

4LD/noADD includes children who have ever had a diagnosis of LD and have never had a diagnosis of ADD.

5BOTH includes children who have ever had a diagnosis of both ADD and LD.

6Data are not shown for non-Hispanic children of other races due to small sample size.

7Mother and father refer to biological, adoptive, step, and foster parents. Data are not shown for children in other family types due to small sample size.

8MSA is metropolitan statistical area.

9Medicaid includes children insured only by Medicaid.

10Private includes children covered by private insurance, those with non-Medicaid public insurance, and those with both private and public insurance.

Among children with neither ADD nor the percent with mental retardation or Health problems, including impaired

LD, the percent reported to be mentally other developmental delays was vision and hearing, allergies, and

retarded or to have other developmental substantially greater, 31 percent for chronic health conditions other than

delays was 1 percent. Among children those with LD/noADD and 34 percent asthma, were reported more frequently

with ADD/noLD, the percent with for those with BOTH. Further, the for children with LD (LD/noADD and

mental retardation or other develop- percent of the children with LD reported BOTH) than for children with neither

mental delays could not be precisely to be mentally retarded was 8 percent ADD nor LD. For example, among

estimated, but the number of children for those with LD/noADD and children with LD/noADD, the percent

with these disorders was small (n = 18). 10 percent for those with both ADD and reported to have other chronic health

By contrast, among children with LD, LD (data not shown in table C). conditions was over twice that of

children with neither ADD nor LD.
Series 10, No. 206 [ Page 5

Table B. Percent of children 6–11 years of age with Attention Deficit Disorder and/or Learning Disability by sex, according to selected

characteristics: United States, 1997–98

All children Boys Girls

Characteristic ADD/noLD1 LD/noADD2 BOTH3 ADD/noLD1 LD/noADD2 BOTH3 ADD/noLD1 LD/noADD2 BOTH3

Percent (standard error)

Total ....................... 3.3 (0.23) 4.2 (0.27) 3.5 (0.23) 4.7 (0.37) 4.7 (0.39) 4.9 (0.39) 1.7 (0.26) 3.7 (0.37) 2.0 (0.28)

Age

6–8 years .................... 2.3 (0.27) 3.4 (0.31) 2.7 (0.30) 3.3 (0.47) 3.8 (0.45) 4.0 (0.50) 1.3 (0.28) 2.9 (0.43) 1.5 (0.34)

9–11 years ................... 4.2 (0.40) 5.0 (0.43) 4.2 (0.37) 6.1 (0.64) 5.6 (0.60) 5.7 (0.60) 2.2 (0.44) 4.4 (0.61) 2.6 (0.43)

Race/ethnicity4

White non-Hispanic .............. 4.1 (0.33) 3.9 (0.33) 3.6 (0.30) 6.0 (0.53) 4.2 (0.45) 5.0 (0.50) 2.1 (0.37) 3.7 (0.46) 2.2 (0.38)

Black non-Hispanic .............. 1.8 (0.34) 5.4 (0.84) 4.1 (0.67) 2.7 (0.62) 7.6 (1.40) 6.5 (1.14) * 3.2 (0.83) *

Hispanic ..................... 1.4 (0.29) 4.6 (0.71) 2.6 (0.40) 1.8 (0.39) 4.8 (0.75) 3.1 (0.61) * 4.5 (1.22) 2.0 (0.50)

Birthweight

Low (Less than 2,500 grams) ........ 4.3 (1.04) 8.8 (1.37) 4.9 (1.06) 6.9 (1.95) 8.7 (1.90) 6.5 (1.56) * 8.8 (1.99) *

Not low (2,500 grams or more) ....... 3.2 (0.25) 3.9 (0.29) 3.3 (0.24) 4.7 (0.40) 4.6 (0.42) 4.6 (0.42) 1.7 (0.28) 3.1 (0.36) 2.0 (0.29)

Family structure5

Mother and father ............... 3.0 (0.27) 3.5 (0.28) 2.9 (0.26) 4.4 (0.45) 4.0 (0.41) 3.8 (0.42) 1.5 (0.27) 3.0 (0.36) 2.0 (0.34)

Mother only................... 3.8 (0.55) 6.1 (0.76) 4.6 (0.55) 5.4 (0.85) 6.6 (0.94) 7.0 (0.95) * 5.7 (1.15) 2.0 (0.52)

Family income

$20,000 or more ................ 3.3 (0.27) 3.7 (0.27) 2.9 (0.26) 4.8 (0.45) 3.9 (0.38) 4.2 (0.43) 1.9 (0.31) 3.4 (0.39) 1.7 (0.29)

Less than $20,000 .............. 2.8 (0.46) 6.0 (0.82) 5.7 (0.63) 4.3 (0.78) 7.4 (1.11) 7.3 (0.97) * 4.5 (1.10) 3.9 (0.82)

Health insurance coverage

Uninsured .................... 1.9 (0.39) 4.6 (0.91) 2.4 (0.50) 2.9 (0.72) 5.1 (1.08) 3.6 (0.81) * * *

Medicaid6 .................... 4.2 (0.72) 8.1 (0.99) 7.9 (0.88) 6.1 (1.22) 9.2 (1.40) 11.0 (1.42) * 6.9 (1.31) 4.4 (1.04)

Private7 ..................... 3.3 (0.28) 3.3 (0.27) 2.7 (0.26) 4.8 (0.46) 3.6 (0.39) 3.6 (0.42) 1.8 (0.31) 2.9 (0.36) 1.7 (0.30)

Residence in MSA8

Central city, MSA ............... 2.9 (0.39) 4.5 (0.56) 3.2 (0.40) 4.1 (0.68) 5.0 (0.75) 4.7 (0.70) 1.7 (0.41) 4.0 (0.86) 1.6 (0.42)

Not central city, MSA ............. 3.5 (0.36) 3.9 (0.33) 3.3 (0.33) 5.1 (0.59) 4.5 (0.49) 4.5 (0.53) 1.9 (0.40) 3.3 (0.44) 2.1 (0.40)

Not MSA .................... 3.1 (0.44) 4.5 (0.71) 4.3 (0.59) 4.7 (0.75) 4.8 (0.99) 5.9 (0.94) * 4.2 (0.89) 2.5 (0.70)

ADD is Attention Deficit Disorder.

LD is Learning Disability.

* Figure does not meet standard of reliability or precision.

1ADD/noLD includes children who have ever had a diagnosis of ADD and have never had a diagnosis of LD.

2LD/noADD includes children who have ever had a diagnosis of LD and have never had a diagnosis of ADD.

3BOTH includes children who have ever had a diagnosis of both ADD and LD.

4Data are not shown for non-Hispanic children of other races due to small sample size.

5Mother and father refer to biological, adoptive, step, and foster parents. Data are not shown for children in other family types due to small sample size.

6Medicaid includes children insured only by Medicaid.

7Private includes children covered by private insurance, those with non-Medicaid public insurance, and those with both private and public insurance.

8MSA is metropolitan statistical area.

Among children with both ADD and

LD, the percent with other chronic

conditions was three times that of

children with neither diagnosis.

However, the percent with other chronic

health conditions did not differ

significantly between children with

ADD/noLD and those with neither ADD

nor LD.

Use of Special Education

The use of special education

differed substantially between children

without LD (NEITHER and

ADD/noLD) as compared with children

with LD (LD/noADD and BOTH)

(table D). Among children with the

diagnosis of LD, overall 54 percent were

in special education. This was nearly 5

times greater than the percent observed

for children with ADD/noLD and over

23 times the percent reported for

children with neither ADD nor LD.

Among children with LD/noADD,

46 percent attended special education,

and among those with both ADD and

LD, 65 percent were in special

education. Among children with LD, the

percent of boys and girls in special

education was similar.

Use of Health Care

Services

Whether a child had contact with a

mental health professional during the

past 12 months also differed markedly

among children in the various diagnostic

categories (table D). Among children

with neither ADD nor LD, only

3 percent had contact with a mental

health professional during the past 12

months. Among children diagnosed with

ADD or LD, the percent having contact

with a mental health professional was

17 percent for those with LD/noADD,
Page 6 [ Series 10, No. 206

Table C. Percent of children 6–11 years of age with selected health conditions by diagnosed Attention Deficit Disorder and/or Learning

Disability, according to sex: United States, 1997–98

Health conditions NEITHER1 ADD/noLD2 LD/noADD3 BOTH4

All children Percent (standard error)5

Mental retardation/ODD6 .................. 1.3 (0.16) * 30.7 (2.97) 34.4 (3.38)

Hearing or vision problems7 ................ 3.0 (0.23) * 12.2 (2.22) 9.5 (2.07)

Allergies8 ........................... 27.3 (0.61) 31.7 (3.63) 35.6 (3.05) 39.3 (3.27)

Asthma9 ............................ 12.1 (0.44) 17.4 (2.64) 16.5 (2.46) 16.6 (2.63)

Other chronic health condition10 ............. 4.1 (0.26) 4.6 (1.23) 9.7 (1.77) 12.5 (2.42)

Boys

Mental retardation/ODD6 .................. 2.0 (0.30) * 30.4 (3.76) 34.5 (3.98)

Hearing or vision problems7 ................ 2.8 (0.32) * 10.6 (2.46) 7.6 (2.24)

Allergies8 ........................... 28.4 (0.89) 31.6 (4.33) 36.8 (3.76) 39.0 (3.64)

Asthma9 ............................ 15.0 (0.73) 18.7 (3.06) 17.9 (3.03) 19.7 (3.32)

Other chronic health condition10 ............. 4.1 (0.36) * 8.8 (2.04) 10.8 (2.46)

Girls

Mental retardation/ODD6 .................. 0.6 (0.14) * 31.2 (4.80) 34.2 (6.64)

Hearing or vision problems7 ................ 3.2 (0.33) * 14.3 (3.85) *

Allergies8 ........................... 26.1 (0.85) 31.9 (6.63) 34.0 (4.93) 39.8 (6.84)

Asthma9 ............................ 9.2 (0.55) * 14.6 (4.02) *

Other chronic health condition10 ............. 4.2 (0.36) * 11.0 (3.11) *

ADD is Attention Deficit Disorder.

LS is Learning Disability.

* Figure does not meet standard of reliability or precision.

1NEITHER includes children who have never had a diagnosis of either ADD or LD.

2ADD/noLD includes children who have ever had a diagnosis of ADD and have never had a diagnosis of LD.

3LD/noADD includes children who have ever had a diagnosis of LD and have never had a diagnosis of ADD.

4BOTH includes children who have ever had a diagnosis of both ADD and LD.

5Unknowns for the variables of interest are not included in denominators used for the calculation of percents and standard errors.

6Parental report of diagnosed mental retardation or other developmental delay, autism, or Down syndrome.

7Parental report of blindness, deafness, or serious difficulty seeing or hearing.

8Parental report of a digestive allergy, skin allergy, hay fever, respiratory allergy, or frequent ear infections (three or more) during the past 12 months.

9Parental report of ever having a diagnosis of asthma.

10Parental report of diagnosed Cerebral Palsy, Muscular Dystrophy, Cystic Fibrosis, Sickle Cell Anemia, Diabetes, Arthritis, or heart disease; also a parental report of frequent diarrhea or colitis,

anemia, or seizures during the past 12 months.

34 percent for those with ADD/noLD,

and 51 percent for those with both ADD

and LD. The percent of boys and girls

having contact with a mental health

professional did not differ.

The use of prescription medication

also varied by diagnostic category.

Among children with neither a diagnosis

of ADD nor LD, only 6 percent used

prescription medication on a regular

basis. Among children with a diagnosis

of LD/noADD, medication use was

greater, but still modest at 14 percent. In

contrast, medication use was

substantially greater among children

with a diagnosis of ADD, 54 percent for

children with ADD/noLD and 61 percent

for children with both ADD and LD.

Use of prescription medication was

similar among boys and girls with

ADD/noLD, but greater for boys than

for girls among children with both ADD

and LD.

The percent of children having

contact with a medical specialist other

than a mental health professional was

greater for children with either a

diagnosis of ADD or LD than for those

with neither diagnosis. The percent

having contact with a therapist, such as

a physical or occupational therapist, was

greater for children with LD

(LD/noADD and BOTH) than for

children with neither ADD nor LD.

Finally, approximately one-half of the

children with ADD (ADD/noLD and

BOTH) had four or more health care

visits during the past 12 months as

compared with less than a quarter of

children with neither diagnosis. Slightly

over a third of children with LD/noADD

had frequent health care visits. In each

diagnostic category, the percent of boys

and girls with frequent health care visits

was similar.

Discussion

This report presents findings from

the first national health survey to

collect data on two major

behavioral and learning disorders,

diagnosed ADD and LD. These results

show that ADD and LD are among the

most common chronic conditions

affecting school-aged children in the

United States. Over 2.6 million children

6–11 years of age were reported to have

either a diagnosis of ADD or LD. The

consequences of ADD and LD for

children, their families, and society are

considerable (10,15,16). For children,

these conditions interfere with academic

achievement and social development.

For families, these conditions require

diagnostic and treatment services that

are often not covered by health
Series 10, No. 206 [ Page 7

Table D. Percent of children 6–11 years of age using selected educational and health care services by diagnosed Attention Deficit Disorder

and/or Learning Disability according to sex: United States, 1997–98

Educational and healh care services NEITHER1 ADD/noLD2 LD/noADD3 BOTH4

All children Percent (standard error)5

Enrolled in special education6 .............. 2.3 (0.20) 11.7 (2.20) 45.9 (3.24) 64.7 (3.18)

Contacted a mental health professional7 ........ 3.4 (0.26) 33.9 (3.43) 16.5 (2.50) 51.1 (3.72)

Used prescription medication8 .............. 5.8 (0.30) 53.6 (3.55) 13.8 (2.12) 61.4 (3.47)

Contacted a medical specialist9 ............. 9.4 (0.41) 20.3 (3.24) 17.0 (2.37) 28.4 (3.17)

Contacted a therapist10 .................. 3.9 (0.27) * 26.2 (3.02) 24.8 (2.97)

Had four or more health care visits11 .......... 22.6 (0.60) 44.8 (3.56) 34.3 (3.13) 50.6 (3.77)

Boys

Enrolled in special education6 .............. 2.9 (0.33) 11.8 (2.49) 48.5 (4.12) 63.3 (3.83)

Contacted a mental health professional7 ........ 3.9 (0.41) 35.2 (3.92) 17.9 (3.20) 53.3 (4.23)

Used prescription medication8 .............. 6.7 (0.46) 55.7 (4.20) 16.1 (2.87) 68.2 (4.10)

Contacted a medical specialist9 ............. 9.5 (0.57) 21.3 (3.88) 17.5 (3.25) 28.9 (3.81)

Contacted a therapist10 .................. 4.2 (0.39) * 27.2 (3.67) 25.7 (3.46)

Had four or more health care visits11 .......... 22.4 (0.84) 44.5 (4.01) 34.9 (4.00) 52.8 (4.27)

Girls

Enrolled in special education6 .............. 1.7 (0.23) * 42.5 (5.10) 68.0 (6.45)

Contacted a mental health professional7 ........ 2.9 (0.33) 30.0 (6.79) 14.7 (3.93) 45.7 (6.63)

Used prescription medication8 .............. 5.0 (0.39) 47.7 (6.99) 10.7 (3.11) 44.7 (6.77)

Contacted a medical specialist9 ............. 9.2 (0.55) * 16.3 (3.76) 27.3 (6.24)

Contacted a therapist10 .................. 3.5 (0.38) * 24.8 (4.81) 22.8 (5.47)

Had four or more health care visits11 .......... 22.8 (0.81) 45.9 (7.39) 33.5 (4.75) 45.3 (6.83)

ADD is Attention Deficit Disorder.

LD is Learning Disability.

* Figure does not meet standard of reliability or precision.

1NEITHER includes children who have never had a diagnosis of either ADD or LD.

2ADD/noLD includes children who have ever had a diagnosis of ADD and have never had a diagnosis of LD.

3LD/noADD includes children who have ever had a diagnosis of LD and have never had a diagnosis of ADD.

4BOTH includes children who have ever had a diagnosis of both ADD and LD.

5Unknowns for the variables of interest are not included in denominators used for the calculation of percents and standard errors.

6Receives special education services.

7Saw or spoke to a mental health professional such as a psychiatrist, psychologist, psychiatric nurse, or clinical social worker during the past 12 months.

8Has a condition for which prescription medication had been taken regularly for at least 3 months.

9Saw or spoke to a medical specialist (other than a gynecologist, psychiatrist, or ophthamalogist) during the past 12 months.

10Saw or spoke to a physical therapist, speech therapist, respiratory therapist, audiologist, or occupational therapist.

11Four or more visits to a doctor or other health professional during the past 12 months; overnight hospitalizations, emergency room visits, home visits, or telephone calls are not included.

insurance. Finally, for society,

behavioral and learning disorders create

substantial demands on institutions and

individuals providing health care and

educational services for children.

The NHIS is the first national

survey to include questions on the

prevalence of both diagnosed ADD and

LD in school-aged children. Differences

in the way in which ADD and LD were

measured in other national and

community-based studies make it

difficult to compare these estimates with

the results from the NHIS. Nonetheless,

a comparison of the prevalence of ADD

estimated from recent community-based

studies with results from the present

study places the 1997–98 NHIS estimate

of 7 percent for ADD within the range

of values reported in prior studies

(4.5–12 percent) (14). A comparison of

the prevalence of LD from the 1988

Child Health Survey (NHIS-CH) with

the estimate from the present study

shows a modest increase for children

6–11 years of age, from 7 percent to

8 percent (5). Data collected by the U.S.

Department of Education also indicate a

small increase in the percent of students

less than 21 years of age with LD in

special education, from 4.9 percent in

1988–89 to 5.9 percent in 1997–98 (18).

Finally, the 1997 Survey of Income and

Program Participation, which asked

about a current learning disability, such

as dyslexia, reported that 5 percent of

children 6–14 years of age had LD (19).

In the medical and psychological

literature, there are few studies assessing

the accuracy with which parents report

diagnosed behavioral and learning

disorders. A comparison of maternal

reports about children’s physical health

with information in medical records,

though, has generally shown a high

level of agreement between these

sources for serious health conditions

entailing ongoing care such as asthma

(20). An evaluation of diagnostic

reporting in the NHIS, which compared

survey responses with data from medical

records, also demonstrated greater

agreement for conditions requiring a

physician’s diagnosis and care (21). In

the case of health events such as

injuries, survey data obtained from

parents appear to be more complete than

findings from medical records (20).

Similarly, reports from a parent about

diagnosed ADD and LD may also be

preferable to information from either a

child’s medical or school record. A

parent may be the one informant who
Page 8 [ Series 10, No. 206

can describe findings from evaluations

by health care providers and school

personnel and also provide detailed

information about a child’s

sociodemographic characteristics.

Although there is no way to assess the

completeness of parental reports in the

NHIS, the present study has attempted

to minimize the effect of lapses in a

parent’s memory by limiting the

analysis to young school-aged children.

Parents’ understanding of the

diagnostic terms used in the NHIS is

another factor that may have affected

responses to the questions about ADD

and LD. In 1997 and 1998, the NHIS

asked parents about a diagnosis of

‘‘Attention Deficit Disorder.’’ Some

parents who were told by a health

professional that their child had ADHD

or one of the specific diagnoses in the

revised third edition of the Diagnostic

Statistical Manual of Mental Disorders

(DSM-III-R) or in the fourth edition

(DSM-IV) may not have answered

‘‘yes’’ to a survey question asking about

‘‘Attention Deficit Disorder’’ (22,23).

Although the relatively high prevalence

rate of ADD in the present study

suggests that underreporting of this

diagnosis by parents was minimal, a rate

based on only diagnosed cases of ADD

may not represent the true extent of this

disorder in children.

Parental understanding of diagnostic

terms could also have influenced the

findings about LD. To educators and

clinicians, ‘‘Learning Disability’’ is a

term that identifies children whose

academic achievement is significantly

below the level predicted by their

measured intelligence or ability to learn.

For example, the Individuals with

Disabilities Education Act (IDEA), the

major Federal legislation regulating

special education services in public

schools, defines a specific learning

disability as a disorder in one or more

basic psychological processes involved

in understanding or in using language,

spoken or written, that may manifest

itself in an imperfect ability to listen,

speak, read, write, spell, or to do

mathematical calculations (24). IDEA

further stipulates that the gap between a

child’s achievement and ability is one

that is not primarily attributable to the

result of visual, hearing, or motor

disabilities, of mental retardation, of

emotional disturbance, or of

environmental, cultural, or economic

disadvantage (24). To parents, though,

LD may have a more general meaning

and may be used to identify a broader

group of underachieving children,

including those with academic problems

due to mental retardation, sensory

deficits, serious psychological disorders,

or socioeconomic deprivation.

Two findings from the present study

suggest that some parents reported a

diagnosis of LD for learning problems,

which are not covered by the precise

definition of this disorder. First, over

one-half of the children in the 1997–98

NHIS who had a diagnosis of ADD

were also reported to have a diagnosis

of LD. Past studies of the joint

occurrence of ADD and LD have

demonstrated a greater risk of LD

among children diagnosed with ADD.

Estimates of the occurrence of LD

among children with ADD, though, have

ranged from 10–20 percent when

stringent clinical criteria are used for the

diagnosis of LD (25). The high

proportion of children with both

diagnoses in the present study raises the

possibility that parents may have

interpreted the term ‘‘Learning

Disability’’ to include a broad range of

academic problems including some that

do not fit the criteria for LD. Secondly,

the relatively high proportion of

mentally retarded children who were

described to have LD in the 1997–98

NHIS also suggests that parents may

have interpreted the term ‘‘Learning

Disability’’ broadly. However, it is

possible that parental reports of

diagnosed ADD, LD, and mental

retardation for a particular child

accurately reflect the different diagnoses

provided by various health care and

educational professionals.

In addition to problems with

parental reporting of diagnoses,

estimates of ADD and LD from the

1997–98 NHIS may have been affected

by shifts in the diagnostic criteria used

to identify these conditions. In the case

of ADD, the present study includes

parents’ reports of diagnoses based on

the criteria of the DSM-III-R and

DSM-IV (22,23). Moreover, some

pediatricians and primary care

physicians may not have used the

criteria in either edition of DSM to

diagnose ADD (26). Finally, health

insurance coverage, access to mental

health services, and attitudes of parents

and providers are additional factors that

may have influenced the extent to which

children exhibiting similar behavioral

problems were diagnosed as having

ADD (10,27).

There is also some indication that

the criteria used to identify LD may

have shifted over time. Since the

mid-1970s, an increasing number of

students in special education programs

have been identified as having LD. In

1976–77, children with specific learning

disabilities constituted 1.8 percent of the

children enrolled in public schools. By

1997–98, the percent had more than

tripled and was 5.9 percent (18). The

trend in LD is striking when contrasted

with the nearly stable percent of

children during the same period

classified as having speech or language,

hearing, orthopedic, or visual

impairments. Changes in Federal, State,

and local policies affecting diagnosis of

LD, as well as increases in funding for

special education services, are factors

that may have influenced the

identification of LD (7). Increased

awareness among parents and educators

about the academic consequences of

specific learning disabilities, along with

pressures created by rising standards in

schools, may have been additional

factors underlying the increase in the

number of children diagnosed with LD.

Even with the limitations imposed

by discrepancies in parental reports of

diagnosed ADD and LD, the 1997–98

NHIS provides a rich source of

information about these conditions for a

large, nationally representative sample

of school-aged children. Many findings

from the present study confirm results

from previous clinical and communitybased investigations, such as the

significantly higher prevalence of ADD

in boys than in girls (28).

Other findings from the NHIS are

new and show that the associations

between sociodemographic

characteristics and the diagnoses of

ADD and LD vary depending on

whether a child has one or both of these

conditions. Having a diagnosis of
Series 10, No. 206 [ Page 9

ADD/noLD was associated with being a

white non-Hispanic child and having

health insurance. In contrast, having a

diagnosis of LD, with or without ADD,

was linked to being a child in a

low-income or mother-only family. Past

research on ADD and LD has primarily

focused on social and economic

disadvantage as factors related to the

development of these disorders. Few

analyses have considered how health

insurance coverage and higher

socioeconomic status provide access to

health care and facilitate the diagnosis

and treatment of a behavioral condition

such as ADD. If, as most data suggest,

barriers to diagnosis and treatment are

greater in health care systems than in

educational systems, it is not surprising

to find that health insurance coverage

and being a white non-Hispanic child

was associated with ADD/noLD, a

condition often diagnosed by health care

providers, but not with LD, a condition

frequently identified by school personnel

(10). Future longitudinal studies of the

diagnosis of ADD and LD could clarify

how access to health care and the

availability of special education services

influence the likelihood of having either

or both of these diagnoses. Including

measures of ADD and LD based on

assessments of children, in addition to

reported diagnoses, could clarify the

effect of a child’s sociodemographic

characteristics on the development and

identification of these disorders.

Data from the present study also

show a consistent pattern of comorbidity

when diagnoses of both ADD and LD

are taken into account. A comparison of

children with ADD/noLD with children

having a diagnosis of neither ADD nor

LD did not show striking differences in

the prevalence of other health

conditions. A different pattern emerged

when the health conditions of children

with LD (with or without ADD) were

compared with children with neither

diagnosis. A greater percent of children

with LD were reported to have

cognitive, sensory, and other chronic

health conditions. While results from

past studies of LD have indicated a

higher prevalence of other health

problems among children with this

disorder, the results from studies of

ADD have been mixed (29). Data from

the 1997–98 NHIS suggest that knowing

whether a child with ADD also has a

diagnosis of LD is relevant since it may

indicate an increased risk for other

health conditions.

Finally, greater use of a variety of

health care services was reported for

children with diagnosed ADD and/or

LD. Children with ADD (ADD/noLD

and BOTH) were identified as using

prescription medication and mental

health services more often than children

with only LD. The greater use of

medication and mental health services

by children with ADD, reported in the

1997–98 NHIS, is consistent with earlier

results from the 1988 NHIS-CH, which

showed a greater use of health care

services among children with behavioral

problems (30). Results from the

1997–98 NHIS also suggest that the

greater use of health care documented in

a cohort study of children with ADD in

Rochester, Minnesota may be indicative

of greater use of health care by children

with ADD throughout the United States

(31). Finally, the present study indicates

that, among children with diagnoses of

ADD/noLD, LD/noADD, and BOTH,

use of educational and health care

services was generally similar for boys

and girls.

As more years of data are collected

in the NHIS, it will be possible to

expand the analysis of child and family

characteristics associated with the

diagnoses of ADD and LD. Analyses

incorporating characteristics of

communities as well as characteristics of

children and their families may provide

insight into the effect of local health

care and educational practices on the

diagnosis of ADD and LD (32). Finally,

data from the NHIS provide a way to

measure trends in the diagnosis of ADD

and LD and in the use of educational

and health care services by children

with these diagnoses.

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Appendix I

Technical Notes

Source of Data

The NHIS has collected information

since 1957 from U.S. households about

health and use of health care. Each year

a nationally representative sample of the

civilian noninstitutionalized population

is selected and interviewed. Excluded

from the sample are persons residing in

nursing homes or other institutionalized

settings, members of the Armed Forces

(although their dependents are included),

and U.S. nationals living abroad.

Information about the health and

demographic characteristics of each

household member is collected in person

by trained interviewers from the U.S.

Bureau of the Census. Responses for

household members may be obtained by

self or proxy report.

In 1997 the NHIS was extensively

redesigned. The annual NHIS

questionnaire, now called the Basic

Module, collects data from all family

members (Family Core), a sample adult

(Sample Adult Core), and a sample child

(Sample Child Core). The current report

uses data for the sample child contained

in the Family Core and Sample Child

Core. Estimates in this report are based

on information from NCHS in-house

files. Standard errors were calculated

using information about the sample

design available from in-house files. A

detailed description of the NHIS sample

design and survey questionnaires for

1997 and 1998 is available from the

NCHS Web site: http://www.cdc.gov/

nchs/nhis.htm.

Treatment of Unknown Values

Unknown values (responses coded

as ‘‘refused,’’ ‘‘don’t know,’’ or ‘‘not

ascertained’’) for ADD, LD, and the

variables related to other health

conditions and educational and health

care services are not included in the

denominators used to calculate percents.

Unknown values for sociodemographic

variables are not shown in the tables

because of the small number of children

with these responses. Overall, the

percent of unknown values for the

variables presented in this report is low,

less than 1 percent. Two variables have

a higher percent of unknown values:

birthweight (6 percent) and family

income at/above and below $20,000

(4 percent).

Precision of Estimates

The relative standard error (RSE) of

an estimate is used as the criterion of

precision. The RSE was calculated by

dividing the standard error of each

estimate by the estimate itself and

expressing it as a percent. Estimates

with an RSE of 30 percent or greater do

not meet the NCHS standard of

adequate reliability or precision. These

estimates are not shown and are

indicated by an asterisk (*) in the tables

of this report. Standard errors were

calculated using SUDAAN, a statistical

package that adjusts for the effects of

the complex design of the NHIS sample.

Tests of Significance

The test statistic used to determine

whether the difference between two

point estimates is significantly different

from zero was calculated as:

Z = | Xa – Xb | / √ Sa

2 + Sb2

Here Xa and Xb represent two-point

estimates, and Sa and Sb are the

standard errors for these estimates. Point

estimates being compared in this test are

assumed to be independent. The critical

value for a two-sided test indicating a

statistically significant difference at the

0.05 level is 1.96. No adjustments were

made for multiple comparisons.

Appendix II

Definition of Terms

Age—child’s age in years at last

birthday.

ADD—family report of a diagnosis of

Attention Deficit Disorder by a doctor

or health professional.

ADD/noLD—family report of a

diagnosis of Attention Deficit Disorder

without a diagnosis of Learning

Disability.

BOTH—family report of a diagnosis of

Attention Deficit Disorder and Learning

Disability.

Contact with health care provider—

visit or conversation with a physician or

other health professional about the

child’s health.

Developmental delay—significant delay

in one of several areas: physical

development, cognitive (mental)

development, social or emotional

development, or adaptive development.

DSM—Diagnostic and Statistical

Manual of Mental Disorders, the

standard manual for diagnosis of mental

disorders in the United States.

DSM-III-R—revised third edition of the

Diagnostic and Statistical Manual of

Mental Disorders.

DSM-IV—fourth edition of the

Diagnostic and Statistical Manual of

Mental Disorders.

Family structure—parents(s) present in

the household with the child. Mother

and father refer to biological, adoptive,

step, and foster parents.

Family income—wages, salaries,

government payments, child

support/alimony, dividends, help from

relatives, and other sources of family

income during the calendar year prior to

the interview. Each member of a family

is classified by the total income of the

family. Low family income is defined as

an annual income of less than $20,000.

Health care visit—visits to a health care

professional; not including overnight

hospitalizations, emergency room visits,

home visits, or telephone calls.

Health insurance coverage— insurance

coverage at the time of interview

including the following categories:

Medicaid and other related public

insurance (e.g., most State-sponsored

insurance coverage), private and other

types of insurance (e.g., Medicare,

military health insurance coverage, or

another form of government-sponsored
Page 12 [ Series 10, No. 206

health insurance coverage), and

uninsured. Children with only Indian

Health Service coverage are considered

uninsured. Children classified as having

Medicaid coverage include children with

only Medicaid coverage.

IDEA—Individuals with Disabilities

Education Act, Federal legislation

mandating free and appropriate public

education for students with disabilities.

LD—family report of a diagnosis of

Learning Disability by a representative

from a school or a health professional.

LD/noADD—family report of a

diagnosis of Learning Disability without

a diagnosis of Attention Deficit

Disorder.

MSA—metropolitan statistical area, a

county or group of counties containing

at least one city having a population of

50,000 or more plus adjacent counties

that are metropolitan in character and

economically and socially integrated

with the central city.

Central city—largest city in an

MSA.

Not central city—part of an MSA

that is not the central city.

Not in MSA—all other places in the

country.

NEITHER—family report of a

diagnosis of neither Attention Deficit

Disorder nor Learning Disability.

NHIS—National Health Interview

Survey.

NHIS-CH—1988 Child Health Survey,

a supplement to the National Health

Interview Survey.
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 longterm 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 

Monthly Vital Statistics Report (MVSR). These reports provide 

highlights and summaries of detailed data subsequently 

published in Vital Statistics of the United States. Other 

supplements to the MVSR 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: 

Data Dissemination Branch


National Center for Health Statistics


Centers for Disease Control and Prevention


6525 Belcrest Road, Room 1064


Hyattsville, MD 20782-2003


(301) 458–4636


E-mail: nchsquery@cdc.gov


Internet: www.cdc.gov/nchs