Data from the

NATIONAL HEALTH SURVEY

FamilyBackground,Early Development,andIntelligence6-11 Years

UnitedStates

of Children

The relationships of estimated intelligence of these children to

factors in their background, prenatal care, condition of the child

at birth, early developmental history, preschool educational exper-ience, and present medical problems are analyzed.

DHEW Publication No. (HRA) 77-1624

U.S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE

Public Health ServiceHealth Resources Administration

National Center for Health StatisticsHyattsville, Md.

Series 11

Number 142

Vital and Health Statistics-Series 1 l-No, 142Reprinted as DHEW Publication No. (HRA) 77-1624

September 1977

First issued in the Public Health Service Publication Series No. 1000, August 1974

NATIONAL CENTER FOR HEALTH STATISTICS

DOROTHY P. RICE, Director

ROBERT A. ISRAEL, Deputy Director

JACOB J. FELDMAN, Ph.D., Associate Director for Analysis

GAIL F. FISHER, Associate Director for the Cooperative Health Statistics System

ELIJAH L. WHITE, Associate Director for Data Systems

JAMES T, BAIRD, JR., Ph.D., Associate Director for International Statistics

ROBERT C. HUBER, Associate Director for Management

MONROE G. SIRKEN, Ph. D., Associate Director for Mathematical Statistics

PETER L. HURLEY, Associate Director for Operations

JAMES M. ROBEY, Ph.D., Associate Director for Program Deve~opment

PAUL E. LEAVERTON, Ph. D., Associate Director for Research

ALICE HAYWOOD, Information Officer

Library of Congress Catalog Card Number 74-2102

CONTENTS

Page

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

Sources and Limitations ofData . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Findings . . . .’. . . . ; . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . 3Family Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Parent Education . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Relation to First Parent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4Birthplace of Mother . . . . . . . . ..0... . . . . . . . . . . . . . . . . . . . . . . . . . . 5AgeofParents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Family Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... . . . . . . . . 5Age Order . . . . . . . . . . . . .’ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Prenatal Care, Co.mplications. . . . . . . . . . . . . . . . . . . . . . . . ..O . . . . . . . . . 9Condition ofChildat”Birth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Birthweight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Length of Hospitalization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10CongenitalMalformations and Birth Injury . . . . . . . . . . . . . . . . . . . . . . . 10Handedness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Twin Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ~~

Early Developmental History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Change from Breast Feeding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Walking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Speech . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11LearningSpeed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Healthatl Year . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Medical Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Medical History ofNeurological Problems . . . . . . . . . . . . . . . . . . . . . . . . 12Medical Findings on Examination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Preschool Educational Experience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Family Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... 15Condition ofChildatBirth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16Early Developmental History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Medical Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Preschool Experience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 20

...Ill

Page

Lkt of Detailed Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Appendix I. Statistical Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35The Survey Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Reliability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36Sampling and Measurement Error . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36Small Categories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Appendix II. Demographic and Socioeconomic Terms . . . . . . . . . . . . . . . . . . 38

Appendix HI. Household Questionnaire and Medical History Items . . . . . . . . 40

iv

SYMBOLS

Data not available ---------------------------------------- ---

Category not applicable ------------------------------- ., .

Quantity ~e~o ---------------------------------------------- -

Quantity more than O but less than 0.05 ----- 0.0

Figure does not meet standards ofreliability or precision ------------------------------ *

v

FAMILY BACKGROUND, EARLY DEVELOPMENT,

AND INTELLIGENCEOF CHILDREN 6-11 YEARS

Jean Roberts and Arnold Engel, M.D., Division of Health Examination Statistics

INTRODUCTION

This report contains national estimates of theprevalence of selected congenital and earlydevelopmental health problems and describesthe relationship of selected aspects of familybackground, infant health status, and earlydevelopmental history to the intellectual devel-opment and maturity of noninstitutionalizedchildren 6-11 years of age in the United States,based on findings from the Health ExaminationSurvey of 1963-1965.

The Health Examination Survey is a majorprogram of the National Center for HealthStatistics which was established to carry out theHealth Survey Act of 1956, enacted by the 84thCongress to provide for a continuing assessmentof the health status of the U.S. population.

Three different programs are utilized in theNational Health Survey. 1 The Health InterviewSurvey collects health information from samplesof people by household interview. The HealthResources programs obtain health data as well ashealth resource and utilization informationthrough surveys of hospitals, nursing homes andother resident institutions, and the entire rangeof personnel in the health occupations. TheHealth Examination Survey, from which thenational estimates in this report were obtained,collects health data by direct physical examina-tion, tests, and measurements performed onsamples of the population.

The Health Examination Survey has beenconducted as a series of separate programs, orcycles, which were limited to some specificsegment of the noninstitutionalized population

and to specific aspects of health. In the firstcycle, data were obtained on the prevalence ofcertain chronic diseases and the distribution ofvarious physical and physiological measures orcharacteristics in a defined adult population.2 >3

,In the second cycle, on which this report isbased, a probability sample of the Nation’snoninstitutionalized children 6-11 years of agewas selected and examined. The examination,which focused primarily on health factors re-lated to growth and development, included anexamination by a pediatrician, an examinationby a dentist, tests administered by a psycholo-gist, and a variety of tests and measurements bytechnicians. Prior to the examination, demo-graphic and socioeconomic data on householdmembers as well as medical history, behavioral,and related data on the child to be examinedwere obtained from one of the parents, usuallythe mother. Ancillary data for the child on gradeplacement, teacher’s ratings of his behavior andadjustment, and health problems known to theteacher were requested from the school. Birthcertificates for verification of the age andinformation related to the child at birth werealso obtained. The survey plan, sample design,examination content, and operation of thisprogram have been described in detail previ-ously.4

Field collection operations for this cyclestarted in July 1963 and were completed inDecember 1965. There were 7,119 children, or96 percent, examined out of the total probabil-ity sample of 7,417 children selected. Thisnational sample is representative, and the groupof examinees is also closely representative of the

1

nearly 24 million noninstitutionalized children6-11 years of age in the United States at thetime of the survey.

Statistical notes on the survey design, reli-ability of the data, and sampling and measure-ment error are shown in appendix I. Demo-graphic and socioeconomic terms are defined inappendix II.

SOURCES AND LIMITATIONSOF DATA

Background information on the families ofthese children that included family size, positionof mother in the household, and educationallevel of the parents was obtained in a standard-ized interview by the U.S. Bureau of the Censuspersonnel during the selection of the sample tobe examined.

Medical history information–regarding pre-natal care, complications during pregnancy,place of birth of child, length of hospitalizationafter birth, birthweight, twin status, handedness,early developmental history, infant healthstatus, health history of neurological conditions,and preschool educational experience—was ob-tained from a self-administered questionnaireleft in the home of the sample child by theCensus interviewer. The forms were completedby the parent, usually the mother, and pickedup about 2 weeks later by the Health Examina-tion Survey (HES) field representative. Duringher visit to tlie home, the HES field representa-tive reviewed the history and answered questionsthat the parent may have had concerning thatform.

Information available from the birth certifi-cate for more than 94 percent of the examinedchildren included birth order of the child,birthplace of the mother, other children of thismother now dead or stillborn, age of mother andfather at the time of this birth, pregnancycomplications, place of birth, birthweight, andtwin status, and that for about 60 percent of theexamined children included information on con-genital malformation and birth injury.

Questions used from the household interview,medical history, and birth certificate are shownin appendix 111.

Data on congenital heart disease and neuro-logical and musculoskeletal conditions present

and detected at the time of the survey wereobtained from the diagnostic impressions of thesurvey pediatrician based on the findings of hisexamination and on evaluation of the medicalhistory, as described previously.5

Estimates of the intellectual developmentlevels of these children were based on thefindings from the Vocabulary and Block Designsubtests of the Wechsler Intelligence Scale forChildren (WISC), which had been administeredduring the psychological part of the examinaticu,by the survey psychologists in a uniform man-ner, as previously described.6 The Vocabularyand Block Design subtests of the WISC wereselected from the Verbal and Performance testgroups, respectively, since previous studies indi-cated that they were at least as good as any 2 ofthe 12 subtests of the WISC in estimating FullScale intelligence from that test.6

A more thorough evaluation of the adequacyof these two subtests of the WISC in theestimation of Full Scale Intelligence Quotient(IQ) of children 6-11 years of age was made byDr. Jane Mercer of the University of Californiaand the California State Department of MentalHygiene under contract with the National Cen-ter for Health Statistics. Findings from thisstudy among 1,310 children attending publicelementary schools in Riverside, California, in1967-1968 showed that the dyad of subtestsused in the national survey produced predictionsof Full Scale IQ that were better or at least asgood as any other dyad of the WISC across allthree ethnic groups in the Riverside sample. Thecorrelation of Full Scale with the Vocabulary-Block Design dyad determined either as amultiple correlation from the two subtests or asa simple correlation with the sum of the (scaled)scores from the two subtests was +0.88.7

For convenience in this report, raw scores onthe Vocabulary and Block Design subtests forchildren at each single year of age have beenconverted to standard scores by setting the meanobtained in this study at 100 and the standarddeviation at 15. The estimates for the Full Scaledeviation IQ from both subtests combined inthis report were derived by adding the standardscores on the two subtests and again making ascale transformation setting the mean at 100 andstandard deviation at 15. Except for the stand-ardization within l-year rather than 4-month ageintervals and the use of standard scores rathef

2

than scaled scores, the methods used here areidentical to those described in the two previouspublications on WISC findings among chil-dren.G)8 This was done so that the standardscore values would be in units more nearlycomparable to those from the modifiedGoodenough-Harris Drawing Test.

Intellectual maturity level estimates for thesechildren were based on findings from the modi-fied Goodenough-Harris Drawing Test. As in thepreviously published findings from thk test inthe national survey among children, raw scoreson the Man and Woman Scales have beenconverted to standard scores with a scale trans-formation to a mean of 100 and standarddeviation of 15.9~10

These standard score or deviation IQ valuesmake possible the comparison of children of oneage with others of different ages, since these aremeasures which theoretically remain invariantwith age on retest for a particular child unlesshis actual test performance as compared with hispeers changes.

FINDINGS

Family Background

Previous reports from this national study haveconsidered the relationship of education of thefirst parent (for 84 percent, this was the fatherof the child) and of family income to the levelof intellectual development and intellectual ma-turity of U.S. children 6-11 years of ages ~10 Astrong positive association was found with eachsocioeconomic factor. The degree of associationwas substantially greater for intellectual develop-ment as measured by the short form of theWISC than for intellectual maturity as measuredby the modified Goodenough-Harris DrawingTest (HFD). On both tests the association wasslightly greater with parent education than withfamily income. For the WISC the correlation ordegree of association (r) with education wasI-.48 and with income +.43. For the HFD testthe correlation with education was +.24 andwith income +.20. The associations werestronger on the Vocabulary than on the BlockDesign subtests of the WISC. When the effect ofincome is held constant, the degree of associa-tion between parent education and intelligenceof these children is only slightly reduced because

of the strong relationship existing betweeneducation and income (r = +.58).

In this report the relation of additionalaspects of family background to intelligence willbe considered, including educational level ofboth parents, whether both parents are living inthe household, whether the mother was foreignborn, ages of both parents at the time thesechildren were born, other children in the familynot now living, family size, and age order of thechild in the family.

Parent education. –The strong positive rela-tionship between education of the first parent inthe household and intelligence of the child isclearly evident on each aspect of intelligence asmeasured in this study. The mean standard scoreor deviation IQ on the WISC increased consist-ently from 86 among those whose first parenthad less than 5 years of formal schooling to 108among those whose parent had some collegeeducation (table 1). The association was strongeron the estimate of verbal intelligence as obtainedon the Vocabulary subtest of the WISC, wheremean standard scores increased from 84 amongchildren whose first parent had less than 5 years’schooling to 110 among those whose parent hadsome college education, than on the estimate ofintellectual performance from the Block Designsubtest of the WISC, where the mean standardscores increased with parent’s educational levelfrom 90 to 107.

On the measure of intellectual maturity fromthe modified Goodenough-Harris Drawing Test,the consistent association of parent’s educationwith intelligence of the child, although of alower order of magnitude, is clearly evident,with the mean deviation IQ increasing from 90among those whose first parent had the leasteducation to nearly 105 among those whoseparent had some college education. The patternis similar whether the child drew the figure of aman or a woman on this test.

The pattern of association between educationof the second parent (for 86 percent of thechildren, the mother) and intelligence of thechild is essentially identical to that found withrespect to the education of the child’s firstparent. The mean deviation IQ of these childrenincreased consistently on the WISC from 86 to108 and on the HFD from 90 to 104, as theeducation of the second parent increased fromless than 5 years to 13 years or more (table 1).

-.. 3

.

The educational levels of the first and secondparent of the child tend to be similar (r= +.90).Within the four broad educational groups con-sidered here, for 60 percent both parents werewithin the same group, for 18 percent the firstparent was one level advanced, for 17 percentthe second parent was one level advanced, whilefor only 5 percent was there more than one leveldifference between the two parents.

When the educational level of the first parentis held constant and that of the second parentallowed to vary, the positive pattern of associa-tion of the latter with the standard scores of thechild may be seen to persist consistently on theVocabulary subtests within each educationalgroup for the first parent, on the Block Designfor those whose first parent had 5 years or moreof schooling, and on the HFD when limited tofirst parent with 5-12 years of formal schooling(table 2 and figure 1).

Thefather’s

pattern of association between theand mother’s education and the intelli-

gence of their children is essentially identical tothat indicated above for the first and secondparent of these children.

Relation to first parent. –For the majority ofthese children (84 percent) the first-listed parentin the household was the father, while for nearly10 percent the mother was the only parent. Lessthan 1 percent were living with unrelated fosterparents or guardians. Children whose father orstepfather was in the household or whosemother was the only parent generally obtainedhigher mean scores than those living with grand-parents, other relatives, or foster parents, as maybe seen in table A for findings from the HFDtest. The pattern is somewhat more consistentfor those drawing the Man than the Womanfigure, though the difference between the meansc;res” on th; two scales is negligible.

120

110

gz 1000i=asunz<w$

80

0

Under5

)*./”

A...:”:4 ‘“ ./

u- ‘. ,,.~.

EDUCATION OF FIRST PARENT (YEARS OF SCHOOLING COMPLETED)

I.aas 5-S 9-12 13 or

than 5 iore

5.8 9-12

I ILess S-8 8-12 13 or

than5 m<re

t +Lass 5.8 8-12 13 or—

than5 more

13 andover

4’//“./’-.-. --.-.+

— WISCVocabulary.---- WISCBlockDesign---- HFD

EDUCATION OF SECOND PARENT (YEARS OF SCHOOLING COMPLETED)

I I~esa 5-8 8.12 13 orthan5 more

‘igure 1. Mean daviation IQ on tha WISC Vocabulary and Block Dasign and the HFD tests for childran 6-11 years, by educationalattainment of first and aacond parent: United States, 1963-1965.

Table A. Number of children, percent of children, mean standard scores, and standard error of scores on the Goodenough-Harris

Drawing Test for children 6-11 yaars, by relation of first parent to child: United States, 1963-1965

Relation of first parent to child

Father . ., . .,, ,,, . . . . . . . . . . . . . . . . . . .

Mother . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Stepfather . . . . . . . . . . . . . . . . . . . . . . . . . .

Stepmother . . . . . . . . . . . . . . . . . . . . . . . . . .

Grandfather . . . . . . . . . . . . . . . . . . . . . . . . .

Grandmother . . . . . . . . . . . . . . . . . . . . . . . .

Otherrelativa . . . . . . . . . . . . . . . . . . . . . . . .

Unrelatedguardian . . . . . . . . . . . . . . . . . . . . .

Fosterparent . . . . . . . . . . . . . . . . . . . . . . . .

Numberof

children in

thousands

20,083

2,327

723

4

187

124

125

16

195

i Unreliable estimates, included only for completeness,

Birthplace ofmother. –Children6-ll years ofage whose mothers were born in a foreigncountry obtained significantly lower meanstandard scores on the Vocabulary subtest of theWISC than those whose mothers were born inthis country (87 compared with 100); whileonthe Block Design subtest and the HFD test, themean differences were small enough to beduetosampling variability alone (table 3andfigure 2).These findings are similar among boys and girlsbut are less consistent by age because of thesmall number of children with foreign-bornmothers (3.4 percent). The poorer performancefor those with foreign-born mothers on theVocabulary subtest is most evident among theyoungest children at ages 6 and 7; while on theBlock Design subtest, this is apparent onlyamong those at age 6. Among older children, onthe WISC and the HFD tests, the mean differ-ences were small enough to be due to samplingvariability alone.

Age of parents. –Mean deviation IQs of chil-dren 6-11 years of age in the United Statesincreased consistently with their mother’s age atthe time they were born, reaching their maxi-mum values for those whose mothers had been25-39 years. On the measure of intellectualdevelopment (wISC), the increase was from amean standard score of 95 to 101; while on themeasure of intellectual maturity (HFD), meandeviation IQ increased only 3 points from 98 toslightly over 100 (table 4 and figure 3). Only on

Percent of

children

84.4

9.8

3.1

0.0

0.8

0.5

0.5

0.1

0.8

Goodenough-Harris Drawing Test

Mean standard scores

Man

Scale

101.097.8

100.2

‘ 99.4

94.8

92.1

90.5

‘ 93.0

96.6

Woman

Scale

101.0

98.6

96.6

97.5

92.4

92.3

‘113.1

95.2

Standard error

Man

Scale

0.64

1.06

1.61

] 70.27

2.46

5.66

3.45

‘ 65.77

2.11

Woman

Scale

0.48

0.88

1.77

4.42

3.70

3.50

‘ 56.98

3.93

the WISC were successive mean differencesbetween maternal age groups 10-19 years and20-24 years large enough to be statisticallysignificant at the 5-percent probability level.

Only negligible variations in mean deviationIQ of children over the maternal age span 25-39years were evident; while among children whosemothers had been 45 years or over, meandeviation IQ’s on both measures declined totheir lowest point, 90 on the WISC and 91 onthe HFD. Because of the small number ofmothers in these older age groups, the meandifferences in deviation IQ of their children weresmall enough to be due to sampling vanabilityalone, i.e., not statistically significant at the5-percent probability level. The decline wasslightly sharper on the Vocabulary than on theBlock Design subtest of the WISC and on theWoman than on the Man Scale of the HFD.

The pattern of increase in mean deviation IQof children with paternal age at childbirth isgenerally similar to that with maternal age onboth measures of intelligence. However, on theWISC the mean values varied between 100 and101 over the paternal age span of 25-44 years.On both tests the decline in the older (paternal)age groups was slightly less than that found withmaternal age and the differences between thefindings on the two subtests and two scales wereless marked.

Family size. –The intelligence of children 6-11years of age in this country, both on the

5

WISCVocabulary WISC Block Design HFD110-

P11

It#------ 4

.“100- -

● #o*

/ ● ~

1

/,P-”

gp’

.’

~

4’f

G If

; 90- -I

0 ~ -. $’z$ ,P”

z

,./’”

80- .~

+

o 1 1 I 1 I6789101112 6789101112 6789101112

AGE IN YEARS

Figure 2. Mean deviation IQ on the WISC Vocabulary and Block Dasign and the HFD tests for children 6-11 years, by place of birth of

mother and age of child at time of survey: United Statas, 1963-1965.

‘o

— Native-born mother

--- Foreign-born mother

IMother

— Wlsc

100- - --- HFD

,.0d

95- -

90- -

10 20 30 40 50

IFather

10 20 30 40 60

AGE OF PARENT AT TIME OF CHILO’S BIRTH

Figure 3. Mean deviation IQ on the short form of the Wechsler Intelligence Scale for Children (WISC) and on the modified

Goodenough-Harris Humeri Figure Drawing (HFD) tests for children 6-11 years of age, by aga of parants at time of child’s

birth: United States, 1963-1965.

6

measures of intellectual development (WISC)and intellectual maturity (HFD), was found todecrease consistently as the number of otherchildren in the household increased. Mean devia-tion IQs on the WISC decreased nearly 13points, about 0.8 standard deviation, from 103for children in families with one additional childto 90 for those in families with seven or moreother children (table 5 and figure 4). On theHFD test the decline was less rapid: meandeviation IQ’s dropped less than 8 points, theequivalent of 0.5 standard deviation, from themaximum on that test of nearly 102 for childrenin families with two other children to theminimum of 94 for those in families with sevenor more other children. Mean differences inperformance cm the WISC were also largeenough to be statistically significant betweenchildren in families with two-three and three-four other children and on the HFD betweenthose in families with two-three others.

On the subtests, the decrease was greatest onthe WISC Vocabulary subtest, a mean differenceof 17 standard score points, and least on theother three, 8 points on the WISC Block Designand Man Scale (HFD) and 7 points on the

Only children and those with one other childin the family obtained larger mean standardscores (4 points greater) on the Vocabulary thanon the Block Design subtest of the WISC, whilethe reverse was found for those from largerfamilies of four or more other children. Only forthose in families with two or three otherchildren were the mean standard score differ-ences so small they could easily be due tosampling variability alone, i.e., not significant atthe 5-percent probability level. The findings onthe two scales of the HFD test with respect tothe family size were less consistent than thoseon the WISC subtests, although children withone other sibling rated significantly higher onthe Man than on the Woman Scale. Onlychildren and those with three or five siblingsobtained mean scores that weqe slightly greateron the Man than on the Woman Scale, while inother sized families, the reverse was found.

Children from families of no more than threeother children obtained higher mean standardscores on the WISC than on the HFD tests, whilethe reverse was found among those from largerfamilies. Mean differences were large enough tobe statistically significant onlv for families of

Woman Scale (HFD). ‘ “ one, five, and ~ix ;ther children.

105 - -

95- -

85 “-

.-’

,~1 2 3 4 5 6

NUMESER OF CHILDREN UNDER 20 YEARS IN HOUSEHOLD

WISC Vocabulary

HWISC Block Oesign

•1 HFO

7 8 or more

Figure 4. Mean deviation IQ on the WISC Vocabulary and Block Design and the modified HFD tests for children 6-11 years, by

numbar of children under 20 in the household: United States, 1963-1965.

7

The negative relationship of intelligence andfamily size was stronger for boys than for girls asmeasured on the WISC, a mean decrease of 13standard score points for boys (from a mean of103 for those in families with two other childrento 90 for those in families with seven or moreother children) compared with 10 points forgirls (from a mean of 101 for those in familieswith two other children to 91 for those infamilies with seven or more other children). Therelationship and sex difference on the WISCVocabulary subtest findings were substantiallygreater than those on the WISC Block Design.

The mean differences in deviation IQ withrespect to family size for both boys and girlswere lower and more nearly similar on themeasure of intellectual maturity (HFD) than onthat of intellectual development (WISC), 8standard score points for boys and girls betweenthose with two other children and those withseven or more other children in the family. Thepattern of relationship on the WISC BlockDesign performance with family size was similarto that on the HFD test, decreasing mean scoreswith increasing family size of 10 points for bothboys and girls.

The positive relationship of education of thefirst parent to the intelligence of the child isfound consistently across all family size groups(table 6). Mean standard scores for childrenwhose first parent had some college educationexceeded those whose parent had less than 5years’ schooling on both subtests of the WISCand the HFD test, regardless of size of thefamily. The mean differences between those inthe highest and lowest educational groups weregreatest on the Vocabulary subtest for childrenfrom families with one or more other childrenand ranged from 21 to 25 standard score points.On the Vocabulary subtest for only children andon the Block Design for those with or withoutsiblings, the magnitude of the mean differenceswere about the equivalent of one standarddeviation, or 15-17 points. On the HFD test thedifferences ranged from 10 to 15 points.

When controlled by educational level of thefirst parent, a consistent pattern of inverserelationship of family size to performance onthe Vocabulary subtest was found within eachparent educational level. The mean difference instandard score points between those in the

smallest and largest sized families was less forthose in families where the first parent had somecollege education (9 points) than for thosewhose parent had 12 years of schooling or less(13-15 points). Differences on the Block Designsubtest and the HFD test were substantiallysmaller and less consistent with family size,ranging from 2-6 standard score points acrossthe four parent education groups.

Children who had one or more older siblingswho had died or were stillborn, prior to thebirth of the child in this study, rated lower onthese measures of intelligence than did childrenfrom families where this had not occurred (table7). However, no significant or consistent trendwas found in relation to the number of suchnonliving older siblings.

Age order. –A significant relationship wasfound between the age order (birth order) of thechildren and their performance on the intelli-gence tests in this study. The mean deviation IQon both the measure of intellectual developmentand that of intellectual maturity decreasedconsistently with the decreasing age order of thechildren, from 101 and 100 among those whowere oldest or only children in the family to 92and 96, respectively, among those 6th or later inage”order (table 8).

The relationship to age order was sub-stantially stronger on the WISC than on theHFD test. On the test parts, the association withage order was also substantially stronger on theVocabulary than the Block Design of the WISCand somewhat weaker on the Woman than onthe Man Scale of the HFD test. The meandecreases on the Vocabulary, Block Design,Man, and Woman test parts between those whowere first and those who were 6th or later were12, 7, 5, and 2 standard score points, respec-tively. This pattern of relationship betweendeviation IQ of these children and their ageorder was generally similar among both boys andgirls.

When controlled by family size (number ofchildren under 20 years in household), thepattern of relationship of intelligence of chddrento their age order in the family is essentiallyeliminated. However, children from smallerfamilies (three or fewer children) rated higher onthese tests than did children from larger families,irrespective of age order. The findings on the

8

two subtests of the WISC, where the pattern isstrongest, are shown in table 9.

As would be expected, irrespective of the ageorder of the child, there was a consistentincrease in mean deviation IQ with increase ineducational level of the parent. The pattern,which was simiksr with respect to the educa-tional level of both first and second parent, wasshown on the WISC with the education of thefirst parent and on the HFD test with theeducation of the second parent (table 10).

Prenatal Care, Complications

The extent of prenatal care and complicationsduring pregnancy for the mothers of thesechildren age 6-11 years in the present nationalstudy have been described in a previous re’port.11 Some prenatal medical care had been

- obtained for more than 97 percent of themothers of these children. Medical problems orcomplications during this pregnancy were re-ported for 13 percent, nearly all of whom hadconsulted a doctor regarding the condition.

No relationship was found between the intell-igence of these children and whether theirmothers had had complications during thispregnancy. The mean deviation IQs on bothmeasures of intelligence were approximately 100for the 13 percent whose mothers had suchproblems indicated on the child’s birth certifi-cate and for the 87 percent whose mothers didnot (table 11). Those whose mothers had ob-tained some prenataI care during this pregnancytested somewhat higher than those whose moth-ers did not, although the differences no longerexisted when the effect of parent education wasremoved.

Condition of Child at Birth

Birthweight. –Available information from themedical history given by the mother for thechildren 6-11 years of age in this survey andfrom the child’s own birth certificate showedthat nearly 3 percent had weighed less than 5pounds at birth, 96 percent between 5 and 10pounds, and the remaining 1 percent more than10 pounds.l 1

Children who weighed between 5 and 10pounds at birth rated higher on the two meas-

ures of intelligence than those who weighed lessthan 5 pounds or more than 10 pounds (table 12and figure 5). Mean differences on the WISCwere 5 and 4 standard score points, respectively,for those who weighed less than 5 pounds ormore than 10 pounds. On the HFD test theywere nearly 4 and 2 standard score points,respectively. Only on the measure of intellectualmaturity (HFD) was the mean difference be-tween the scores for those essentially normalweight at birth and the heavier babies smallenough to be due to sampling variability alone,i.e., not statistically significant at the 5-percentprobability level.

When the more detailed birthweight datafrom the birth certificate are used, the increasein mean deviation IQ with weight (at birth) isslow but consistent up to about 8 pounds, asillustrated in table B for the WISC short-formfindings. For boys this increase was from 89among those weighing less than 3 pounds 5ounces at birth to over 102 for those weighingbetween 7 pounds 12 ounces and 8 pounds 13ounces. Girls showed a similar consistent but

100

95

90

0

r

1

■ “SCm HFD

Under 5“” 5-1o Over 10

pounds pounds pounds

BIRTHWEIGHT

Figure 5. Mean deviation I Q on the short form of the Wfechs[er

Intelligence Scale for Children (WISC) and on the modified

Goodenough-Harris Human Figure Drawing (HFD) tests for

children 6-11 years of age, by weight at birth: United States,

1963-1965.

9

Table B. Mean deviation IQ and standard error of mean on the WISC short form, by birthweight and sex for children

6-11 years: United States, 1963-1965

Birthweight from birth certificate

Lessthan 3 pounds 5 ounces . . . . . . . .3 pounds 5 ounces-4 pounds 6 ounces . .

4 pounds 7 ounces-5 pounds 8 ounces . .5 pounds 9 ounces-6 pounds 10 ounces .

6 pounds 11 ounces-7 pounds 11 ounces

7 pounds 12 ounces-8 pounds 13 ounces

8 pounds 14 ounces-9 pounds 14 ofinces

9 pounds 15 ounces-11 pounds O ounce .

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

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

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

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

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

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

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

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

Deviation IQ

ZcizcMean

89.494.296.2

98.1101.4

102.4

102.0

97.7

90.3

95.1

96.097.098.3

99.9

97.1

97.7

5-.P-Standard error

L

* 1.502.70 1.801.40 1.000.90 0.700.70 0.600.90 0.70

1.30 1.50

1.70 4.10

slightly smaller gain in mean IQ, from 90 to 100 negligible proportion (O.1 percent) ambidex-over the same birthweight span.

Length of hospitalization. –Those childrenwho were kept in the hospital 2 weeks or lessfollowing their birth rated higher on bothmeasures of intelligence, on the average, thanthose who were retained for over 2 weeks. Meandifferences were large enough to be statisticallysignificant on WISC (both Vocabulary and BlockDesign) and on the Woman but not on the ManScale of the HFD test. The group who requiredmore than 2 weeks of hospital care at that time(3 percent of the children) would have includeda large proportion of those born prematurely,with birth injuries, congenitzd malformations,and other medical problems. 11

Congenital malformations and birth injury.–Chddren for whom a congenital malformation ora birth injury was recorded and identified on thebirth certificate obtained somewhat lower meanstandard scores on the WISC (both Vocabularyand Block Design), but not on the HFD test,than those for whom no abnormality was notedat birth. However, the proportion of childrenwho had such conditions was so small, i.e., lessthan 2 percent, that the mean differences instandard Score could easily be due to samplingvariability alone.

Handedness. –Among these children 6-11

years of age at the time of this study, approxi-mately 11 percent were left handed and theremaining 89 percent right handed, with a

trous.Mean deviation IQs for right-handed children

were nearly identical to those for left-handedchildren on both measures of intelligence and onthe four subtests or parts. The substantiallylower mean standard scores for the ambidex-trous group are probably due to samplingvariabilityy alone, i.e., not significant at the5-percent level.

Twin status. –Twins were found to scoreslightly but not significantly lower than thesingle-born children on both the measure ofintellectual development and that of intellectualmaturity. Mean differences in deviation IQbetween nontwins and twins, as well as betweenfraternal and identical twins, were small enoughto be due to sampling variability aIone sinceonly about 2 percent of these children weretwins.

Early Developmental History

Information on the early developmental his-tory of these children 6-11 years of age at thetime of this study–including the age they firststarted walking by themselves or speaking theirfirst real word and the relative speed with whichthey learned to do th’mgs by themselves–havebeen described and analyzed previously, ~2

Change f+otn breast ~eeding.-Children whowere reported by their mothers at the time of

the survey to have had no troubIe accepting thechange from breast feedingl 1 (91 percent ofthose breast fed) generally rated slightly but notsignificantly higher (mean difference of 2-3standard score points) on the survey measures ofintellectual development and intellectual matur-ity than the remaining 9 percent of children whowere reported to have had some or a consider-able problem switching to regular food (table13).

Walking.-The intelligence of children whofirst walked by themselves before the age of 1year was, on the average, similar to that forchildren who did not start walking until 12 to18 months of age. Mean deviation IQ’s on themeasures of intellectual development and intel-lectual maturity were approximately 100 forboth those who started waking etily and thosewho started at the more usual age (table 13 andfigure 6).

However, among children who did not walkalone until after 18 months of age (nearIy 4

105

100

g20i=

95~>:

3z

90

85

0 I I

Wlsc

❑ HFD

fl

Under 12. 12-18 Over 1S

months months months

AGE CHILD FIRST WALKED ALONE

Figure 6. Mean deviation IQ on the short form of the Wechsler- Intelligence Scale for Children (WISC) end on the modified

Goodenough-Harris Human Figure Drawing (HFD) tests forchildren 6-11 years of age, by age child first walkedalone: United States, 1963-1965,

percent of the children), the mean deviation IQin both the WISC and the HFD test wassubstantially lower—about 10 points less thanfor those who walked alone by or before 18months. Mean differences were statistically sig-nificant at the 1-percent probability level onboth tests and the four subtests or parts. Themean difference or lag for this physically re-tarded group was slightly gz-eateron the Vocabu-lary subtest and Man Scale of the HFD test thanon the Block Design subtest and the WomanScale of the HFD test.(12 and 11 standard score,points compared with 8 and 9).

Both boys and girls who started walking laterthan usual were also significantly and similarlyretarded in mean deviation IQ on these intelli-gence tests.

Speech. –ChiIdren who did not speak theirfirst word until after 18 months of age (8percent) were also significantly Iawer in intelli-gence as measured in this survey on either theshort form of the WISC or the modified HFDtest than those who started speaking earlier.Their mean deviation IQ’s on both tests were 7points behind those who started talking beforethe age of 1 year and 5 points behind those whobegan between 12 and 18 months of age (table13 and figure 7). The differences in meanstandard scores among all three groups-thosewho started talking early, at the more normalage, or later–were too large to be due tosampling variabilityy alone, i.e., statistically sig-nificant at least at the 5-percent level. Theextent of retardation in deviation IQ amongthose starting to speak later than usual wasslightly greater on the Vocabulary subtest thanon the other subtests. Among girls and boysthere was a similar pattern of lower intelligencelevels, on the average, among those starting totalk later than usual.

Learning speed. –Mothers’ ratings of the speedwith which their children learned to do thingssuch - as eating or dressing by themselves isgenerally consistent with their children’s laterperformance at ages 6-11 years on these intelli-gence tests at the time of the survey. Thosechildren considered by their mothers as learningfaster than other children had significantlyhigher mean deviation IQ’s on both intelligencetests (scores of 103 on the WISC and 102 on theHFD) than those whose learning speed was

11

gzg

105 =-

100 --

95 --

90 --

85 --/

Wlsc

❑ HFD

I IUnder12 12-18

months months

+

months

AGE CHILD SPOKE FIRST REAL WORD

Fiaure 7. Mean deviation IQ on the short form of the Wechsler

- Intelligence Scale for Childran (WISC) and on the modifiedGoodenough-Harris Human Figure Drawing (H FD) tasts for

children’ 6-11 years of aga, by age child spoka first realword: Unitad States, 1963-1965.

considered average (scores of 99 on both tests).The latter group, with average learning speed,rated substantially higher on these tests thanthose reported to have been slower in learningthan other children (mean scores of 89 on theWISC and 91 on the HFD). These differentialswere found onboys and girls.

all four &btests among both

Health at 1 Year

At the end of their first year of life, 91percent of the children 6-11 years of age werereported to have been in good health, nearly 8percent in fair health, and nearly 2 percent inpoor health, according to the information givenby their mothers at the time of this survey, aspreviously described. 11

Those children whose mothers reported themto have been in good health at L year of agerated significantly higher on both measures of

12

intelligence used in the study” than those con-sidered in fair or poor health at that earlierperiod. The pattern was similar on both tests:the respective mean deviation IQ’s on the WISCby infaht health status were 100, 97, and 93;and on the HFD they were 100, 98, and 93(table 13). The relationship of infant healthstatus to intelligence of children 6-11 years ofage was consistent among both boys and girls onall four subtests.

Medical Problems

Medical hsktory of neurological prob-lems. –The medical histories for the childrenobtained from the mother just prior to theirexamination indicated that 0.3 percent wereknown to have epilepsy and 0.1 percent cerebralpalsy, as previously described.l 8

Those children reported to have cerebral palsytested more than 15 standard score points belowother children, on the average, on each of thetests and subtests of intelligence used in thesurvey (table 14), mean differences that on theWISC and HFD were statistically significant atthe 5-percent probability level despite the lowprevalence of this condition. Those with ahistory of epilepsy also had significantly lowermean deviation IQ’s on these tests than otherchildren, but the mean differences were sub-stantially smaller, 5 standard score points on theWISC and 8 on the HFD.

Medical findings on examination. –From themedical findings on physical examination at thetime of the survey, the prevalence of heartconditions among U.S. children 6-11 Years wasestimated as 2.6 per 100 children and forneuromuscular joint conditions as 3.6 per 100(table 14 and figure 8). In addition 3.6 per 100children were found to have some other type ofmedical condition. These findings were based onthe medical history made available to the ex-amining pediatrician and his own diagnosticfindings at the time of the survey exarnina-tion.ls Information from the birth certificatesavailable for 60 percent of these childrenshowed that a congenital malformation with orwithout a birth injury had been evident at birthfor 1.0 percent and that an additional 0.3percent had a birth injury only. It should bekept in mind that all three sources of infor-mation—the birth certificate, the medical his-

I I

Normal on examination

Congenital heart condition

Acquired heart condition

Cerebralpalsy and other cerebral problems

Mongolism ondlor mental retardation

Eye disorders

h4usculoskeletdjoint conditions only

Io 20 40 60 80 100

PERCENTOF ALL CHILOREN

Figure 8, Percent of children 6-11 years of age, by specific finding on survey physical examination: United States, 1963-1965.

tory, and the examination–are subject to ob-server differences.

The examining pediatrician considered 80percent of the heart conditions and 60 percentof the neuromuscular joint conditions found oridentified on examination in the survey to havebeen congenital.

Those children with congenital heart orneuromuscular joint conditions found or identi-fied on examination scored substantially loweron both measures of intelligence used in thesurvey than children without such physicalconditions and slightly below those whose heartor neuromuscular joint condition was consideredto have been acquired. Mean deviation IQs forthose children with congenital heart conditionswere 5 standard score points below and thosewith acquired heart condition about 3 pointsbelow those without heart conditions on bothtypes of intelligence tests (WISC and HFD).Those children with congenial neuromuscularjoint conditions had mean deviation IQs on theHFD 8 standard score points below and on theWISC nearly 6 standard score points below therespective mean deviation IQs for childrenwithout such conditions (table 14 and figure 9).

A further review of the specific type ofneurological joint conditions indicated that 0.5percent of the children in this study had a

neurological condition identified as cerebralpalsy, other cerebral problem, or minimal cere-bral dysfunction; 0.3 percent were identified onexamination as mongoloid and/or mentally re-tarded, 0.6 percent as having eye muscle dis-orders, and 2.2 percent as having only mus-culoskeletal joint conditions.

Findings from the measure of intellectualdevelopment (WISC) used in the survey showsignificantly lower mean deviation IQs for thosechildren with a condition identified by thepediatrician as mongolism and/or mental retar-dation or as cerebral palsy, other cerebralproblem, or minimal cerebral dysfunction thanfor those children with eye disorders or mus-culoskeletal joint conditions, as may be seen intable 14.

Preschool Educational Experience

On the medical history obtained prior to thesurvey examination of these children 6-11 yearsof age the mother was asked whether the childhad attended kindergarten and/or nurseryschool. Seventy percent of these children werereported to have had such preschool educationalexperience. The mean deviation IQs for childrenwith this experience was significantly greaterthan for those without it, 7 standard score

13

‘orma’”nexam’na””nb~Congemtal heart condwm

Acquwed heart condmon

Cerebral palsy and other cerebral problems

Mongollsm andlor mental retardatmn

Eye disorders

Musculoskeletal joint condwms only

o 75 80 85 90 95 100 105

MEAN DEVIATION IQ

Figure 9. Mean daviation IQ on the short form of the Wechsler Intelligence Scale for Children (WISC) for children 6-11 years of age,

by specific findings on survey physical examination: United States, 1963-1965.

points greater on the WISC and 4 points greateron the HFD. The differential existed on boththe Vocabulary and Block Design subtests of theWISC (mean differences of 8 and 6 standardscore points, respectively) but only on theWoman Scale of the HFD, and on that to a lesserextent (3 standard score points).

When considered in relation to the educa-tional level of first parent for white and Negrochildren, those with preschool educational ex-perience consistently scored slightly higher, 2 to6 standard score points on the average, on theWISC Vocabulary and Block Design subtests andon the HFD test than those without suchexperience at each level of parent education(table 15). The only exception was on the HFDtest for white children whose parents hadcompleted less than 5 years of formal schooling.

The relationship between educational level ofparent and deviation IQ of the child wasstronger on the WISC for white than for Negrochildren but of approximately the same order ofmagnitude on the HFD test for both racialgroups among children with and without somepreschool educational experience. Hence, forchildren of both racial groups, preschool educa-

tional experience does seem to have a slightpositive influence on their standard scores onthese intelligence tests even when the effect ofthe educational level of their first parent is heldconstant.

DISCUSSION

Factors in the family background and earlydevelopmental history of children considered inthis report in relation to their measured intelli-gence will themselves generally be influenced byvarious aspects of both heredity and environ-ment in varying degrees. The contributions ofboth have been the subject of extensive studyfor over half a century Since Binet’s early workwith intelligence testing.1A Studies of twins suchas that of Starr-Salapatekls have attempted toestimate the proportion of variability in generalintelligence scores due to heredity and environ-ment among the advantaged and disadvantaged.However, this report is limited to nationalestimates of the pattern of interrelation of thefactors considered with measured inteKlgence.Comparisons are made insofar as possible withprevious relevant findings among children, al-

14

though almost without exception the previous effect which is essentially independent of thestudies have used tests of intelligence different effect of maternal age for fathers 45 years andand not precisely comparable to those used in older consistent with results from the presentthe present national survey. study. In particular, congenial malformations

were substantially more frequently found amongchildren with older fathers.

Family Background

The strong direct association between boththe intellectual development and intellectualmaturity of U.S. children 6-11 years of age andthe educational attainment of their parentsfound in the present national study are consist-ent with previous findings among those groupsof children studied by Bayleyl 6 and Honzik.17

Younger children in the present study whosemothers were foreign born, and hence wouldhave included a disproportionate number whowere bilingual, rated lower on the verbal but noton the performance tests of intelligence used inthis study than did children of comparable ageof native-born mothers, consistent with thefindings from nearly 100 investigations in theUnited States and other countries with respectto intelligence test scores of younger bilingualversus monolingual children. 18

The pattern of association between maternalage and intellectual functioning of children fromthe present study (lower deviation IQs forchildren whose mothers were under 20 years andthose 40 years and over) is similar to but evenmore pronounced than that found by Lobll 9 atJohns Hopkins in his study of more than 3,000births among mothers from middle and lowersociocultural groups. He attributed the de-pressed IQ’s for children of younger mothers toa number of biological and environmental fac-tors including physiological and anatomic im-maturity influencing maternal reproductive ca-pacity and immaturity of maternal behaviorwith respect to child-rearing practices. Theoccurrence of mongolism and other anomalies ofthe central nervous system he found to bestrongly related to advancing maternal age, withover half of the reported cases of such condi-tions in his study being among children ofmothers 36 years and older.

With respect to the effect of paternal age onintelligence of children, Newcombe and Taven-dalez 0 found, among their study group inBritish Columbia, a significant paternal age

The negative relationship of family size, i.e.,number of live siblings, to the intelligence ofU.S. children in the present study was morepronounced on the verbal than on thel per-formance tests and stronger among those who~~parents had no college education than thosewhose parents did. This relationship is consistent

-21,22 Bajema,23 Hig-with findings of Anastasl,gins,z4 and Nisbet.25 ~z G The relative dif feren-tial in verbal and nonverbal development hasbeen attributed to different degrees of adultcontact provided in families of different size andof different economic levels. However, studies ofDawson27 and O’Hanlonz 8 among some 1,200Glasgow children showed an even stronger nega-tive or inverse relationship between intelligence(Stanford-Binet tests) and family size when allbirths, including stillbirths, were considered thanwhen limited to live siblings in the family. Thisis also consistent with findings from the presentstudy where there is a more marked differencein mean deviation IQ between single childrenand those with one or more stillborn or deceasedsiblings than with one or more live siblings.

The influence of ordinal birth position onmeasured intelligence has been investigated forsome 100 years. Altus,z 9 in a review article,cites analyses of persons in Who’s Who, RhodesScholars, English Men of Science, and similarselect groups showing predominance of the firstborn. Sir Francis Galton in the 1874 EnglishMen of Science suggested that through the lawof primogeniture the eldest son was likely tobecome possessed of independent means and tobe able to follow his own tastes and inclinations.Furthermore, he speculated that parents treatedan only child and a first born as a companionand accorded him more responsibility than otherchildren. More recent findings of Chittenden etal.30 showed differences between siblings ongrades and test scores that significantly favor thefirst born. In the present national study, while asignificant inverse relationship was found be-tween age order and performance on the intelli-gence tests used, the mean difference betweenthe first and second born was negligible.

15

Condition of Child at Birth

Birth weight. –The significantly lower meanlevels of both measured intellectual developmentand intellectual maturity among U.S. children ofbelow and above normal birthweight thanamong those of more normal birthweight (5-1 Opounds) are consistent with findings from avail-able previous studies. Babson et al.,s 1 in hiscollaborative perinatal study among 4-year-oldOregon children, found the mean IQ (Stanford-Binet) of the oversized birthweight group to be3.5 points below those of standard birthweight.

Various studies have been concerned with theeffect of prematurity or low bh-thweight onphysical and mental development. Weiner~ zindicated in his review of available studies priorto 1962 that of the 18 studies reported, onlyone failed to find premature subjects at adisadvantage in regard to IQ. More recent studiesof Weiner et al.38 ~3A have indicated that impair-ment (intellectual) in low birthweight infants islargely due to associated measurable indexes ofminimal neurological involvement. Retardedgrowth in premature babies has been attributedin many cases to the effect of placental insuffi-ciency. Yoshida et al.3s recently demonstrate edan altered pattern of energy metabolism inleukocytes of premature (small for gestationalage) infants similar to that found in younginfants with severe postnatal protein-calorie mal-nutrition, thus lending support to the concept

that fetal growth retardation may be a manifes-tation of malnutrition Z%utero. On autopsy of agroup of small-for-gestational-age and normalbirthweight infants, Chase et al.3 G found thecerebellum to be the area of the brain mostgreatly affected by intrauterine under-development.

Congenial malformations and birth injuries.–Since the population under study excludesimstitutio~alized children, the lack of a demon-strable association between measured intelli-gence and the presence or absence of a congeni-tal malformation or injury identified at ~he timeof birth for U.S. children is not unexpected,with the low prevalence of such conditionsrecorded on the birth certificate. The 1970report of a WHO Scientific Group on GeneticFactors in Congenital Malformations,3 T in sum-marizing available research findings, indicates

that about 1 percent of all liveborn and stillbornchildren have or will develop signs of a harmfulsingle-gene trait and that a further 1 percenthave chromosomal abnormalities, many ofwhich determine severe handicaps. In addition,some 3-4 percent of all liveborn and stillbornchildren have congenital malformations, as de-fined by the WHO group, although, as many ofthese affect internal organs, they may not berecognized until long after birth or at autopsy.These WHO estimates are generally COI&kIIL

with those for U.S. children from the presentstudy. In a small proportion, the WHO reportindicated there is a known teratogenic agent—e.g., maternal rubella, toxoplasmosis, or ex-posure in early intrauterine life to ionizingradiation or to toxic agents or drugs. However,the majority of such conditions have a geneticcomponent, and almost all have indirect evi-dence of an environmental component also.

Twin status.–National estimates from thepresent study showed twins to have ratedslightly but not significantly lower, on theaverage, than the single-born child on the verbalcomponent of the test of intellectual develop-ment (wISC-Vocabulary) and on the test ofintellectual maturity (HFD). On the perform-ance component of intellectual development(WISC-Block Design) twins did as well as non-twins.

These findings are somewhat less marked thanthose of Mittler3 S and Record, McKeown, andEdwardss g in England and Husen40 in Sweden.Mittler, in his study of 4-year-old English chil-dren (200 twins and 100 singletons), found thetwins to be more retarded than the nontwins inlanguage development and also found someindication of overall immaturity. Record,McKeown, and Edwards, in their study ofBirmingham children (48,9 13 single born and2,164 twins), showed twins to do less well onthe standard “eleven-plus” test of verbal reason-ing than nontwins. They attributed this primar-ily to less frequent association of twins withadults. Husen, in his study among 2,700 singlebores and 1,000 twins in Sweden, found thattwins did not do as well on achievement testsand in school marks as the single born.

Much of the difference between findings fromthe present study among U.S. children and thosefrom the English and Swedish studies is prob-

16

ably due to the lack of comparability of thetests used.

Early Developmental History

Walking.–The strong association between de-layed walking (starting after 18 months) and theintellectual development and maturity of U.S.children in the present study is consistent withprevious findings among various groups in thepopulation. Donoghue et al.41 found that only11 percent of English children in a ward for thementally retarded had learned to walk beforethe end of the second year compared with 95percent of infants from a well-baby clinic whowalked unaided by age 10-14 months. Neliganand PrudhamA z found from the NewcastleSurvey of Child Development that children laterexcluded from normal school because of mentaldefect, cerebral palsy, or deafness showed asignificant delay in walking unaided.

Speech. –The relationship between intelli-gence, as measured in this study, and theretardation of speech development is nearly asstrong as that between intelligence and walking.This also would have been expected since themajor causes of speech delay have generally beenfound to be mental retardation, functional(emotional), brain injury, and hearing 10SS.43)44In the Newcastle Survey4 z Neligan and Prudhamalso found that children later excluded fromnormal school on account of mental defect,cerebral palsy, or deafness showed a significantdelay in using sentences.

Children in the present national study witharticulation problems (8 percent of all children)also had lower standard scores on these intelli-gence tests than those whose parent indicatedthey had no trouble talking. This is consistentwith findings of Martyn, Sheehan, and Slutz45for mentally retarded p’atients in a Californiahospital where nearly one-third had articulationdisorders.

Medical Problems

Conditions affecting the development or func-tioning of the nervous system, primarily cerebralpalsy and epilepsy, have been found repeatedly

to be more prevalent among the mentallyhandicapped ~ha.n among the general pop-ulation.Az‘44 )46 In particular, Drillien et al.,46in their studies of the mentally handicappedchildren in Edinburgh, in and outside of institu-tions, found over one-half to have cerebral palsyand about one-sixth to have epilepsy.

While the present study among U.S. childrenis limited to the noninstitutional population andhence excludes a substantial proportion of themore severely mentally handicapped in thiscountry, the relation of these conditions tomeasured intellectual development and maturityis clearly apparent. Those U.S. children with ahistory of cerebral palsy, though varying sub-stantially in performance, obtained mean stand-ard scores on both intelligence tests that weremore than 1 standard deviation below the meanfor all children (16 and 21 standard score pointslower, respectively); while those with a historyof epilepsy, who also varied widely in perform-ance, as a group tested one-third to one-half astandard deviation below the mean for allchildren (5 standard score points on the WISCand 8 on the HFD). Those with a history ofepilepsy, but not the cerebral palsied, were lessretarded on the Block Design than the Vocabu-lary subtest of the WISC.

For children with cerebral palsy and epilepsy,the presence or extent of mental deficiencywould depend on the area of and degree towhich the brain was affected.

Cerebral palsy-the group of conditions af-fecting control of the motor system due tolesions in various parts of the brain and occur-ring as a result of birth injury or prenatalcerebral defect–is more frequently associatedwith severe mental deficiency.

As summarized recently by Stores,47 previousresearch on the cognitive function in childrenwith epilepsy (among whom proportionatelyfewer appear to be mentally impaired) indicatesthat among persons with epilepsy temporal lobelesions in the hemisphere dominant for speechcause impairment of verbal abilities (includingdefects of retention and learning of verbaImaterial); while performance on tests of visuo-spatial or perceptual-motor abilities and ofmemory for nonverbal material is impaired bylesions of the temporal lobe in the nondominant.hemisphere.4 8‘53

17

‘4

In contrast with patients with temporal lobeattacks, those with “centrecephalic” epilepsyhave been shown to have no obvious memorydefect, but to be impaired on tests of sustainedattention.54

In further recent research on the comparativeperformance of noninstitutionalized epilepticand nonepileptic children, Green and HartlagesGconcluded that the reason epileptic childrenscored below expectancy levels in schoolachievement and language usage may be thatparental expectations tend to be lower for themthan if they were not epileptic. This hypothesiswould be consistent with the poorer perform-ance among U.S. children shown on the Vocabu-lary than on the Block Design subtests of theWISC from the present study.

Previous studies have suggested that children ‘with significant congenital heart defects, espe-cially of the cywotic type, may have delayedmotor development and a higher-than-expectedincidence of mental subnormalityys6-59 consist-ent with findings from the present study amongU.S. children. Findings from these earlier studieswere mixed with respect to the influence ofhemodynamic severity of the lesion, but severalsuggest that environmental deprivation due tophysical incapacity may be a factor.

Preschool Experience

The slight advantage evident in this study onthe measures of intellectual development andintellectual maturity of children who had somepreschool educational experience, such as that inkindergarten or nursery school, over those whohad none is not inconsistent with findings fromseveral previous studies.

McHugh,G0 in his 1940 study of childrenentering public school kindergarten in a smalltown in New Jersey, found significant gains inIQ score resulting from preschool experiencewhen the Stanford-Binet tests were given understandard conditions and when the initial test wasgiven before any preschool experience. Hefurther concluded that since these gainsoccurred so rapidly it was more likely they weredue to better adjustment of the testee in the testsituation than any real growth in intellectualcapacity.

Earlier studies ofWellman61 at the Universityof Iowa Child Welfare Research Station found

that length of preschool experience beyond 1year bears a direct relation to the amount ofgain in intellectual capacity.

In a number of reports from established childresearch centers throughout the United States—including those of Anderson,G Z Bayley,63 ~64Bird,G5 Frandsen and Barlow,G6 Goodenoughand Maurer,6T Lamson,68 Olson and Hughes,6 gand VoasT0—the investigators were unable toconclude from the results of their researchesthat preschool experience has any appreciableeffect upon the IQ.

A subsequent study by Wellman and McCand-less71 at the Iowa Child Welfare ResearchStation found evidence suggesting that teachercontacts at the station preschools play a definiterole in the verbal aspects of mental develop-ment, particularly of children in their first yearof preschool experience, but that verbal aspectsof intelligence are not the aspects in whichpreschool is most stimulating to IQ change.

More recently Cicarelli et al.,7 z in theirevaluation of the effect of the Head Startprograms, found slight but statistically signifi-cant superiority of full-year Head Start childrenon certain measures of cognitive development.In their review of the existing evaluative studies,they also found that these preschool curriculaachieve little unless they focus on language andnumber concepts.

SUMMARY

This report contains national estimates of theprevalence of selected congenital or other earlydevelopmental health problems and describesthe relationship of selected aspects of familybackground, infant health status, and earlydevelopmental history to the intellectual devel-opment and maturity of noninstitutionalizedchildren 6-11 years of age in the United States,based on findings from the National HealthExamination Survey of 1963-1965. For thisnational study, the probability sample of 7,417children selected was representative, and the7,119 (96 percent) examined were closely repre-sentative of the 24 million noninstitutionalizedchildren 6-11 years of age at that time.

The measures of intellectual developmentused were the short form of the WISC (Vocabu-lary and Block Design) and the modified HFDtests.

The principal findings from this study are that

●

●

●

●

The relationship between intellectual devel-opment or intellectual maturity of childrenand the academic achievement of theirsecond parent, or mother, was as strong asthat previously found for this group withthe educational level of their first parent,or father.

Children 6-11 years of age whose motherswere foreign born generally did as well aschildren whose mothers were natives of thiscountry on the tests of intellectual develop-ment and intellectual maturity used in thisstudy except for younger children on theverbal component (wISC-Vocabulary).

Mean deviation IQ scores of these children6-11 years of age increased with the age oftheir mother and their father at the time oftheir birth to a maximum at 25-39 yearsfor maternal age and 25-44 for paternalage. Those whose parents had been older,40 years or more for the mother and 45years or older for the father, showed lowermean scores than those whose parents hadbeen younger at the time these childrenwere born.

The intelligence of children (mean de-viation IQ) on both measures used in thisstudy was found to decrease consistently asthe number of other live children in thefamily increased. When controlled on edu-cational level of the first parent, thatpattern of indirect association with familysize on the WISC Vocabulary subtest per-sisted but was less marked or consistent on

●

●

●

●

●

either the WISC Block Design or themodified HFD.

Children who were of relatively normalweight at birth, 5-10 pounds, rated signifi-cantly higher on both measures of intelli-gence used in this study than those whoweighed under 5 pounds or more than 10pounds.

Twins were found to score slightly but notsignificantly lower than single-born chil-dren on both measures of intelligence.

Children whose walking or speech wasretarded beyond 18 months of age showedsignificantly lower mean deviation IQ’s onboth measures of intelligence.

Prevalence estimates for medical conditionsspecifically identified on examination orhistory for these noninstitutionalized U.S.children 6-11 years of age including epi-lepsy, cerebral palsy, mongolism, eye-muscle disorders, and heart and musculos-keletal joint conditions were obtained.Those children with such medical condi-tions tended to show significantly lowermean deviation IQ scores than childrenwithout these problems.

Children with some preschool educationalexperience—i.e., who-had attended kinder-garten or nursery school–generally showedsome advantage in deviation IQ scores overthose without such preschool training evenwhen the effect of the educational attain-ment of their parent(s) was held constant.

Comparisons with relevant findings from pre-vious available studies are included.

19

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20

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31 Babson, S. G., Henderson, N., and Clark, W. M.: Thepreschool intelligence of oversized newborns. Pedtitrics

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40 Husen, T.: Abilities of twins. Stand.J.PsychoL

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42 Neligan, G., and Prudham, D.: Potential value of four early

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43vm Riper, C.: Speech Cowection; Principles and Methods,

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three-year-old children. Pediatrics 48(2) :268-276, Aug. 1971.45 Martyn, M. M., Sheehan, J., and Slutz, K.: Incidence of

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=/6Dnllien, C. M., Jatneson, S., and Wilkinson, E. M.: Studiesin mental handicap. Part I: Prevalence and distribution by

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49Meyer, V., and Yates, A. J.: Intellectual changes foflowingtemporaf lobectomy for psychomotor epilepsy. J. NeuroL

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patients with psychomotor epilepsy. Epilepsia 4:80-90, Nov.1955.

5 lMilner, B.: Psychological defects produced by temporaflobe excision. Proc.Assn.Nerv.Ment.Dis. 36:244-257, 1958.

52Meyer, V.: Cognitive changes following temporal lobec-tomy for relief of temporaf lobe epilepsy. Arck.Neurol.81(3):299-309, Mar. 1959.

53 Blakemore, C. B., and Falconer, M. A.: Long-term effects

of anterior temporal lobectomy on certain cognitive functions.J.NeuroLNeurosurg.Psychirt. 30(4) :364-367, Aug. 1967.

5%4iiky, A. F., et al.: A comparison of the psychologicaltest performance of patients with focal and nonfocal epilepsy.Exp.NeuroL 2(1):75-89, Feb. 1960.

55Green, J, B., and Hartlage, L. C.: Comparative perform-ance of epileptic and nonepileptic children and adolescents.Dis.Nerv.Syst. 32(6):418-421, June 1971.

56 Campbell, M., and Reynolds, G.: The physical and mentaldevelopment of children with congenital heart disease. Arck.Dis.ChiU 24(120):294-302, Dec. 1949.

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Psychrizt. 77(1) :17-22, Jan. 1957.

58Linde, L. M., Rasof, B., and Dunn, O. J.: Mentaldevelopment in congenital heart disease. J.Pediatr.71(2): 198-203, Aug. 1967.

59 Feldt, R. H., et al.: Chddren with congenital heart disease.

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6%cHugh, G.: Changes in I.Q. at the pubfic schoolkindergarten level. PsychoLMonogr. 55(2):1-34, 1943.

61Wellman, B. L.: Some new bases for interpretation of theIQ. J. Gerset.PsychoL 41(1):116-126, Sept. 1932.

62Andemon, L. D.: A longitudinal study of the effects ofnursery-school training on successive intelligence-test ratings.39th Yearbook, NatlSoc. Study Educ. 11:3-10, 1940.

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64Bayley, N.: Factors influencing the growth of intelligence

in young children. 39th Yearbook NatLSoc. Study Educ. 11:49-79.1940.

65 Bird, G. E.: The effect of nursery-school attendance uponmentrd growth of children. 39th Yearbook Natl.Soc. StudyEduc. 11:81-84, 1940.

66 Frmdsen, A., ad Bmlow, F. p.: Influence of the n~se~

school on mental growth. 39th Yearbook NatlSoc. Study Educ.11:143-148.1940.

67Goodenougb, F. L., and Maurer, K. M.: The mentaldevelopment of nursery-school children compzred with that ofnon-nursery-school children 39th Yearbook Natl.Soc. StudyEduc. 11:161-178, 1940.

68Lamson, E. A.: A follow-up study of a group ofnursery-school children. 39th Yearbook NatLSoc. Study Educ.

11:231-236, 1940.

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Yearbook Natl.Soc. Study Educ. 11:237-244, 1940.

21

70Voas, W. H.: Does attendance at the Winnetka Nursery and effective development. Vol. I. Bladensburg, Maryland.School tend to raise the IQ? 39tlz Yearbook Natl.Soc. Study Westinghouse Learning Corp., June 1969.Educ. 11:363-376, 1940. 73National Center for Health Statistics: Sample design and

71Welbnan, B. L., and McCandless, B. R.: Factors associatedwith Binet IQ changes of preschool children. PsychoLMonogr.

estimation procedures for a national health examination survey

60(2):1-29, 1946. of children. Vital and Health Stati&s. Series 2-No. 43. DHEW

72Cicarelli, V., et al.: The impact of Head Start: An Pub. No. (HRA) 74-1005. Health Resources Administration.

evaluation of the effects of Head Start on chddren’s cognitive Washington. U.S. Government Printing Office, Aug. 1973.

22

LIST OF DETAILED TABLES

Table 1,

2,

3.

4,

5,

6.

7.

8.

9.

10.

11.

Mean deviation IQ and standard error of the mean on the short form of the Wechsler Intelligence Scale for

Children (WISC) and tha modified Goodenough-Harris Human Figure Drawing (HFD) tests for and numbar and

percent distribution of children 6-11 years of age, by educational attainment of mother and of father: United

Statas,1963-1965 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Mean deviation IQ and standard error of the mean on the short form of the Wechsler Intelligence Scale for

Children (WISC) and the modified Goodenough-Harris Human Figure Drawing (HFD) tasts for and number and

parcent distribution of children 6-11 years of age, by educational attainment of mother and of father: United

States, 1963-1965 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..,,

Mean deviation IQ and standard error of the mean on the short form of tha Wechsler Intelligence Scale for

Children (WISC) and the modified Goodenough-Harris Human Figure Drawing (HFD) tests for and percent

distribution ofchildren 6-11 years ofage, byplace of birth ofmother, aga, andsex: Unitad States, 1963-1965 . .

Mean daviation IQ and standard error of the mean on the short form of the Wechsler Intelligence Scale for

Children (WISC) and the modified Goodenough-Harris Human Figure Drawing (HFD) tests for and percent

distribution of children 6-11 years of aga, byageof mother andoffather atthetime of thechild's birth: United

States,1963-1965 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Mean deviation IQ and standard error of the mean on the short form of the Wechsler Intelligence Scale for

Children (WISC) and the modified Goodenough-Harris Human Figure Drawing (HFD) tests for and number and

percent distribution ofchildren 6-11 years of aW, bynumber ofchildren under 20years inthehousehold andwx

ofchild: UnitedStates, 1963-1965 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Mean deviation lQ and standard error of the mean on the WISC Vocabulary and Block Dasignand the modified

HFDtests for and percantof children 6-11 years ofage, byeducational attainment of first parent and numberof

children under 20years in the household: United States, 1963-1965 . . . . . . . . . . . . . . . . . . . . . . . . . .

Mean deviation lQ and standard error of the mean on tha short form of the Wechsler Intelligence %-ale for

Children (WISC) and the modified Goodenough-Harris Human Figure Drawing (HFD) tests for and parcent

distribution of chiidren 6-11 years of age, by numbarof deceased siblings (born dead orwhodied later) :United

States,1963-1965 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Mean deviation IQ and standard error of the mean on the short form of the Wechsler Intelligence Scale for

Childran (WISC) and the modified Goodanough-Harris Human Figure Drawing (HFD) tests for and number and

parcent distribution ofchildren 6-11 years, byageorder of thechild in the family: United States, 1963-1965 . .

Mean deviation lQ and standard error of the mean on the WISC Vocabulary and Block Design tests for children

6-11 years of age, by aga order of child in family and number of children under 20 years in the

household: UnitedStates, 1963-1965 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Mean deviation lQandstandard error of themean byageordar ofchild in family andeducation ofsecond parent

on the modified HFD test and by age order of child in family and education of first parant on the WISC

Vocabulary and Block Design tests: United States, 1963-1965 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Maan deviation IQ and standard error of the maan on the short form of the Wechsler Intelligence Scale for

Children (WISC)and themodified Goodenough-Harris Human Figure Drawing (H FD)tests forchildren 6-11 yaars

of age, by presance or absence of medical complications of mother during pragnancy and by education of the

second parentontheWISC: UnitedStates, 1963-1965 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Page

25

26

27

27

28

28

29

28

30

30

31

23

LIST OF DETAILED TABLES–Con.

Page

Table 12. Mean deviation IQ and standard error of the mean on the short form of the Wechsler intelligence Scale forChildren (WISC) and the modified Goodenough-Harris Human Figure Drawing (HFD) tests for and number andpercent distribution of childran 6-11 years of age, by birthweight, length of baby’s stay in hospital aftar birth,congenital malformations and birth injuries shown on birth certificate, handedness, and twin status: UnitedStatas,1963-1965 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

13, Mam deviation lQ and standard error of the mean on the short form of the Wechsler Intelligence Scale forchildren (WISC) and the modified Goodenough-Harris Human Figura Drawing (HFD) tests for and percentdistribution of children 6-11 years of age, by critical aspects of aarly developmental history: United States,1663-1965 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

14. Mean deviation lQ and standard error of the mean on the short form of the Wechsler Intalligenca Scala forChildren (WISC) and the modifiad Goodenough-Harris Human Figure Drawing (HFD)tests forand percent of

children 6-11 years of age, by findings of congenital and acquired chronic conditions on survey examination:UnitedStates, 1963-1965, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

1!5. Mean deviation lQ and standard arrorof the mean on the WISC Vocabulary and Block Design andthemodifiadHFD tasts for children 6-11 yaars of age, by race, kindergarten or nursery school experience, and educationalattainmantoffirstparent: UnitedStates, 1963-1965 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

24

Tablel. Mean deviation lQandstandard error of themean ontheshoR formoftha Wechsler intelligence Smlefor Children (WlSC)and the modified Goodenough-Harris Humeri Figure Drawing (HFD)tests forandnumber andpercent distribution ofchildren6-llyearn of age, by educational attainment of mother and of father: United States, 1963-1965

Education of father andof mother

Father (lst parent)

Lassthan5years . . . . . . . . . .6-Byears . . . . . . . . . . . . . . . .9-12years . . . . . . . . . . . . . . .13years or more . . . . . . . . . . .

Mother (2d parent)

Lessthan 5 years . . . . . . . . . .5-8years ..,.........,.. .9.12 years , . , . . . . . . . . . . . .13yaarsormore . . . . . . . . . . .

Father (lst parent)

Lessthan5years . . . . . . . . . .6-6years . . . . . . . . . . . . . . . .9.12 years . . . . . . . . . . . . . . .13years ormore . . . . . . . . . . .

Mother (2d parent~

Lessthan5years . . . . . . . . . .5-6years . . . . . . . . . . . . . . . .

9.12years . . . . . . . . . . . . . . .13yearsor more . . . ..m . . . . .

IWlsc I HFD

Combined VocabularyBlock ICombined

ManDesign Scale

86.193.9

100.2107.7

86.092.5

100.9108.3

0.860.760.300.52

1.300.720.320.85

83.893.6

101.0108.7

82.991.4

101.8110.3

Mean deviation IQ

68.595.4

100.6107.1

90.094.7

101.3107.7

90.496.8

100.0104.5

88.696.1

100.6103.7

Standard error of mean

1.520.830.490.58

2.100.98

L-0.430.77

0.510.750.310.71

0.920.580.431.08

91.097.9101.1105.0

91.097.4101.6104.1

L0.85 1.340.68 0.860.38 0.480.53 0.61

1.27 1.890.65 0.910.48 0.55 ~

0.60 0.72

WomanScale

92.597.6100.9105.8

90.397.0101.4105.1

1.540.540.410.61

1.770.860.510.61

Number ofchildren

in thousands

1,4194,116

10,I8?I4,256

8393,31413,0703,232

...---......

...

...-..---

Percentof

:hildren

7.120.651.021.3

4.116.263.915.8

...---...---

..----..-..-

25

Table2. Mean deviation lQandstandard error of thamean onthashoR form of the Wechsler lntelliWnce Smlefor Children (WISC) and the modified

Goodenough-Harris Human Figure Drawing (HFD) tests for and number and percent distribution of children 6-11 years of age, by aducetional

attainment of mother and of father: United States, 1963-1965

Education of father and

of mother

Father, under 5 years

Mother:

Under 5yaars . . . . . . .

5-8years . . . . . . . . . .

9-12 years . . . . . . . . .

13yearsorm0re . . . . .

Father, 5-8 years

Mother:

Under 5 years . . . . . . .

5-8years . . . . . . . . . .

9-12years . . . . . . . . .

13years0r more . . . . .

Father, 9-12 years

Mother:

Under 5 years . . . . . . .

5-8years . . . . . . . . . .

9-12 years . . . . . . . . .

13years or more . . . . .

Father, 13 yaars or more

Mother:

Under 5years . . . . . . .

5-8years . . . . . . . . . .

9-12 years . . . . . . . . .

13 years or more . . . . .

Wlsc ! HFD

II 1 11 I

Combined I Vocabulary I 810ck I ManCombined

Woman

Design Scale Scale

84.7

87.1

86.1

95.6

88.0

92.3

96.7

101.3

89.3

96.2

101.3

104.4

103.8

105.6

110.2

81.0

64.6

85.5

102.6

86.6

91.9

96.7

100.7

86.3

94.8

102.3

105.9

104.3

107.3

112.6

Mean deviation IQ

88.3

90.7

87.9

90.5

90.4

93.8

88.0

103.2

93.3

98.6

101,6

104.2

104.5

105.2

108.3

89.4

92.0

90.3

94.8

90.6

95.9

98.0

104.3

91.6

96.6

100.6

100.7

104.5

104.4

104.8

89.6

91.6

93.1

97.0

91.3

97.6

98.8

104.8

96.7

99.9

101.7

101.0

I 06.6

104.7

I 05.3

91.9

96.0

90.0

91.6

96.4

98.9

105.2

88.7

99.5

101.2

103.2

102.2

105.8

105.9

Standard error of mean

1.98

0.74

1.28

67.62

2.26

0.96

0.70

2.79

1.49

1.02

0.30

0.93

2.62

0.48

1.02

2.36

1.68

1.08

67.06

2.78

0.80

0.94

1.80

2.84

1.19

0.47

0.86

2.67

0.72

0.76

Number of

children

in thousands

502

846

284

7

193

1,531

2,250

140

132

978

8,223

856

94

2,124

2,039

‘arcent

of

hildren

35.4

45.5

18.6

0.5

4.7

37.2

54.7

3.4

1.39.6

80.7

6.4

2.2

49.9

47.9

26

7’ablo3, Mmndevimlm 10andstandard error .fthemeon onthe$horl form of the Wechs!er lntelfiSn- %lefor CMldren (WISC).nd lhemod,f,ed Gotien.ugh.Harrns Human F,o.re Drawtng (H FOltSef.r and

Percent dlstr#b.tno..f chi!dm.6.11 vearsof a9e. bvP!ace of blrthof mother..5e, a.dsex: Lf.tted S1ates,1963-1965

Wlsc HFD Perc,”t of

Percent of chaldre”

Combined Vwab”lmy 81.ck Dewm

chnldren vwth

Age and wCmnbm.!d Mm f!gure woman f,gure nmtherbom ,.

U.s.i Foreign t us.! Foreign S us., Foreign 1 U.S. I FOreIgnq us.,F.metg”

FO,e,gnl U.a.l Foreign: U.S., F.,.ign, us.country

Mean de.mtm. IQ

Total, 6.11 “Car, . . . . . . . . 99.6 91,9 1m,3 67.1 100.2 98.2 99.6 100.1 IL> 101.6 103.6 100.3 100.0 100.0 96.6 3.4

Gvcw$ . . . . . . . . . . . . . . . . 99.6 67,0 103.5 80.0 100.1 95.3 39.6 94.9 101.3 95.9 100.s 97.6?Vcim . . . . . . . . . . . . . .

17.3 26.3 ...

99.4 6S,4 103,3 S2.7 100.2 96.2 99.6 9s.1 10CI.5 101.3 100.9 97.38vccws . . . . . . . . . . . . . . .

17.299.9 94,1 103,6 66.6 100.2

16.1 .-.103.0 99.4 160.7 100.4 100.4 100.4 104.1

Llymrs . . . . . . . . . . . . . . . . . .

16.7

99.4

14,8 ... ..-

92,0 100,2 88,0 100.0 97,7 99,6 102.6 1CF3.3 106.1 100.6 100,0 16.7

Iovcars . . . . . . . . . . . . . . . . . .

17,2 -.. ..-

99.6 96,6 100.0 95.4 100,0 102.4 99,6 102.6 180.2 105.1 100.2 100.9 16.2

llwJr5 . . . . . . . . . . . . . . . . . .

17,9

99.6 98.9 103.3 106.0 100.4 93.6 100.1 102.6 103.5 101.7 100.7 102.6 15.9 5.7

B0vs,6.11 Years . 101.1 93.4 102.0 90.7 101.3 97.6 100.2 101.2 1CU2.4 102.0 93.2 90.4 50.9 39.5 . . -..

GMs,6.llymrs 98.2 90.9 98.5 64.7 99,0 96.5 99.0 96.S 101.4 100.3 102.1 102.7 49.1 60,5 . . .

Standard error of mm”

Totd,6.11 ”ems. ,, ..,., 0.55 2.06 0.74 2.06 0.47 2.23 0.55 1.99 0.63 1.93 0.50 2.56 . . -.. . .

Ovmrs 0.85 5,59 0.71 11.26 0.72 0,90 0.60 4.60 0.74 4.07 0.64 5,44 ... ..-

7Ye.3m . . . 0.64 6.43 0.79 6.36 0.64 4.59 0.72 2.34 0.93 3.98 0.67

8vrws . . . . . . . . . . . . . . .

230 . . . ..- .-.

0.51 7.82 0.76 6.47 0.43 13,12 0,63 2.99 0,91 2.41 0.72

Eivcws . 0.67

6.0S ..- .-. . . .

3,82 0,87 697 0.61 5.01 0,81 2.31 0.84 2,34 0.72 3.82 . . . . . . . .

Iowan. . . . . . . . . . . . . . . . . . 0,77 5,22 1,04 3.88 0.71 7.85 0.70 3.86 0,87 4.81 0.77 5.93 . .

ll”e3rs . . . . . . . . . . . . . . . . . . 0.81 5n.16 0.73 53.92 0,87 47s4 0.94 2.91 1.65 4.08 1.0s 4.45 . . . -..

60”s,6.11”,3,s . . . . . . . 0.63 2.7S 0.S3 3,33 0,53 3,43 0,63 1.23 0,63 1.11 0.82 3.65 . . . . . . . .

Glrlv6.llveara ... . . . . 0.53 3.25 0.69 4.15 0.50 2.49 0.58 3.26 0.93 6.S0 0.51 2.79 . . . . .

‘8k1hDla= of mother 12dmm. t).

Table4. Mean deviation lQandstindard error of themean ontheshoR form of the Wechsler intelligence Smlefor Children (WlSC)andthemodifiad Goodenough-Harris Human Figure Drawing (HFD) tests forand percent distribution of children 6-11 years of age,by age of mother and of father atthe time of thechild’s birth: United States, 1963-1965

Age of parent at birthof child

Mother

10-19 years . . . . . . . . . . .20-24 years....,...,..25.29 years . . . . . . . . . . .30-34 years..,..,..,..35-39 years ., .,,......40-44 year3 . . . . . . . . . . .45-54 years . . . . . . . . . . .

Ea$k

15-19 years . . . . . . . . . . .20.24 years . . . . . . . . . . .

25-29 years . . . . .. m....30.34 years . . . . . . . . . . .35-39 years . . . . . . . . . . .40-44 years . . . . . . . . . . .45-49 years . . . . . . . . . . .

60years And over . . . . . . .

Mean deviation IQ

94.999.0

101.0100,7101.197.890.3

96.2

98.4100.8101.099.8

100.095,5

92.3

95.099.4

101.6

101.9102.497.988.7

97.6

98.8101.3101.8101.1100.795.6

93.4

96.199.9

101.6100.7101.099.093.2

96.0

99.4101.5101.499.7

100.696.7

94.2

97.999.5

100.2100.4100.697.691.4

99.2

99.4100.4100.2100.699.096.8

94.8

98.3100.8100.7101.3101.798.596.3

100.3

100.7

101.1101.3101.0100.197.1

96.3

99.199.7

101.6101.7101.498.586.2

99.6

99.7101.4101.2102.2100.198.4

95.0

Wlsc HFDCombined Combined

Standard error of mean

0.500.650.600.730.921.644.20

0.79

0.540.630.740.740.961.33

1.90

0.500.550.640.580.961.244.30

0.86

0.560.430.650.771.081.51

3.00

Percentof

:hildren

11.030.827.319.09.22.50.2

2.5

20.628.323.114.06.72.4

1.4

27

Table 5. Mean deviation IQ and standard error of the mean on the short form of the Wechsler Intelli!fmce Scale for Children (WISC) and the modified Gocdenough. Harris HumanFigure Drawing (HFDI tests for and number and percent distribution of children 6-11 years of as, by numlxr of children under 20 years in the household and sex of child: UnltndStates, 1963-1965

IIIBothBoys Girls

sexes IIBothBOYS Girls

sexes

wlSCCo”bineti I HFDCombinedWlscNumber of children

under 20 yearsin household TGirls soysSoys Girls

PercentNumber in thousandsMean deviation IQ

99.6 100.6 99.s100.5 102.3 100.4101.5 101.9 103.199.7 100.s 100.559.3 100.0 100.698.0 99.5 9B.196.4 9B.B 98.193.6 93.7 96.2

Standard error of mean

0.78 0.8B 1.320.50 0.75 0.3B0.50 0.61 0.730.56 0.65 0.711.00 1.23 0.980.91 1.5B 0,91

1,21 1.46 1.731.08 1.52 1.32

5.31B.624.220.212.6

7.75.06.4

. . .

. . .

. . .

. . .

.-.

. . .

. . .

. . .

6.6

18.724.720.s12,2

7.64.75.9

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .—

103.9104.9102.s100.79B.696.693.4902

0.940.720.580.721.300.921.801.36

99.1101.0101.3

98.795.692.892.090.B

101.0101.9101.3100.1

99.s99.9B6.993.1

9s.099.0

101.s99.49B.896.095.984.2

1.240.5s0.760.720.911.02

1.731.36

1,2614,4255,7664,8042,9971,8311,1891,522

684!,259!,984!,513,474908568713

5972,1662,7722,2911,523

926621S09

6.118,623.919.613,0

7.95.26.8

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .—

1 child . . . . . . . . .Zchi[dren . . . . . . . . .3 children . . . . . . . . .4 children . . . . . . . . .5 children . . . . . . . . .6 children . . . . . . . . .7 children . . . . . . . . .B children or more . . .

101.6103.0102.1

99.B97.094.792.790.5

104.1

105.4103.4100.296.293.791.488.4

100.4101 .s102.1100.599.196.995.293.7

0.920.620.490.560.971.05

1.441,25

1.060.610.580.660.611.341.301.32

1.110.740.620.731.411.361.531.45

lchild . . . . . . . . . . .2 children . . . . . . . . .3 children . . . . . . . . .4 children . . . . . . . . .5 children . . . . . . . . .6 children . . . . . . . . .7 children . . . . . . . . .8 children or more . . .

0.820.%0.430.590.920.96

1.271.12

0.940.740.550.750.961.08

1.391.24

...

. ..

. ..

.. .

. . .

...

. ..

...

. ..

...

...

. ..

. ..

...

...

...

. ..

. ..

. ..

...

...

. ..

...

Table 6. Mean deviation IQ and standard error of the mean on the WISC Vocabulary and Block Design and the modified HFD tests for and percent of children S-11 years of age, byeducational attainment of first parent and number of children under 20 years in the household: United States, 1963-1965

II5-8 9-12 13 yearsyears years or moro

Education of first parent

I 1 ILessthan 5 years I 5-8 years I 9-12 years I 13 years or m m

HFD

103.6104.1105.3105.0

105,1

102.6105.397.5

Number of childrenunder 20 yearsin household

Lessthan5 years

4.77.49.4

15.7

19,2

12.211.719.7

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

F Wlsc

HFDVocab. BlockuIafy Design E Wlsc

HFDVocab- Blockulary Design

WLSCWlsc

HFDVocab-

ularyBlockDesign

Vocab-

ulary

BlockDesign

Mean deviation IQ

99.4 106.0 100.7

96.7 104.s 101.199.9 102.B 101.s96.2 100.7 100.696,2 97.6 100.8

96.8 94.9 98.435.3 95.2 98.234.5 92.6 96.7

100.095.B97.494.491.8

90.887.787.o

99.396.296.695.6

95.093.493.392.6

99.B 110.2100.3 113.3100.7 110.5100.0 108.8100.9 105.6

98.7 104.497.9 105.897.9 101.7

106.2107.3107.5108.2

105.7106,3104.0102.9

6.414.719.218.7

13.710,28.o9.1

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

1 child . . . . . . . . . . .2 children . . . . . . . . .3 children . . . . . . . . .4 children . . . . . . . . .5 children . . . . . . . . .6 children . . . . . . . . .7 children . . . . . . . . .B children or more . . .

94.0S9.5B5.488.3

83.083.0S1 .679.1

6.603.842.lB1.46

2.24

2.603.W2.60

90.292.391.290.789.589.5S7.787.4

1.772,631.36O.B1

1.41

1.Oa1.431.20

S9.592.893.5

90.393,030.135.9

Standard error of mean

1 child . . . . . . . . . . .2 children . . . . . . . . .3 children . . . . . . . . .4 children . . . . . . . . .5 children . . . . . . . . .

6 children . . . . . . . . .7 children . . . . . . . . .S children or more . . .

1.661.001.201.17

1.41

1.741.271.50

0.960.540.710.510.84

1.111.s31.50

1.010.650.750.74

0.92

1.351.551.40

2.590.B50.701.11

1.14

2.852.712.BO

2.S51.150.711.28

2,78

2.944.573.70

1.970.650.920.84

1.77

2.165.623.80 L................................................

4.192.442.151.44

2.19

1.552.542.00 L

0.97 1.291.17 0.710.96 1.OB1.10 1.oB

1.36 1.34

1.29 1.231.69 1.441.50 1.30

0.800.550.610.68

0.77

1.291.751.50

28

Tabla 7. Mean deviation IQ and standard error of the mean on the short form of the Wechsler Intelligence Scale for Children (w[SC)and the modified Goodenouqh-Harris Human Figure Drawing (H FD) tests for and percent distribution of children 6-11 years ofage, by number of deceasad si~lings (born dead or-who died later): United States, 1963-1965

Number of decaasedsiblings

Wlsc

HFD

99.798.698.199.088.492.6

99.996.6

93.983.390.998.2

Wlsc

HFD‘ercent

of

:hildrenCombined VocabularyBlockDesign

Born dead

None, ,, . . . . . . . . . . . . .I sibling . . . . . . . . . . . . . .2siblings . . . . . . . . . . . . .3siblings . . . . . . . . . . . . .4siblings . . . . . . . . . . . . .5siblingsormore .,, . . . .

Liveborn but diedbefore surtq

None . . . . . . . . . . . . . . . .I sibling . . . . . . . . . . . . . .

2siblings . . . . . . . . . . . . .3siblings . . . . . . . . . . . . .4siblings . . . . . . . . . . . . .5siblingsormore . . . . . . .

Mean deviationlQ Standard error of mean

99.697.399.497.886.296.6

88.995.2

91,784.892.187.6

100.298.098.297,586.695.6

100.595.5

91,881.894.587.6

100.197.7

101.998.987.498.3

100.496.0

92.788.090.88S.6

0.600.742.99

●

**

0.580.821.823.49

●

*

0.800.962.50

***

0.771.193.005.75

**

0.500.773.68

**●

0.500.740.882.28

●

*

0.600.722.90

*●

*

0.511.04

1.796.21

●

●

93.94.41.10.30.20.1

92.65.8

1.10.30.10.1

Table8. Mean deviation IQ and standard srror of the mean on the short form of the Wechsler Intelligence Scale for Children (WISC) and the modified

Gcmdenough-Harris Human Figure Drawing (HFD) tests for and number andpercent distributicm of children 6-11 years, by age order of the child in the

family: United States, 1963-1965

Wlsc I HFD WISCCombined I HFDCOmbinedNumber Of

children

in thousands

6,S97

6,969

5,114

2,664

1,142

999

. . .

. . .

. . .

-..

. . .

.-.

Percent

ofAge order of

child in family Vocab- Block Man Woman:ombi ned Combined

ulary Design Scale ScaleBoys Girls Boys Girls

Mean deviaticm IQ

First, . . . . . . . . . .

Sasond . . . . . . . . .

Third . . . . . . . . . . .

Fourth . . . . . . . . . .

Fifth . . . . . . . . . . .

Sixth orlater . . . . .

101.2 102.9

100.5 101.5

99.4 99,3

96.5 96.1

93.8 92.3

92.1 91.3

100.8

100.8

100.7

98.1

88.5

94.1

0.53

0.45

0.62

0.92

1.18

1.00

100.3

100.2

99.8

97.9

96.7

96.2

101.4

101.3

100.6

9B.9

96.8

96.0

100.8

100.8

100.9

99.3

98.6

99.4

99.3

89.1

98.5

95.7

93.7

92.1

101.2

100.8

100.2

9S.2

96.1

96.4

99.3

99.5

99.5

97.6

97.2

96.0

29.0

29.3

21.5

11.2

4.8

4.2

. . .

. . .

. . .

. . .

.-.

---

103.0

101.9

100.3

97.3

93.8

92.1

0.71

0.61

0.87

1.22

1.71

1.20

Standarderrorof mean

1

0.46 0.65 0.57

0.56 0.72 0.47

0.58 0.73 0.71

0.98 1.36 0.70

1.23 1.84 1.30

1.50 1.60 1.80

First, . ...,.,...

Second . . . . . . . . .

Third, . . . . . . . . . .

Fourth, . . . . . . . . .

Fifth . . . . . . . . . . .

Sixth or later . . . . . J-0.60 0.78

0.52 0.71

0.62 0.77

0.87 1.07

1.28 1.46

1.10 1.50 _l---.L0.64 0.62 0.61

0.57 0.73 0.56

0.60 0.81 0.74

0.81 1.35 0.86

1.19 1.90 1.48

1.20 1.70 1.60

29

Table9. Mean deviation lQ and standard error of themean onthe WISCVaabulaW and Block Design tests forchildren6-ll years ofage, by age

order ofchild in family andnumber ofchildren under 20years in the household: United States, 1963-1966

WISC Vocabulary WISC Block Design

Number of persons under 20 years in household Number of persons under 20 years in householdAge order of childin family

=

100.6 92.5

97.6 94.5100.2 97.9

98.4 95.698.8 95.7

- 94.1

2.07 1.61

0.97 1.40

1.23 1.66

1.23 0.96

2.48 1.19. . . 1.01

IEEE ZEc3 4 21 12

Mean deviation IQ

98.1

95.5

95.896.395.6

89.4

90.192.5

91.591.2

91.3

100.4104.1 106.0

104.9

103.9

103.3103.1

99.1

100.4100.3100.9

0.96

0.96

0.930.99

102.0

101.7

101.6

102.3

102.2

0.98

0.57

0.68---. . ..-.

99.8

101.0100.6100.6

1.06

0.86

0.841.15

. . .

. . .

First.............Second . . . . . . . . . . . .Third . . . . . . . . . . . . .Fourth . . . . . . . . . . . .

Fifth . . . . . . . . . . . . .

Sixth orlater . . . . . . . .

Standard error of mean

w

First . . . . . . . . . . . . .

Second . . . . . . . . . . . .

Third . . . . . . . . . . . . .Fourth . . . . . . . . . . . .

Fifth . . . . . . . . . . . . .Sixth orlater . . . . . . . .

0.94 0.97

0.73

0.70

0.75

0.80

Table 10. Mean deviation lQandstandard error of themean byageorder ofchild in family andeducation ofsecond parent onthemodified HFDtest and by age order of child in family and education of first parent on the WISC Vocabulary and 810ck Design tests: United Stetes,

1963-1965

WISC Vocabulary WISC Block Design

Education of first parent Education of first parant

HFD

Education of second parentAge order ofchild in family

13 yearsor more

103.5103.2

104.1

105.5

106.995.6

Under

5 years

88.284.4

84.0

81.6

81.981.7

Mean deviation IQ

95.5 102.894.0 101.6

84.1 100.3

90.6 99.191.7 96.192.2 94.2

96.6 100.6 106.694.7 101.2 107.196.9 100.6 108.6

93.2 100.4 106.395.5 99.0 107.692.6 97.6 98.0

First . . . . . . . . . . .Second . . . . . . . . .

Third . . . . . . . . . .

Fourth . . . . . . . . .

Fifth . . . . . . . . . .Sixthorlater . . . . .

95.289.1

89.0

88.1

86.690.9

95.697.8

95.5

95.0

95.599.5

111.5 91.0110.7 90.0107.8 89.7

106.8 88.1103.2 88.799.8 88.9

100.8100.6101.0

99.0

99.698.3

0.430.67

0.59

1.110.96

2.90

Standard error of mean

First . . . . . . . . . . .Second . . . . . . . . .Third . . . . . . . . . .

Fourth . . . . . . . . .

Fifth . . . . . . . . . .Sixth or later . . . . . L

1.62 0.941.93 1.202.12 0.92

3.48 1.163.53 2.085.54 3.18

0.960.53

1.11

1.53

3.85

5.95 I1.64 0.99 0.662.31 0.97 0.49

2.15 1.09 0.60

2.82 0.85 0.701.59 1.63 1.082.07 1.35 1.90

0.780.67

0.70

0.82

1.85

22.84

1.110.90

1.41

0.89

1.252.42

0.841.00

1.04

1.06

1.651.42

0.450.43

0.48

0.87

1.101.61

1.100.86

1.06

1.673.32

22.08

30

Table Il. Mean deviation lQands@ndard error oftiemean ontheshoti form of the Wechsler intelligence Smlefor Children (WlSC)and the modified Goodenough-Harris Human Figure “Drawing (HFD) tests forchildren 6-11 years of age, bypresence orabsenceofmedical complications of motharduring pregnancy and byedumtion of thesecond parent onthe WlSC: United Statas,1963-1965

Item

Combinad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .’ . . . . . . . . . . . . . .Vocabulary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Block Design . . .,, .,.,. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Combinad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Man Scale . . . . . . . . . ...’... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Woman Scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

WISC Combined

Education of second parant:Less than 5yaars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-8years ..,........,.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9.12years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

13yaars ormore . . . .. o..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Medical complications of mother during pragnancy

Some None

Mean deviation IQ

100.1101.6100.0

99.6100.8100.6

92.192.4

100.6108.0

99.9100.6100.4

99.6100.5100.5

85.292.5

101.0108.3

Some I None

Standard error of mean

0.861.080.99

0.641.080.70

3.721.440.711.38

0.650.860.63

0.480.590.42

1.400.720.310.82

31

Table 12. Mean deviation lQandstandard error of the mean ontheshort form of the Wechsler intelligence Smlefor Children (WISC)and themodified

Goodenough-Harris Human Figure Drawing (HFD) tests for and number and parcent distribution of children 6-11 years of age, by birthweight, Iangth of

baby ’s stay in hospital after bir’th, congenital malformations and birth injuries shown on birth certificate, handedness, and twin status: Unitad Statas,

1963-1965

Item

Birthwaight

Undar5 pounds . . . . . . . .

5-10 pounds . . . . . . . . . .

More than 10 pounds . . . .

Langth of baby’s stay

in hospital after birth

Undarl week . . . . . . . . .

l-2waaks . . . . . . . . . . . .

0var2waeks . . . . . . . . . .

Congenital malformation

Condition recorded on birth

certificetq . . . . . . . . . .

None recorded . . . . . . . . .

Birth injury

Condition recorded on

birth certificate . . . . . .

Nona recorded . . . . . . . . .

Handedness

Right . . . . . . . . . . . . . . .

Left . . . . . . . . . . . . . . . .

Ambidextrous . . . . . . . . .

Twin status

Notatwin . . . . . . . . . . .

Identiceltwin . . . . . . . . .

Fratarnaltwin . . . . . . . . .

Twin, type unknown . . . .

94.6

99.6

95.6

100.4101.795.8

97.6100.1

93.199.6

99.0

99.190.6

99.498.496,086.1

HFD

==ll=E=

95.5100.2

95.3

101.2102.996.7

97.6100.8

91.4100.4

99.6100.3

88.6

100.09B.O96.485.6

Mean deviation IQ

95.010Q.297.1

100,9101.996.2

98.6100.6

95.8100.1

99.788.292.4

100.0100.2

96,887.8

96.089.798.0

100.3100.596.0

100.099.7

99.488.1

88.688.292.5

88.696.897.486.6

96.3100.597.4

101.2100.698.0

100.9

107.099.9

100.499.997.1

100.692.695.784.1

97.5100.997.7

101.3102.098.0

99.6100.9

96.1100.3

100.4100.0

75.0

100.5100.9100.7

91.2

IWlsc HFD

Combined Combined

Standard error of maan

0.660.631.61

0.440.990.72

2.080.52

5.900.68

0.670.62

21.96

0.612.361.65

4.06

1.280.681.43

0.410.981.27

3.060.88

3.960.80

0.530.55

22.97

0.602.332.76

2.58

Numberof

children

in thousands

690

22,785

308

21,210

1,780

7~4

238

23,646

71

23,713

21,215

2,545

24

23,332

143

285

24

‘arcent

of

;hiidran

2.995.8

1.3

88.87.43,0

1.099.0

0.399.7

89,210,70.1

98.10.61.20.1

32

Table 13. Mean deviation lQ and standard error of the mean ontheshort formof the Wechsler Intelligence Scale for Children (WISC) and themcdified Goodenouirh-Harris Human I%ure Drawinq (HFD)tesS forandwrcent distribution ofchildwn6-ll Years of a9e. bv critical asPects of early developmental history: United States,

1963-1965 -

Early developmental

history

Acceptance of changefrom breast feeding

No problem ., ..,,,.

Someproblem . . . . . . .Considerable problem . .

Age child first walked

Under 12 months ., . . .

12-18 months . . . , . . .0ver18 months . . . . . . .

Don’t know . . . . . . . . .

Age child first spoke

Under 12 months . . . . .

12-18 months . . . . . . .

0vw18 months . . . . . . .Don$t know . . . . . . . .

Problems with talking

Some . . . . . . . . . . . . . .

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

Don’t know .,.,.....

Learning speed

Faster . . . . . . . . . . . . .

Average . . . . . . . . . . . .

Slower . . . . . . . . . . . . .

Don’t know . . . . . . . . .

Health at 1 year

Good, . . . . . . . . . . . . .

Fair . . . . . . . . . . . . . . .

Poor . . . . . . . . . . . . . .

80YS and girls

Combined

F

Mean deviation IQ

100.2

96.696.2

1Oo.c

99,689.9

94.6

101.099.2

94.496.9

85.0

99.8●

102.8

99.0

89.2

95.4

99.7

97.0

92.7

100.6

98.598.9

100.3

88.680.6

94.0

101.199.2

94.6

98.1

96.0

99.9.

102.1

99.4

90.6

98.4

88.9

97.8

92.7

Combined

T

Standard error

0.83

1.472.33

0.66

0.56

1.191.67

0.590.59

1.190.67

0.86

0.60.

0.88

0.61

1.23

1.83

0.63

0.74

1.06

0.76

1.623.10

0.61

0.471.371.48

0.640.57

1.20

0.80

0.86

0.49.

0.75

0.46

1.49

2.08

0.51

0.76

2.15

Mean deviation IQ

101.8

97,0100.7

fol.5

100.990.3

93.5

102.6100.7

96.3

98.2

96.6

101.1.

105.6

100.4

90.2

93.8

101.0

98.9

95.2

101.5

98.0101.6

101.4

98.9

90.893.3

101.9100.0

95.7

97.9

86.5

10Q.6.

103.9

99.9

92.2

98.4

100.4

89.0

93.1

98.6

96.4

96.1

98.5

98.2

89.485.5

99.597.4

81.6

97.6

92.7

98.4.

100.8

97.5

87.2

97.4

98.4

94.6

80.1

89.7

98.9

86.6

99.2

99.4

80.494.6

100.4

98.493.0

88.3

95.2

89.2.

100.8

98.8

87.4

98.5

88.3

96.3

92.2

100.6

98.1

101.0

100.8

100.2

88.494.8

102.099.6

94.1

97.0

93.8

100.5●

104.4

89.5

87.0

94.8

100.4

97.1

92.3

101.1

96.4

96.6

100.4100.3

92.495.5

101.1100.0

95.9

98.0

97.5

100.2.

102.8

99.7

92.4

97.0

100.3

88.1

94.1

101.9

97.8

99.2

101.8100.2

90.884.1

102.1

100.3

85.8

99.0

96.3

100.9.

103.8

100.3

92.1

97.5

1CO.8

8S.5

94.8

101.2

103.41Cm.3

100.8101.0

92.396.2

102.189.9

84.8

99.0

97.0

1CCI.8.

103.0

10+3.2

89.1

103.2

1M.9

97.8

92.7

-

‘ercent

of

90.5

7.9

1s

47.747.3

3.61.4

42.8

41.18.5

7.6

8.4

91.6.

20.2

74.9

4.2

0.7

90.87.6

1.7

33

Table 14. Mean deviation IQ and standarderror of the mean cm the short form of the Wechsler Intelligence Scale for Children (WISCI and the modified Goodenough.

Harris Human Figure Drawing (HFD) tests for and percent of children 6-11 years of age, by findines of congenital and acquired chronic conditions on survey examlna.

tion: United States, 1963-1965

Boys Girls

Combined Combined Boys and girls

~

%rcent

ofhildren

0.30.1

1.9

0.7

97.4

96.4

1.9

1.7

0.5

0.3

0.6

2.2

Boys and girls

Combined

=1=

Combined

T

Item

Wlsc HFD Wlsc HFDVocab. Block Man Woman

ulary Design scale scale

Medical history of Mean deviation IQ Standard error Mean deviation IQ

2.79

3.20

2.23

2.60

0.62

0.621.32

2.!M

2.31

4.35

2.99

1.61

3.93

6.63

1.641.59

0.52

0.521.70

2.27

. . .

.-.

. . .

. . .

91.8

80.0

92.4

89.7

98.4

98.491.4

98.1

81.8

73.6

94.2

98.4

86.7

72.2

95.5

95.8

99.2

99.286.3

95.3

. . .

-..

. . .

.-.

93.4

83.2

93.6

96.9

100.4

100.4

93.5

98.5

90.1

67.2

96.9

100.5

94.7 I

83.6

94.7

96.7

99.7

99.794.1

96.1

69.9

76.8

96.9

99.2

91.978.7

95.1

97.1

99.9

99.991.6

94.8

.-.

. . .

. . .

-..

Epilepsy . . . . . . . . . . . .

Cerebral palsy . . . . . . . .

98.887.2

96.5

102.2

101.1

101.196.4

94.6

92.0

79.2

100.6

99.7

96.4

65.2

94.8

98.1

100.6

100.694.5

94.4

.-.

. . .

. . .

. . .

97.284.6

97.0

97.8

100.3

100.395.9

96.8

80.9

87.3

98.4

99.1

93.861.8

95.5

98.5

100.9

100.896.0

94.3

. . .

. . .

. . .

-..

92,1

77.2

96.5

96,6

100.9

100.988.4

97.4

. . .

. . .

. . .

. . .

Present health findings

on examination

Heart condition:

Congenital . . . . . . . .

Acquired . . . . . . . . .

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

Neurological.musc ulo-

skeletal condition:

None . . . . . . . . .Congenital . . . . . .

Acquired . . . . . . .

Cerebral palsy, other

cerebral problems or

minimal cerebral

dysfunction . . . . . . .

Mongolism or mentalretardation . . . . . . . .

Eye disorderc . . . . . . . .

Musculoskeletal jointdisorders only . . . . . .

Table 15. Mean deviation lQandstandard error of themean onthe WISCVocabularv and Block Desiqnand themdified HFDtests forchildren6-ll

years ofage, byrace, kindergarten ornursery school experience, andeducational attainment of;irat parenti United Statas,1963-1965

Child attended kindergarten or nursery school Child did not attend kindergarten or nursery school

WISC Vocabulary WISC Block Design HFD WISC Vocabulary WISC Block Design HFDEducation of first

parent I t 1 I ,

White Negro White Negro White Negro Whita Negro White Negro White Negro

Mean deviation IQ

All children . . . . . . 104.3 I 90.1 103.4 I 91.6 101.7 96.9I

96.3I

65.0 I 97.4 88.1

~

97.5 91.0I

Lessthan 6years . . . . . . .5-8years . . . . . . . . . . . .9-12yaars . . . . . . . . . . . .13yeara0rm0re . . . . . . .

87.3 84.199.0 87.2

103.0 91.6110.6 99.1

92.3 88.699.1 90.4

102.4 92.3108.2 95.6

91.596.399.0

102.2

85.492.293.397.8

Standard error of mean

0.70 1.08 0.54 0.27 0.54 0.74 1.53 2.28 0.77 0.96 0.88 1.20

2.69 2.s4 1.67 1.32 2.78 1.45 2.26 1.65 0.570.83

0.87 1.04 1.641.05 0.s4 0.38 1.08 1.68 0.87 3.02 1.02 0.94 1.05 1.59

0.55 1.17 0.44 0.54 0.50 0.71 0.90 2.26 0.48 0.89 0.79 1,770.70 2.08 0.78 2.38 0.57 2.46 1.03 7.66 1.02 2.66 1.10 4.98

All children . . . . . .

Less than 6 years . . . . . . .

5-S years . . . . . . . . . . . .

9-12 years . . . . . . . . . . . .

13years ormore . . . . . . .

_ -—-——

34

.

APPENDIX I

STATISTICAL NOTES

The Survey Design

The sample design for the second cycle of theHealth Examination Survey, similar to the oneused for the first cycle, was that of a multistage,stratified probability sample of loose clusters ofpersons in land-based segments. Successive ele-ments dealt with in the process of sampling areprimary sampling unit (PSU), census enumera-tion district (ED), segment, household, eligiblechild (EC), and finally, the sample child (SC).

At the first stage, the nearly 2,000 PSU’S intowhich the United States (including Hawaii andAlaska) has been divided and then grouped into357 strata for use in the Current PopulationSurvey and the Health Interview Survey werefurther grouped into 40 superstrata for use inCycle II of the Health Examination Survey. Theaverage size of each Cycle II stratum was 4.5million persons, and all fell between the limits of3.5 and 5.5 million. Grouping into 40 strata wasdone in a way that maximized homogeneity ofthe PSU’S included in each stratum, particularlywith regard to degree of urbanization, geo-graphic proximity, and degree of industriali-zation. The 40 strata were classified into fourbroad geographic regions (each with 10 strata)of approximately equal population and crossclassified into four broad population densitygroups (each having 10 strata). Each of the 16cells contained either two or three strata. Asingle stratum might include only one PSU (oronly part of a PSU as, for example, New YorkCity, which represented two strata) or severalscore PSU’S.

To take account of the possible effect thatthe rate of population change between the 1950and 1960 census might have had on health, the10 strata within each region were further classi-

fied into four classes, ranging from those withno increase to those with the greatest relativeincrease. Each such class contained either two orthree strata.

One PSU was “then selected from each of the40 strata. A controlled selection technique wwused in which the probability y of selection of aparticular PSU was proportional to its 1960population. In the controlled selection an at-tempt was also made to maximize the spread ofthe PSU’S among the States. While not every oneof the 64 cells in the 4 X 4 X 4 grid contributesa PSU to the sample of 40 PSU’S, the controlledselection technique ensured the sample’s match-ing the marginal distributions in all three dimen-sions and being closely representative of all crossclassifications.

Generally, 20 ED’s were selected within aparticular PSU. The probability of selection of aparticular ED was proportional to its populationin the age group 5-9 years in the 1960 census,which by 1963 roughly approximated the popu-lation in the target age group for Cycle II. Asimilar method was used for selecting onesegment (cluster of households) in each ED.Each of the resultant 20 segments was either abounded area or a cluster of households (oraddresses). All children in the age range 6-11years normally resident at each household oraddress were considered EC’S. Operational con-siderations made it necessary to reduce thenumber of prospective examinees at any onelocation to a maximum of 200. The EC’s to beexcluded for this reason from the SC group weredetermined by systematic subsampling.

The total sample thus selected for the exami-nation included 7,417 children (SC’s) from 25different States in the age group 6-11 years, withapproximately 1,000 at each of the single yearsof age.

35

Reliability

Measurement and assessment processes em-ployed in the survey were highly standardizedand closely controlled. Of course this does notmean that the correspondence between the realworld and the survey results is exact. Data fromthe survey are imperfect for three major reasons:(1) results are subject to sampling error, (2) theactual conduct of a survey never agrees perfectlywith the design, and (3) the measurement orassessment processes themselves are inexact eventhough standardized and controlled.

The first report on Cycle 114 describes indetail the faithfulness with which the samplingdesign was carried out. It notes that 7,119 outof the 7,417 sample children were examined.This is a response rate of 96 percent. Theexamined children were a highly representativesample of children of this age in the noninsti-tutional population of the United States. Theresponse levels for the various demographicsubgroups-including those for age, sex, race,region, population density, parent’s educationallevel, and family income–show no markeddifferentials. Hence it appears unlikely thatnonresponse could have biased the findingsmarkedly in these respects. Further descriptionof the sample design and estimation proceduresis contained in a subsequent report.73

The general measures used to control thequality of data from this survey have been citedpreviously.4 as have those relating specifically tothe psychological test measures.6 $9

Data recorded for each sample child areinflated in the estimation process to characterizethe larger universe of which the sample child isrepresentative. The weights used in this inflationprocess are a product of the reciprocal of theprobability of selecting the child, an adjustmentfor nonresponse cases, and a poststratified ratioadjustment that increases precision by bringingsurvey results into closer alinement with knownU.S. population figures by color and sex forsingle years of age 6 through 11.

In the second cycle of the Health Examina-tion Survey, the sample was the result of threestages of selection—the single PSU from eachstratum, the 20 segments from each sample PSU,and the SC’s from the EC’S. The probability ofselecting an individual child is the product of theprobability of selection at each stage.

Since the strata are roughly equal in popula-tion size and a nearly equal number of samplechildren were examined in each sample PSU, thesample design is essentially self-weighting withrespect to the target population; that is, eachchild 6 through ,11 years had about the sameprobability of being drawn into the sample.

The adjustment upward for nonresponse isintended to minimize the impact of nonresponseon final estimates by imputing to nonrespon’d-ents the characteristics of “similar” respondents.Here similar respondents were judged to beexamined children in a sample PSU having thesame age in years and sex as children notexamined in that sample PSU.

The poststratified ratio adjustment used inthe second cycle achieved most of the gains inprecision that would have been attained if thesample had been drawn from a populationstratified by age, color, and sex and made thefinal sample estimates of population agree ex-actly with independent controls prepared by theBureau of the Census for the noninstitutionalU.S. population as of August 1, 1964 (approx-imate midsurvey point), by color and sex foreach single year of age 6 through 11. The weightof every responding sample child in each of the24 age, color, and sex classes is adjusted upwardor downward so that the weighted total withinthe class equals the indepe~dentcontrol.

Sampling and Measurement Error

population

In the present report, reference has beenmade to efforts to minimize bias and variabilityof measurement techniques.

The probability design of the survey makespossible the calculation of sampling errors. Thesampling error is used here to determine howimprecise the survey test results may be becausethey come from a sample rather than from themeasurements of all elements in the universe.

The estimation of sampling errors for a studyof the type of the Health Examination Survey isdifficult for at least three reasons: (1) Measure-ment error and “pure” sampling error areconfounded in the data—it is not easy to find aprocedure which will either completely includeboth or treat one or the other separately, (2) thesurvey design and estimation procedure are

36

complex and accordinglytionallv involved techniques

require computa-for the calculation.

of variances, and (3) thousands of statisticscome from the survey, many for subclasses ofthe population for which there are few cases.Estimates of sampling error are obtained fromthe sample data and are themselves subject tosampling e~or, which may be large when thenumber of cases in a cell is small or occasionallyeven when the number of cases is substantial.

Estimates of approximate sampling variabilityfor selected statistics used in this report arepresented in the detailed tables. These estimateshave been prepared by a replication techniquethat yields overall variabilityy through observa-tion of variability among random subsamples ofthe total sample. The method reflects both“pure” sampling variance and a part of themeasurement variance.

In accordance with usual practice, the intervalestimate for any statistic may be considered therange within one standard error of the tabulatedstatistic, with 68-percent confidence, or therange within two standard errors of the tabu-

lated statistic, with 95-percent confidence. Thelatter is used as the level of significance in this ,report.

An approximation of the standard error of adifference d = x - y of two statistics x and y isgiven by the formula

where S% and SY are the sampling errors,respectively, of x and y.

Small Categories

In some tables magnitudes are shown for cellsfor which the sample size is so small that thesampling error may be several times as great asthe statistic itself. Obviously in such instancesthe statistic has no meaning in itself except toindicate that the true quantity is small. Suchnumbers, if shown, have been included in thebelief that they may help to convey an impres-sion of the overall story of the table.

37

APPENDIX II

DEMOGRAPHIC AND SOCIOECONOMIC TERMS

Age.–The age recorded for each child was theage at last birthday on the date of examination.The age criterion for inclusion in the sampleused in this survey was defined in terms of age attime of interview. Since the examination usuallytook place 2 to 4 weeks after the interview,some of those who w,ere 11 years old at the timeof interview became 12 years old by the time ofexamination. There were 7.2 such cases. In theadjustment and weighting procedures used toproduce national estimates, these 72 were in-cluded in the 1l-year-old group.

Race.–The age order of the child is theirrelative ranking by date of birth. Race wasrecorded as “white,” “Negro,” or “other.$’“Other” included American Indians, Chinese,Japanese, and all races other than white orNegro. Mexican persons were included with“white” unless definitely known to be AmericanIndian or of another race. Negroes and personsof mixed Negro and other parentage wererecorded as “Negro.”

Geographic re&”on,–For purposes of stratifi-cation the United States was divided into fourgeographic regions of approximately equal popu-lation. These regions, which correspond closelyto those used by the U.S. Bureau of the Census,were as follows:-

Region

Northeast . . .

Midwest . . . .

South . . . . . .

States included

Maine, Vermont, New Hamp-shire, Massachusetts, Connecti-cut, Rhode Island, New York,New Jersey, and PennsylvaniaOhio, Illinois, Indiana, Michi-gan, Wisconsin, +Minnesota,Iowa, and MissouriDelaware, Maryland, Districtof Columbia, West Virginia,Virginia, Kentucky, Tenn-

West . . . . . . .

essee, North Carolina, SouthCarolina, Georgia, Florida,Alabama, Mississippi, Louisi-ana, and ArkansasWas hington, Oregon, Cali-fornia, Nevada, Ne-w Mexico,Arizona, Texas, Oklahoma,Kansas, Nebraska, NorthDakota, South Dakota, Idaho,Utah, Colorado, Montana,Wyoming, Alaska, and Hawaii

Urban and rural. –The definition of urban andrural areas was the same as that used in the 1960census. According to this definition, the urbanpopulation was comprised of all persons living in(a) places of 2,500 inhabitants or more incor-porated as cities, boroughs, villages, and towns(except towns in New England, New York, andWisconsin); (b) the densely settled urban fringe,whether incorporated or unincorporated, ofurbanized areas; (c) towns in New England andtownships in New Jersey and Pennsylvania thatcontained no incorporated municipalities as sub-divisions and had either 2,500 inhabitants ormore, or a population of 2,500 to 25,000 and adensity of 1,500 persons or more per squaremile; (d) counties in States other than the NewEngland States, New Jersey, and Pennsylvaniathat had no incorporated municipalities withintheir boundaries and had a density of 1,500persons or more per square mile; and (e)unincorporated places of 2,500 inhabitants ormore not included in any urban fringe. Theremaining population was classified as rural.

Urban areas are further classified by popu-lation size for places within urbanized areas andother urban places outside urbanized areas.

Family income. –The income recorded wasthe total income of the past 12 months receivedby the head of the household and all other

38

household members related to the head byblood, marriage, or adoption. This income wasthe gross cash income (excluding pay in kind)except in the case of a family with their ownfarm or business, in which case net income wasrecorded.

Parent. –A parent was the natural parent or,in the case of adoption, the legal parent of thechild. When both parents were present in thehousehold, the mother is referred to here as thesecond parent.

Guardian. –A guardian was the person re-sponsible for the care and supervision of thechild. He (or she) did not have to be the legalguardian to be considered the guardian for thissurvey. A guardianship could od”y exist whenthe parent(s) of the child did not reside withinthe sample household.

Head of household. –Only one person in eachhousehold was designated as the “head.” He (or

she) was the person who was regarded as the“head” by the members of the household. Inmost cases, the head was the chief breadwinnerof the family, although this was not always true.In this report the head of household is alsoreferred to as the first parent.

Education of parent or guardian. –This wasrecorded a“ he highest grade completed inschool. - only grades counted were thoseattended ;.. ~ regular school where parents weregiven formal education in graded public orprivate schools, whether day or night school,and whether attendance was full or part time. A“regular” school is one which advances a persontoward an elementary or high school diploma, ora college, university, or professional schooldegree. Education in vocational, trade, or busi-ness schools outside the regular school systemwas not counted in determining the highestgrade of school completed.

39

APPENDIX Ill

HOUSEHOLD QUESTIONNAIRE AND MEDICAL HISTORY ITEMS

– CONFIDENTIAL - The National Health Survey is authorized by Public Law 652 of the 84th Congress (70 Stat.489; 42 U.S.C. 305). All information which would permit identification of rhe individual will be held strictlyconfidential, will be used only by persons engaged in and for the purposes of the survey and will not be dis-closed or released to others for any other purposes (22 FR 1687).

FORM t4ti5-tiE5-2[11-13-63)

U.S. DEPARTMENT OF COMMERCEBUREAU OF THE CENSUS

ACTING AS COLLECTING AGENT FO@ THEU.S. PUBLIC HEALTH SERVICE

NATIONAL HEALTH SURVEY

2. (a) Address or description of location (include city, zone, and State)

1 ALL II

2 HOW~re~s). . ~elat~ to the head of he hQuseha[d?

(Enter relationahfp to head, for example: wffe, dau~hter, stepeon, gtandaon, mother-in-law, partner, roomer~e wife, etc.)

r _ ASK FOR PARENTS OR GARDIANS OF EC [

7. Where were yau born?

(Check u.S. box or write in name of country)I

9. What is the highest grade you attended in schaal? i Q None

(Circle hfgheat grade attended or mark 8CNone. >8} IElern. . . . 12345678

(If attended, ask): High . . ..l 234

(a) Did you finish this grade (year)? College 1 2 3 4 5+---—- ----- _-q

. n Yes a No

I ,ALL E C HOUSEI+OLDS 1

\ 4. Which of these in came graups represents your tatal combined farni ly incame for the past 12 ‘months, that is,yaur’s, your -- ‘s, etc? (Show Income Flash Card HES-2(b). ) Include income from all sources, such as wages,salaries, rents from praperty, Sacial Security, or retirement benefits, help from relatives, etc.

40

CONFIDENTIAL - The National Health Survey is authorized by Public Law 6.52 o/ FORM APPROVZr.

the 84th Congress (70 Stat. 489; 42 U.S. C. 242c). All in/onnation wbicb wouldBuDGET 13UREAU NO. 68. R620-s4,6

permit identification o/ the individual wiI1 be held strictly confidential, will be used only by persons engaged in

und for the purposes o/ the survey and will not be disclosed or released to others /or any other purposes (22 FR 1687’).

DEPARTMENT OF HES-25 6HEALTH, EDUCATION, AND WELFARE

PUBLIC HEALTH SERVICE (1-5)NATIONAL HEALTH SURVEY

CHILD’S MEDICAL HISTORY - Parent

NAME OF CH!LO (Last, First, MiaHle) SEGMENT SERIAL COL. NO.

(6-1 1)

NoTE: Please complete this form by checking the correct boxes and/or filling in the blanks where applicable.

When you have completed it, keep it until the representative of the Health Examination Survey calls on you

within a few days. If there are some questions you do not understand, please complete the others and the person who

comes for the form wi H help you with the ones that were unclear.

1. SEX I 2. AGE [ 3. DATE OF SIRTH (Monrb. Day, Year)

(12-14)

(15)

(17)

(18)

(21)

(22)

I o Male z o Female

4. PLAcE OF BIRTH (C ity or TOW Stnte) 5. WAS THIs CHILO BORN IN A HOSPITAL?I m Yes 213N0 3 u Don’t know

IF YES: ( Question 5)

A. About how long did you (the mother) stay in the hospital after the baby was born?

t u 1 week or less 2 u 1 to 2 weeks 3 u Over 2 weeks 4 0 Don’t know

B. If mother stayed over 1 week, what was the teason for staying that long?

C. About how long did the baby stay in the hosp;al?

t u I week or less 2 u 1-2 weeks s u Over 2 weeks 4 u Don’t know

D. If the baby stayed o_v~r 1 week, what waa the reason for staying that long?

G. ABOUT HOW MANY POUNDS DID THE BABY WEIGH AT BIRTH?

I u Under 5 2 m 5-10 3 I_J Over 10 4 u Don’t know

8. WAS THERE ANYTHING UNUSUAL OR WAS ANYTHING WRONG WITH THE BABY WHEN HE( SHE) WAS BORN?

I n Yes 2uN0 s u Don’t know

IF YES:

A. What was the. matter?

B. What did the doctor say caused this?

9. WHILE YOU (THE MOTHER) WERE PREGNANT WITH THIS CHILD DID YOU HAVE ANY MEDICAL PROBLE&IS

OR COMPLICATIONS?

I a Yes 2 UNO 3 0 “Don’t knowIF YES, what kind of trouble did you have?

41

(27)

(31)

(34)

(36)

(37)

11. BEFORE THIS BABY WAS BORN, WHILE YOU (THE MOTHER) WERE PREGNANT-WITH THIS CHILD, DID YOU

(THE MOTHER) SEE A DOCTOR?

I I_J Yes 20N0 3 0 Don’t knowIF YES:

A. About how many months pregnant were you when you first saw a doctor?1 u Less than 3 2a3t06 3 D Over 6 4 0 Don’t know

B. About how many times altogether did you see a doctor while you (the mother) were pregnant?t u None 2nlto3 3 m 4 or more d u Don’t know

12. DID YOU (THE MOTHER) HAVE ANY TROUBLE WITH THE PREGNANCY OR BIRTH OF THIS CHILD?

f n Yes 2uNo 3 u Don’t know

IF YES, what was the trouble?

15. W–AS THE CHILD BREAST FED?

i m Yes 2uN0 3 u Don’t know

A. IF YES, for about how many months was he(she) breast fed?

1 u Less than 1 znlto6 3 0 Over 6 q u Don’t know

B. When breast feeding was stopped, how easily did the baby accept the change?

1 u No problem 2 D Some problem 3 U Considerable problem

16. ABOUT HOW OLDWAS THE CHILD WHEN HE(SHE) FIRST WALKED BY HIMSELF?

i u Under 1 year old z U Between 1 and l% years old3 ~ Over 1%’ years old q u Don’t know

17, AEGJT HOW OLD WAS THE CHILD WHEN HE(SHE) SPOKE HIS FIRST REAL WORD?

I n Under I year old 2 u Between 1 and llA years old3 U Over 1% years old A u Don’t know

la. CHILDREN LEARN TO CO THINGS LIKE EATING BY THEMSELVES AND TALKING AT DIFFERENT AGES. DO

YOU THINK THIS CHILD WAS ESPECIALLY ~ IN LEARNING TO DO THINGS, ABOUT AvER AGE, OR SOME-WHAT SLOWER THAN OTHER CHILDREN?

I U Faster than other children 2 u About the same 3 a Slower d u E@n’t know

19. DID HE(SHE) GO TO KINDERGARTEN OR NURSERY SCHOOL BEFORE ENTERING THE FIRST GRADE?

I O Yes 2~No s o Don’t know

32. HERE IS A LIST OF DISEASES THAT CHILDREN SOMETIMES HAVE. HAS THIS CHILD EVER HAD:

If yes, about how

old at the time?

H. Epilepsy? 1 Cl yes+ Age_ 2uN0 3 ❑ Don ‘t know

J. Cerebral palsey? i n Yes+- Age 2uN0 3 u Don’t know,

35. HERE ARE SOME OTHER KINDS OF ILLNESSES OR CONDITIONS SOME CHILDREN HAVE. HAS YOUR CHILDEVER HAD:

E. A heart murmur?F. Anything wrong with

his(her) heart?

t I_J Yes 2uN0 s o Don’t kaowi D Yes 2uN0 s o Don’t know

42 *US. GOVERNMENTPRINTINQOFFICE: 1977-260.937:28

Series 1.

Series 2.

Series 3.

S6n+es 4.

Series 10.

Series 11.

Series 12.

Series 13.

Sw”es 14.

Sa+es 20.

Series 21.

S-”es 22.

VITAL AND HEALTH STATISTICS PUBLICATION SERIES

Formerly PublicHealth Service PubliaetionNo. 1000

Prognams and collectwn procedures. —Reports which describe the general programs of the NationalCenter for Health Statistics and its offices and divisions, data collection methods used, definitions,and other material necessary for understanding the data.

LMta evaluation and methods research. - Studies of new statistical methodology including: experi-mental tests of new sttrvey methods, studies of vital statistics collection methods, new analytical

techniques, objective evaluations of reliability of collected data, contributions to statistical theory.

Artalvtical studies. -Reports presenting analytical or interpretive studies based on vital and healthstatistics, carry$ig the analysis further than the expository types of reporta in the other series.

Documents and committee reports.— Final reports of major committees concerned with vital andhealth statistics, and documents such as recommended model vital registration laws and revisedMrth and death certificates.

Data j%rn the Health Interv&w Survev. —Statistics on illness, accidental injuries, disability, useof hospftal, medical, dental, and other services, and other health-related topics, based on datacollected in a continuing national household fnterview survey.

Data from the Health Examination Survey. —Data from direct examination, testing, and measure-ment of national samples of the civilian, noninstitutional population provide the basis for two typesof repcwts: (1) estimates of the medically defined prevalence of specific diseases in the UnitedStates and the distributions of the population with respect to physical, physiological, and psycho-logical characteristics; and (2) analysis of relationships among the various measurements withoutreference to an explicit finite universe of persons.

LWa J&om the Institutional Populatwn Surveys. —Statistics relating to the health characteristics ofpersons in institutions, and their medical, nursing, and personal care r~eived, based on nationalsamples of establishments providing these services and samples of the residenta or patients.

DUti @om the Hospital Discharge Survey. —Statistics relating to discharged patienta in short-stayhospital% based on a sample of patient records in a national sample of hospitals.

DOta on health resources: man#owr and facilities. —Statistics on the numbers, geographic distri-bution, and characteristics of health resources including physicians, dentists, nurses, other healthoccupations, hospitals, nursing homes, and outpatient facilities.

Data on mortality. —Various statistics on mortality other than as included in regular annual ormonthly reports-special analyses by cause of death, age, and other demographic variables, alsogeographic and time series analyses.

Data on natality, marriage, and divorce. —Various statistics on natality, marriage, and divorceother than as included in regular annual or monthly reports-pecial analyses by demographicvariables, also geographic and tfme series analyses, studies of fertility.

Data from the National Natdity and Mortality Surveys. — Statistics on characteristics of birthsand deaths not available from the vital records, based on sample surveys stemming from theserecords, including such topics as mortality by socioeconomic class, hospital experience in thelast year of life, medfcal care during pregnancy, health insurance coverage, etc.

* For a list of titles of reports published in these series, write to: Office of Information,.

National Center for Health StatisticsPublic Health Service, HIU4Hyattsville, Md. 20782