Data from the

NATJC)NAL HEALTH SURVEY

Skeletal Maturity of Children

641 years:

Racial, Geographic Area,

and Socioeconomic Differentials

United States

Skeletal age (hand-wrist) and bone-specific skeletal ages (as

determined using the Health Examination Survey standard based

on the Greulich-P yle Radiographic Atlas) of boys and girls 6-11

years of age, by chronological age, race, geographic region,

population size or land use of area of residence, annual family

income, and education of parent.

DHEW Publication No. (HRA) 76-1631

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

Public Health Service

Series 11

Number 149

Health Resources Administration

National Center for Health Statistics

Rockville, Md. October 1975
Library of CongressCataloging in Publication Data

Roche, Alexander F.

Skeletal maturity of children 6-11 years: Socioeconomic differentials.

(National Center for Health Statistics. Data from National Health Survey, series 11, no.

149) (DHEW publication no. (HRA) 76-1631)

Includes bibliographical references.

Sqpt. of Dots. no.: HE 20.2210:11/149

1. Children-Growth-Testing. 2. Bone–Growth–Statistics. 3. Children in the United

States–Anthropometry. I. Roberts, Jean, joint author. II. Hamill, Peter V. V., joint author.

III. Title. IV. Series: United States. National Center for Health Statistics. Vital and health

statistics. Series 11: Data from the National Health Survey. Data from the health

examination survey, no. 149. V. Series: United States. Department of Health, Education,

and Welfare. DHEW publication no. (HRA) 76-1631. [DNLM: 1. Age determination by

skeleton. 2. Bone development. 3. Hand—Growth & development. 4. Socioeconomic factors.

W2 A N148vk no. 149]

M407.3.A347 no. 149 [RJ13] 312’.0973s [312’.6]

ISBN 0-8406-0030-5 75-18049

For sale by the Superintendent of Documents, U.S. Government Prfntfng Office, Washington, D.C. 20402-Price $1.46
NATIONAL CENTER FOR HEALTH STATISTICS

HAROLD MARGULIES, M.D., Acting Director

ROBERT A. ISRAEL, Acting .Deputy Director

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

ELIJAH L. WHITB, Associate Director for Data Systems

EDWARD E. MINTY, Associate Director for Management

PETER L. HURLEY, Acting Associate Director for operations

JAMES M. ROBEY, Ph.D., Associizte Director for Program Development

ALICE HAYWOOD, Information Oflicer

DIVISION OF HEALTH EXAMINATION STATISTICS

ARTHUR J. McDOWELL, Director

JEAN-PIERRE HABICHT, M.D., Ph.D., Special Assistant to Director

PETER V. V. HAMILL, M.D., Medical Adviser

JEAN ROBERTS, Chiej Medical Statistics Brarzch

ROBERT S. MURPHY, Chief Suruey Planning and Development Branch

COOPERATION OF THE BUREAU OF THE CENSUS

In accordance with specifications established by the National Center for

Health Statistics, the Bureau of the Census, under a contractual agreement,

participated in the design and selection of the sample, and carried out the

first stage of the field interviewing and certain parts of the statistical

processing.

Vital and Health Statistics-Series 1 l-No. 149

DH EW Publication No. (H RA) 76-1631

Library of Congress CutaZogCurd Number 75-18049
CONTENTS

Page

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

ExaminationIvlethod . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Field Radiography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Training of Assessors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Assessment Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Skeletal Age (Hand-Wrist) Findings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Race . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Geographic Region . . . . . . . . . . . . . . . ... . . . . . . . . . . . . . . . . . . . . . . . . . 15

Urban-Rural . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Socioeconomic Factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Bone-Specific SkeletalAge Findings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Race . . . . ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Geographic Region ...:.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Income . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Range ofBone-Specific Skeletal Ages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Onset ofOssification Findings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Race . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Geographic Region . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Socioeconomic Factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Race . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Geographic Region . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Socioeconomic Factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... . . . . . 36

ListofDetailed Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Appendix I. StatisticalNotes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

Survey Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

Reliability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
CONTENTS – Con.

Page

SampIing and Measurement Error . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

Expected Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

SmallCategories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Appendix II. Demographic andSocioeconomicTerms . . . . . . . . . . . . . . . . . . . . 76

Appendix III. Reliability of Assessments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

Area Skeletal Ages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

Bone-Specific Skeletal Ages.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

Factors Influencing Replicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

SYMBOLS

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

Category not applicable ------------------------------

Quantity zero ---------------------------------------------

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

Figure does not meet standards of

reliabilityy or precision ----------------------------

---

. . .

0.0

*

iv
SKELETAL MATURITY

iDF CHILDREN 6-11 YEARS:

RACIAL, GEOGRAPHIC AREA, AND

SOCIOECONOMIC DIFFERENTIALS

A. F. Roche, M.D., Fels Research Institute, Jean Roberts, and Peter V. V. Hamill, M.D.,

Division of Health Examination Statistics

INTRODUCTION

This report contains national estimates of the

levels of skeletal maturity in the hand-wrist of

noninstitutionalized children in the United

States 6-11 years of chronological age by race,

area of residence, and socioeconomic background, as determined in the Health Examination Survey of 1963-65. The previous report on

these radiographic findings,l which was limited

to the sex differences in skeletal maturity in

relation to chronological age, contains a more

comprehensive description of the nature of

skeletal maturation and of the assessment

method used in the Survey.

The Health Examination Survey is one of the

major programs of the National Center for

Health Statistics, authorized under the National

Health Survey Act of 1956 by the 84th Congress

as a continuing Public Health Service function to

determine the health status of the population.

In carrying out the intent of the National

Health Survey,z four different types of survey

programs are used. The Health Interview Survey

collects health information from samples of

people by household interview with a responsible adult and is focused primarily on the impact

of illness and disability within various population groups. The programs in the Divisions of

Health Resources Utilization Statistics and

Health Manpower and Facility Statistics obtain

health data as well as health resource and

utilization information through surveys of hospitals, nursing homes, and other resident institutions, and also data on the entire range of

personnel in health-related occupations. The

Health Examination Survey collects health data

by direct physical examination, tests, and measurements performed on samples of the population. The latter program provides the best way

of obtaining the actual prevalence of certain

medically defined illnesses. It is the only effective way to secure information on unrecognized

and undiagnosed conditions and on a variety of

physical, physiological, and psychological measures within the population. Also it collects

demographic and socioeconomic data on the

sample population under study to which the

examination findings may be related.

The Health Examination Survey (HES) is

organized as a series of separate programs, or

cycles, each of which is limited to some specific

segment of the United States population and to

specific aspects of health. In the first cycle, the

prevalence of certain chronic diseases and the

distribution of various physical and physiological measures were determined on a cross section

of the defined adult population, as previously

described.3 *4

In “;he program on which the findings in

this repm-twm+ased, a probability sample

representative of the approximately 24 million

noninstitutionalized children aged 6-11 years

in the United States was selected and

1
examined. The examination in this crosssectional study primarily assessed health factors

related to growth and development. It included

an examination by a pediatrician and by a

dentist, tests administered by a psychologist,

and a variety of tests and measurements administered by a technician. A more complete description of the survey plans, sample design,

examination content, and operation of the

Survey has been published.5

Field collection operations for this cycle were

started in July 1963 and completed in December

1965. There were 7,417 children selected in the

sample, of whom 7,119, or 96 percent, were

examined. This national probability sample is

representative, and those examined are closely

representative of the approximately 24 million

noninstitutionalized children aged 6-11 years in

the United States with respect to age, sex, race,

region, size of place of residence, and rate of

change in size of place of residence from 1950

to 1960. Of the children examined, 157 were

not radiographer or had radiographs taken for

the Survey that were not suitable for assessment.

Thus, the skeletal maturity estimates for United

States children 6-11 years are based on the

remaining 6,962 children, or 94 percent of the

original sample.

The examining team gave each child a standardized examination during hk single visit in the

mobile units specially designed for use in the

Survey. Demographic and socioeconomic data on

household members as well as medical history,

behavioral, and related data on the child to be

examined were obtained from his parents prior

to his examination. Ancillary data were requested from the school attended by the child,

including his grade placement, school behavior,

adjustment, and health problems: Birth certificates for verification of the child’s age and

information related to his condition at birth

were obtained ajso.

The present analysis concerns differences in

skeIetal maturity levels for the United States

population aged 6-11 years, grouped according

to race, region, and socioeconomic status. The

general concept of skeletal maturity, the method

by which radiographs were taken and later

assessed, and the quality control measures used

have been described and discussed.1 The present

findings provide normative national data. They

are interpreted in regard to the health significance of skeletal maturity status and compared

with findings from other studies. Not all relevant

reports have been included in the literature

review, some because the sample size was inadequate but others because of inadequate documentation concerning the repeatability and

comparability of the skeletal age assessments. In

later reports, the skeletal ages of these children

will be considered in relation to body size, body

composition, and other variables.

A brief description of the sample design,

quality control methods, reliability of the data,

as well as population and sampling error estimation procedures used for the findings of this

study is contained in appendix I. Definitions of

the demographic terms used in the report are

included in appendix II, and an evaluation of the

reliability of the assessments is shown in appendix III.

EXAMINATION METHOD

At each of the 40 preselected locations

throughout the United States used consecutively

in this cross-sectional study, the children were

brought to the centrally located mobile examination center for a standardized examination

that lasted about 2?42hours. Six children were

examined in the morning and six in the afternoon. When each child entered the mobile

center, his oral temperature was taken and a

screening for acute illness was made. If such

illness were detected, the child was sent home

and reexamined later. Each examinee next

dressed in shorts, cotton sweat socks, and a light

sleeveless shirt and proceeded to a designated

but different station for the examination. The

sequence of elements in the examination differed for each child, so that the six could be

examined simultaneously during the half day.

The same examiners–physician, dentist, psychologist, and specially trained technicians—

conducted their parts of the examination in

essentially the same manner for each child. The

time of each part of the examination was

recorded, but there is no reason to believe that

diurnal or sequence effects would be present in

the composition or quality of the radiographic

data.

2
Field Radiography

Each child was scheduled to have a 10” X 12”

radiograph taken of the right hand and wrist for

which the positioning was otherwise in accordance with specifications in the GreuIich-Pyle

Atlas.G Some radiographs were made using other

film sizes when the 10“ X 12“ size was scarce;

this would not have influenced the findings.

Technically inadequate films could be repeated

because they were developed immediately in the

field. Thus, each child’s record contains a single

radiograph showing the dorsopalmar view of his

entire hand-wrist with its full complement of

ossifying parts, at his examination age.

The decision to radiograph the right handwrist rather than the left, which is the more

frequent anthropometric practice, was made on

the advice of anthropologist consultants who

were interested also in the use of related

measurement data for equipment design in

which right-side measurements were preferred.

When the selected plates from GreuIich-Pyle

Atlas standards and those from other sources

were reproduced in the HES Standard, they

were reversed photographically so that they

could be used in right-side assessments. Previous

reported research7 on lateral differences in the

skeletal maturity of the hand-wrist, either for

the area as a whole or bone by bone, has shown

that these are too small to be of practical

importance.

Training of Assessors

The assessment of skeletal age from the

hand-wrist radiographs of children 6-11 years of

age in the Health Examination Survey of

1963-65 was made by six medical students at

Case Western Reserve University, one of whom

was an instructor specializing in anatomy. This

work was done under contract for the National

Center for Health Statistics, with Dr. P. Wesley

Dupertius as Project Director. Training of the

assessors and implementing the related quality

control procedures were done in the meticulous

manner previously described under the direction of Dr. S. I. Pyle. When the ratings and

reliability for the new assessor were in good

agreement with those of Dr. Pyle (the majority

of differences within 4 months) the new assessor

started his assessments of the survey radiographs. Reported evidences suggests that, at the

end of the training procedure, the interobserver

and intraobserver differences in skeletal maturity ratings were similar to those for experienced

assessors.

Assessment Pr6cedure

The radiographs were assessed by comparison

with prints of the series of standards for the

male hand-wrist selected from those in the 1959

Greulich-Pyle AtlasG and other sources. These

were reversed so that they appeared to be of the

right hand-wrist as shown in the 1971 Radiographic Standard of Reference of Pyle, Waterhouse, and Greulich.g This standard contains the

male skeletal age equivalents that were used

during the assessment of Cycle II radiographs

(ages 6-11 years), with some very slight modification to smooth the skeletal age trend for a few

of the bones.

The readers did not have access to the

chronological age, sex, or other information

about the chiId. Each bone was assessed separately and interpolation was made between the

standards to monthly intervals when this appeared appropriate.

As a quality control measure and to permit

determination of the level of reliability of the

assessments throughout this study, independent

replicate assessments were obtained on approximately 1 out of each 11 films. One randomly

selected radiograph in each 23 was rated independently by another assessor for a measure of

interobserver variability and 1 randomly selected

radiograph among each 20 was rated independently a second time by the same reader to give a

measure of intraobserver variability. The time

lapse between the first rating and the reassessment was sufficiently long that there was little

likelihood of recall. Furthermore, there was no

indication to the assessor that he was making a

reassessment. Information on the degree of

reliability of assessments from this survey has

been published.1

The order in which the bones were assessed

within each radiograph was the same as that in

which they are listed in table A. This table ako

shows the minimum and maximum individual

bone-specific skeletal ages allowable in this

3
Table A. Minimum and maximum acceptable skeletal ages (in

months) using the HES Standard

Hand-wrist bone

Radius . . . . . . . . . . . . . . .

Ulna . . . . . . . . . . . . . . . .

Cavitate . . . . . . . . . . . . . .

Hamate . . . . . . . . . . . . . . .

Triquetral . . . . . . . . . . . . .

Lunate . . . . . . . . . . . . . . .

Scaphoid . . . . . . . . . . . . . .

Trapezium . . . . . . . . . . . . .

Trapezoid . . . . . . . . . . . . .

Metacarpal I . . . . . . . . . . . .

Metacarpal lo . . . . . . . . . . . .

Metacarpal ill . . . . . . . . . . .

Metacarpal IV . . . . . . . . . . .

Metacarpal V . . . . . . . . . . .

Proximalphalanxl . . . . . . . .

Proximal phalanxll-V . . . . . .

Middle phalanx ll-lV . . . . . . .

Middle phalanx V . . . . . . . . .

Distal phalanxl . . . . . . . . . .

Distal phalanx II, V . . . . . . . .

Distal phalanx Ill . . . . . . . . .

Distal phalanx IV . . . . . . . . .

Pisiform . . . . . . . . . . . . . .

Adductor sesamoid . . . . . . . .

Flexor sesamoid . . . . . . . . .

IEzEizz

Skeletal age in months

15

69

--

...

17

35

68

51

68

25

17

16

17

24

33

15

23

39

15

39

22

32

110

146

158

228

215

197

197

197

197

197

197

197

191

215

209

209

215

215

209

209

209

191

191

191

191

197

197

197

1Minimum age (according to standard) of tha radio-opacity

of the epiphysis or carpal.

2One month below “adult” age.

study. The lower limit for the bone-specific

skeletal age was arbitrarily set midway in skeletal age (hand-wrist) between the last standard

in which the particular bone was not radioopaque and the first in which it was radioopaque. Exceptions were made for the three

later ossifying bones–the pisiform and the adductor and flexor sesamoids–for which minimum ages allowed were 2 months above the last

standard in which they were not radio-opaque.

There are limits also at the upper end of the

range when bones become adult. Only the

designation “adult,” and not a skeletal age in

months, can be assigned to a bone in which

maturation is complete. Median ages in months

from the HES Standard at which this occurs in

boys were used as the skeletal age for each bone

beyond which only the designation “adult”

could be applied. The maximum allowable values 1 month below the “adult” skeletal age are

shown in table A.

As expected, withih chronological age groups,

the skeletal ages assigned to girls were more

advanced than those assigned to boys. This

occurs because, although boys and girls pass

through the same skeletal maturity stages, girls

tend to mature more rapidly than boys. The

female equivalent skeletal ages were determined

during the preparation of the HES Standard, but

were not used in the assessment of the Survey

radiographs. The method by which these female

equivalent skeletal ages were obtained has been

described in detail by Pyle et al.g

The skeletal age data for girls in the detailed

tables of this report are given both in terms of

the male standards, as originally assessed, and in

terms of the female equivalent skeletal ages.

However, the findings for girls in the text are

limited to the female equivalent skeletal ages.

The skeletal age values for the whole hand-wrist

for boys and girls in this report were determined

by computer from the original bone-specific

assessments by averaging the ages assigned the

hand-wrist bones for each child.

SKELETAL AGE (HAND-WRIST)

FINDINGS

Among both boys and girls 6-11 years of age

in the United States (considering only the

female equivalent values for girls), skeletal age

(hand-wrist) was found, on the average, to be

consistently less than chronological age. The

mean sex-associated differences increase steadily

with chronological age. Comparison of skeletal

age for boys with the female equivalent values

for girls shows close agreement (mean difference

less than 1 month) among children 7 and 8 years

of age at their last birthday, while among

younger and older children of 6 and 9-11 years,

the meris for boys are substantially less advanced than those for girls, by 2 to 3 months.

Boys showed no consistent pattern in the

variability of skeletal age (hand-wrist) with

chronological age, but older girls were slightly

more variable than younger girls in this respect.

Except at ages 9 and 10 years, boys showed

4
slightly greater relative variability than girls in

their skeletal ages. These national estimates,

which have been reported previously, 1 are based

on data from the National Health Examination

Survey of 1963-65 in which assessments of

hand-wrist radiographs were made using the HES

Standard based primarily on the Greulich-Pyle

Radiographic Atlas.b

able environmental factors—e.g., protein intake,

temperature–on skeletal maturation in children.

This report contains information on the

racial, geographic region, urban-rural, and socioeconomic differentials in the skeletal maturity

of United States children. These findings are

compared with relevant research findings from

previous studies.

Pre;io& international research has shown “

clearly that children of different racial groups Race

vary in body size and in levels of skeletal and

sexual maturity at corresponding chronological

ages,lo‘15 Factors influencing the rate of the

apposition or resorption of bone in skeletal

maturation are related to genes, nutrition, illness, or climate. Only in a few studies, however,

have the possible effects of these factors been

separated. Interactions between these factors

make it difficult to draw definitive conclusions

from reported findings outside the context of

animal experimentation. Knowledge is almost

entirely lacking concerning the effects of specific groups of genes—e.g., autosomal, sexIinked–or the effects of quantitative, measurThe skeletal maturity of white boys and girls

6-11 years of age generally tends to be somewhat less advanced than that of Negro boys and

girls in the United States of corresponding

chronological age. The number of children of

other races in this country, and hence in the

study sample, is too small to provide reliable

estimates for this heterogeneous segment of the

population.

Among white boys, the mean skeletal age

(hand-wrist) is consistently lower than that of

their Negro counterparts, except for those 10

years of age at their last birthday (figure 1 and

BOYS

6 7 8 9 10 11

CHRONOLOGICAL AGE IN YEARS

r

GIRLS

5 (Female equivalents)

I

Negro

White

–15

t

I I I I I I I

6 7 8 9 10 11

CHRONOLOGICAL AGE IN YEARS

Figure 1, Mean difference in months between skeletal age (hand-wrist) and chronological a9e for white and Negro boys and 9irk by

chronological age in years: United States, 1963-65.

5
table 1). At all but 6 and 8 years (chronological

age) where the skeletaI age means for Negro

boys exceed those for white boys by more than

4 months, the mean differences between the

races in skeletal age are small (1 to 2 months).

With the size and design of the sample used in

this study, they could easily reflect sampling

variability alone (i.e., the differences are not

statistically significant at the 5-percent probability level using standard parametric tests—see

appendix I). These differences are also not

significant when data for all ages are combined.

The mean skeletal age (hand-wrist) of white

girls (female equivalent values) also lags behind

that for their Negro counterparts, except for

those 8 years of age at their lastbirthday where

the mean values are identical. For the remainder

of the girls, mean differences vary between O.7

month at chronological age 11 years and 2.7

months at age 10 years. All of these differences

are within the 95-percent confidence limit for

such estimates and hence could reflect sampling

variability alone. When data are combined for

6-11 years, these white-Negro differences are

statistically significant for boys but not girk.

When indirect adjustments are made for any

differences in the age distributions among white

and Negro children (assuming that the national

age-specific mean values apply identically in

both racial groups), the contrast in skeletal

maturity betwe en the two racial groups is even

more clear. This is shown for all ages combined

in figure 2.

5!-

-5 !-

WHITE NEGRO

Figure 2. Difference between actual and axpected mean skeletal

age (hand-wrist) for whita and Negro boys and girls 6-11

years of chronological age: United States, 1963-65.

6

Among white children, girls are genedly

more advanced than boys in their skeletal age

(hand-wrist) except at chronological age 8 years

when the mean values are identical (figure 3).

The differences in mean skeletal age for the

remainder range from 1.2 months at age 7 years

to 4.3 months among the oIdest children at age

11 years. Among the youngest and oldest

children—those of chronological ages 6, 10, and

11 years–the mean differences exceed the

95-percent confidence limit for such estimates

and hence are not likely to be due to sampling

variability alone.

Negro girls of chronological ages 9-11 years

are also generally more advanced in skeletal age

than Negro boys by mean values of 2.9, 7.0, and

3.0 months, respectively. The differences at 9

and 11 years are too small to be considered

statistically significant (at the 5-percent probability level). Among younger Negro children of 6

and 7 years (chronological age), the mean

differences in skeletal age between boys and girls

are negligible, but among those 8 years of age at

their last birthday, Negro boys were more

advanced than Negro girls in skeletal age (female

equivalent values) by more than 4 months.

The variation in skeletal age (hand-wrist)

among children of chronological ages 6-11 years

in this country shows no consistent pattern of

racial differences. White boys of chronological

ages 6, 8, and 9 years are relatively more variable

in skeletal age than Negro boys while at ages 7,

10, and 11 years the reverse was found (figure 4

and table B). White girls at alIages except 7 and

10 years, where the differences were small, are

somewhat less variable in this respect than Negro

girls. The pattern of relative variability between

boys and girls differs for white and Negro

children. Among white children, boys showed

greater relative variability in skeletal age than

girls in four of the six age groups-6-8 and 11

years–while among Negro children, boys were

Iess variable than girk in skeletal age at aIIbut 7

years of age. The patterns of sex differences in

variability, across age, were more regular in

white than in Negro children. This greater

stability in the white children probably reflects

the greater sample size for them.

O~herstudie; (white). –Comparison with racial

findings

children

for skeletal maturity- of United States

from the present national survey is
WHITE

5

0

%..

●✎✎✎✎

●☛

–5

–lo

(Female equivalents)

–15

;~

6 7 8 9 10 11

CHRONOLOGICAL AGE IN YEARS

t

I t I i I 1 I

6 7 8 9 10 11

CHRONOLOGICAL AGE IN YEARS

Figure3, Mean difference in months between skeletal age (hand-wrist) andchronologiml age forwhite boys andgirls and Negro boys

andgirls, by chronological age in years: United States, 1963-65.

20

15

10

5

0

BOYS GIRLS

....

‘.*

“.

‘.

t I I I 1 I

6 7 8 9 10 11

CHRONOLOGICAL AGE IN YEARS

20

15

10

5

0

-’ z

6 7 8 9 10 11

CHRONOLOGICAL AGE IN YEARS

Figure4, Relative variability in skeletal age (hand-wrist) among white and Negro boys andgirls, bychronological ageinyears: United

States, 1963-65.

7
Table B. Coefficients of variability of skeletal agewithinchronological age groups

Chronological aga

6years . . . . . . . . . .

7years . . . . . . . . . .

8years . . . . . . . . . .

9years . . . . . . . . . .

10yaars . . . . . . . . .

Ilyaars . . . . . . . . .

Boys I

Girls

1

White Negro White Negro

Coefficient of variation (100 sx/X)

15.3

13.4

12.4

10.8

9.0

10.5

13.6

14.7

10.0

10.0

9.2

10.9

13.9

12.0

10.8

11.7

12.6

9.4

14.6

11.5

12.8

14.6

12.5

11.0

limited primarily to previous studies among

various subgroups of children in this country.

The skeletal maturity (hand-wrist) data for

white children from seven previous studies in

this country (some longitudinal and some at a

single point in time) and the United States

estimates for 1963-65 from the present national

cross-sectional study are shown in figures 5-8.

Data from the previous studies have been adjusted to a common Greulich-Pyle zero line to

facilitate comparisons among them and with the

present study. Data from the previous studies

relate to mean, median, or approximate modal

values of skeletal age (hand-wrist) within chronological age groups and are shown as the

difference between skeletal and chronological

1.0 r

— Flory (1936)

--- Todd (1937)

.. . . . . . Simmons (1944)

...-- ..

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

....”

. .. .. ..

.. ... A ““””

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

....-”” /\ ,/’,

/\ \“ # -,

.~ \ /’ \ --- \,/ \.

.,.5 ~

6 7 8 9 10 11

CHRONOLOGICAL AGE IN YEARS

Figure 5. Differences between skelatal and chronological ages of

boys by chronological age in years, in studies of Flory

(1936), Todd (1937), and Simmons (1944).

--- Greulich and Pyle (1959) and Bayley (1962),

1.0,

[

------ Johnston (1962)

--- Fry (1966)

--. Maresh (1971) . . . . . . ....-’- /-

0.5 - — United Statea children /.

(1963-65) .......

#.... -

... .. .

/

0 - ...”.

/= /’

----=. ,-___e --

: [:*

-1.5 I

1 1 1 1 r

6 7 8 9 10 11

CHRONOLOGICAL AGE IN YEARS

Figure 6. Differences between skeletal and chronological ages of

boys, by chronological aga in years, in studies of Greulich

and Pyle (1959), Bayley (1962), Johnston (1962), Fry

(1966), and Nfarash (1971), and for United States children

(1963-65).

— Flory (1936)

--- Todd (1 937)

.. . .. .. . Simmons (1944)

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

. . . .. . .

0 -

-%. .. ..

#..... - ... .

. .. . ..

<

/.

g

/--.,~.

.....

u

/

~

..... ---- /

–0.5 - .... *tiO----=-

i Y

./

-1.5

Ill

i

Y

WI

-2.0

I

-2.56-

CHRONOLOGICAL AGE IN YEARS

Figure 7. Differences between skelatal and chronological ages of

girls (female equivalent values for the former), by chronological age in years, in studies of Flory (1936), Todd (1937),

and Simmons (1944).

age within chronological age groups in these

figures. Values above the zero line show acceleration in skeletal maturity (skeletal age exceeds

chronological age) and those below the zero line

show retarded skeletal age. The 1959 GreulichPyle standards6 were selected from radiographs

of white children of upper socioeconomic status

8
(Female equivalent values)

--- Greulich and Pyle (1959)

1.0 - . ... . Bayley (1962)

~ . . . . . . Johnston f 1962)

G --- Fry (1966)

~

--- Maresh (1971)

0.

2UI — United States children (1963-6E

Occ

ma

=W

u> o

i~~ ‘;’*

,. . . .. .. . ..=~77k.~5F+~

w .

-1.0

6 7 6 9 10 11

CHRONOLOGICAL AGE IN YEARS

Figure 8. Differences between skeletal and chronological ages of

girls (female equivalent values for the former) by chronological age in years, in studies of Greulich and Pyle (1959),

Bayley (1962), Johnston (1962), Fry (1966), and Maresh

(1971 ), and for United States children (1963-65).

living in Cleveland. These children were born

between 1917 and 1942 and were radiographed

close to birthdays and half-birthdays, as previously described.1 The method by which these

standard plates were selected from the 100

radiographs available for each sex at each age is

described in the Atlas of Greulich and PyIe.6

The mixed longitudinal data of FIoryl 6 were

obtained from white Chicago children of aboveaverage socioeconomic status who were born

between 1911 and 1923 and were radiographed

close to each birthday. Flory selected from the

100 radiogmphs available for each sex at each

age (except at 6 and 7 years when at least 80

radiographs were available) those radiographs

that he considered best represented the central

tendencies of skeletal maturity in his groups.

The selected radiographs are about 1 year

retarded in maturity in comparison with corresponding GreuIich-PyIe standards (figures 5 and

7). Simmonsl 7 reported data from Cleveland

children, most of whom were included in the

sample studied by Greulich and PyleG and who

had been radiographed near each birthday. The

sample size varied from 154 to 206 for each year

of age for each sex. The means reported by

Simmons, after adjustment for the use of Todd

standards,l S were within 0.5 year (skeletal age)

of the Greulich-Pyle standards.

Toddl s published standards

white Cleveland children of all

derived from

socioeconomic

levels. These chiIdren were born between 1920

and 1930 and radiographer near each birthday

and half-birthday. The sample size within each

age-sex group varied from 35 to 94 children. The

standard plates were chosen to represent the

central tendencies for skeletal maturity Ievel

within these age-sex-specific groups. The Todd

standards (from all socioeconomic groups) were

at lower levels than those of Greulich and Pyle

(from upper socioeconomic groups). The Todd

values were also lower than the mean skeletal

maturity levels reported by Simmons (from

upper socioeconomic groups) but exceeded

those of Flory (from average socioeconomic

groups) .

Bayleyl 9 reported data from the Harvard

Growth Study of white children of middle

socioeconomic status, living in Boston, born

between 1930 and 1939, and examined near

each birthday. The sample size varied from 63 to

67 in each age-sex group. The mean skeIetal ages

(Greulich-Pyle) for these children were very

c 10 se to their mean chronological ages.

Johnstonz 0 reported mixed longitudinal data

for middle-class white Philadelphia children born

between 1937 and 1955. The ethnic strains in

this sample were (in order of frequency) Italian,

Scotch, Irish, English, Polish, Russian, and

Ukranian, with many Jews included among the

East Central European peoples.21 These children were radiographed at random chronological

ages, and the sample size varied from 23 to 51

for each annual interval in each sex. All mean

skeletal ages were within O.5 year of the

Greulich-PyIe standards except in 10- and 11-

year-old boys who were about 0.6 to O.7 year

ahead of the Greulich-Pyle standards (figure 6).

It would be tempting to conclude that the

skeletal advancement of these boys reflects their

ethnic origins, but this factor should then have

operated equally in girls which it did not (figure

8).

Cross-sectional skeletal age data from white

Nebraska children of middle socioeconomic level

have been reported by Fry (1966).2 z These

children were born between 1950 and 1960 and

were radiographed at random ages. The sample

included 25 children of each sex within each

annual interval. The means were below the

Greulich-Pyle standards, particularly in 6- and

7-year-old boys. Mareshz 3 reported mixed lon9
gitudinal data from upper middle class white

Denver children. The children were born between 1915 and 1964, but most of the radiogmphs were taken after 1947 and close to

birthdays and half-birthdays. The sample size

ranged from 39 to 57 for each 6-month interval

in each sex. The median skeletal ages for these

children were about O.5 year below GreulichPyle standards from 6-11 years.

Comparable findings for United States white

children in the present national study, that

would be closely representative of all socioeconomic groups in the country, show a distinct

pattern of increasing retardation in skeletal

maturity with chronological age. This tendency

was evident among boys in the earlier studiesl G-1g and is in sharp contrast to the agepattern among boys in the more recent studies.19 ~z0Y22~z3 The increasing retardation or lag

of skeletal age behind chronological age as

chronological age increases among U.S. children

differs from the findings in both earlier and

more recent studies among selected groups of

girls. The findings for 10- and 11-year-old

children from the present national study are

more consistent with those of Floryl 6 than with

those of the other studies.

The present national study as well as the

previous studies among more geographically

limited groups of the United States population

show that sex differences in mean levels of

skeletal maturity were small. This does not

indicate that girls did not mature more rapidly

than boys, but that, when assessments were

made against sex-appropriate standards, the differences between the mean skeletal ages for the

two sexes were slight. The exceptions were in

the group studied by Fryz 2 in which girls had

higher mean skeletal ages than boys throughout

the 6-11 year age-range and in the group studied

byJohnston,20 in which boys had higher mean

skeletal ages than girls at all ages 6-11 years.

While the present national study does not

provide reliable skeletal maturity data showing

differentials by specific ancestry among white

children in the United States, available information on white children in this country whose

parents were foreign born or of foreign ancestry

and on child populations from countries that

have contributed substantially by emigration to

the United States population are described

below insofar as they may provide some further

insight into variations in skeletal maturity

among white children in this country.

Only one previous study is available on the

skeletal maturity status of some white United

States children by more specific ancestry.

Toddz 4 reported insignificant differences in

maturity status between 315 Unit ed States

children both of whose parents were born in

Italy (usually southern Italy or Sicily) and 201

children both of whose white parents were born

in the United States.

Some information concerning skeletal maturity levels of groups of British, Danish, and

United States children is available from studies

of the differences between Greulich-Pyle6 and

Tanner-Whitehousezs assessments of the same

radiographs by Fry, 22 Ander-en,26 Asiel,27

Roche et al.28 and Blanco et al.z 9 The data are

summarized in table C. No matter what the

group of radiographs, if they are assessed by

both methods, the two sets of recorded skeletal

ages provide data about the relative level of

maturity in British (Tanner-Whitehouse) and

United States (Greulich-Pyle) children. Such

comparisons are indirect but valid except that

they are limited by the unrepresentative nature

of the samples on which these two methods are

based. It is important to note that the TannerWhitehouse standardizing sample consisted of

1,826 children in southwestern Scotland who

were examined cross-sectionally, 387 English

children studied longitudinally, and 351 English

children studied cross-sectionally. All reported

comparisons show higher mean values for

Tanner-Whitehouse skeletal ages than for

Greulich-P yle skeletal ages. Theoretically, these

differences could be due to differential weighting of bone-specific skeletal ages between the

two methods, but it has been shown that this is

not an important factor.z 8 There is no doubt

that the reported differences almost entirely

reflect variations between the standardizing

samples used by Greulich and PyleG and by

Tanner et al.zs Consequently, they can be

interpreted as showing the differences in skeletal

maturity status between a group of children in

Cleveland and a group of children in southwestern Scotland and England. The sample of

Fry2 z has been described earlier.1 Andersenz6

reported cross-sectional data from Copenhagen

10
Table C. Mean differences (years) between Greulich-Pyle and Tanner-Whitehouse assessments of the same radiographs

Sex and chronological age

Boys —

6. Oyears . . . . . . . . . . . . . . . . . . . . . . . . . . .

7.0years . . . . .. m. . . . . . . . . . . . . . . . . . . .

8. Oyeers . . . . . . . . . . . . . . . . . . . . . . . . . . .

9.0years . . . . . . . . . . . . . . . . . . . . . . . . . . .

10.Oyears, . . . . . . . . . . . . . . . . . . . . . . . . .

ll.Oyears . . . . . . . . . . . . . . . . . . . . . . . . . .

Girls

6,0years . . . . . . . . . . . . . . . . . . . . . . . . .

7.0years . . . . . . . . . . . . . . . . . . . . . . . . . . .

8.0years . . . . . . . . . . . . . . . . . . . . . . . . . . .

9.0years . . . . . . . . . . . . . . . . . . . . . . . . . . .

10.Oyears . . . . . . . . . . . . . . . . . . . . . . . . . .

ll.Oyears, . . . . . . . . . . . . . . . . . . . . . . . . .

American-Nabraska

(Fry, 1966)22

–1.0

–1.3

–7.4

–1.4

–1 .4

-1.0

–0.8

–1.1

–1.4

–1.3

–1.0

–0.7

children with a wide range of socioeconomic

levels. The number ofchildren varied from 43to

68 for each annual interval in each sex. The

analysis by Roche et al.28 was based on mixed

longitudinal data from 62 boys and82 girlsof

British ancestry who were born in Melbourne,

Australia, where they were living atthe timeof

the study. The differences reported by Fry**

and Roche et al.*8 are similar until ages 9-11

years in boysand 9-10 years ingirls when those

reported by Fry are greater. Those reportedly

Andersen*6 are less at allages except 8 yearsin

boys and 9-11 years in girls. Generalizing, these

studies indicate that the standardizing sample of

Tanner et aL* 5 was about 0.6 to 1.1 years

behind the Greulich-Pyle sample in mean skeletal maturity level. The radiographs were assigned

the same levels in “skeletal age years” when used

as standardizing samples. However, when the

two sets of standards are both applied to other

groups, ratings by the Tanner-Whitehouse

method tend to be greater than the corresponding ratings by the Greulich-P yle method.

The mixed longitudinal data of Roche3 O were

from essentially the same sample as that studied

by Roche et al.z 8 The mean Greulich-Pyle

skeletal ages in these Australian children of

British ancestry were very close to the mean

chronological ages (table D). This finding that

children of British ancestry born and living in

Australia mature more rapidly than children in

Danish-Copenhagen

(Andersen, 1968)2’

Mean difference

–0.4

–1.1

–0.6

–0.4

–0.3

-0.4

–0.9

–0.9

–0.7

–0.7

Australian-British ancestry

(Roche et al., 1971)’6

–1.2

–1.3

–1.2

–1.0

–0.7

–0.5

–1.1

-1.1

–1.1

–0.8

–0.6

–0.7

Table D. Modal differences between skeletal age and chronological age (Greulich-Pyle SA – CA in years) in “European”

children

Sex and

chronological age

80YS

6.0 years . . . . .

7.0 years . . . . .

8.0 years . . . . .

9.0 years . . . . .

10.0 years . . . .

11. Oyears . . . .

QirlJ

6.0 years . . . . .

7.0 years . . . . .

8.0 years . . . . .

9.0 years . . . . .

10.0 years . . . .

11. Oyears . . . .

Australian-British

Danish-Copenhagen

ancestry

(Roche, 1967)30

(Andersen, 1868)’s

Modal difference (years)

0.0

0.0

+0.2

+0.2

+0.3

+0.2

–0.1

–0.2

0.0

0.0

0.0

–o. 1

-.

–0.6

–0.9

–0.5

–0.4

–0.5

-.

–0.4

–0.6

–1.0

–0.5

–0.6

southwestern Scotland and England included in

the standardizing sample of Tanner et al., could

be due to the combined effects of several of the

factors mentioned earlier (i.e., genes, nutrition,

illness, and climate).

Kopczynska31 reported cross-sectional data

from 12,000 Polish children aged 7 to 16 years

in Warsaw. The mean skeletal ages (GreulichPyle) tended to be less than the mean chrono11
logical ages except that the differences were

small in girls aged 7-10 years. At later ages the

mean skeletal ages exceeded the corresponding

chronological ages. Rudzinski32 reported mixed

longitudinal data from 186 Polish boys aged 9.5

to 10.5 years and from 452 Polish boys aged

10.5 to 11.5 years. The mean Greulich-Pyle

skeletal ages were less than the corresponding

chronological ages, but the differences were only

about 0.3 year.

For the Copenhagen children studied by

Andersen,z 6 all group means were below the

Greulich-Pyle levels by about 0.4 to 1.0 skeletal

age years (table D). There was little change in

mem level with age and little difference between

the sexes.

In middle socioeconomic class Mexican children, Chdvez et al.33 reported that the mean

skeletal age (Greulich-Pyle) was only slightly less

than the mean chronological age, except in boys

at about 7 years. These data provide some

indication of the level of skeletal maturity to be

expected in the comparable socioeconomic class

of United States children of Mexican ancestry.

(In the present study Mexican children are

classified as white unless generally accepted as

American Indian or of another race–see appendix II.)

Other studies (white-Negro). –In partial contrast to the national findings reported here

which show that white children (boys and girls)

tend to be less advanced in skeletal maturation

than Negro children, Todd,z 4 using crosssectional radiographs of 149 Negro children,

tentatively concluded that there were no modal

differences in skeletal maturity level between

white and Negro boys but he did find that Negro

girls tended to be more advanced than white

girls. Sproul and Peritz34 reported mean skeletal

ages, standardized to a chronological age of 6.5

years, for 102 upper-middle-class Negro children

living in the San Francisco area. The chronological age of these children ranged from less

than 5 to more than 9 years, and they were the

5 percent of the sample closest to the median

stature for their age-sex specific groups. The

mean differences between the Greulich-Pyle

skeletal age and chronological age were very

small.

Malina3s’38 made Tanner-Whltehouse assessments of middle to upper-middle socioeconomic

class white children (N = 285) and lower to

lower-middle socioeconomic class Negro children (N = 367) in Philadelphia aged 6 to 11

years. Both the white and Negro children were

slightly in advance of the Tanner-Whitehouse

standards except at a few ages where the sample

sizes were small. The differences between the

means for the two groups were small, with the

Negro children showing a slight tendency to be

advanced despite their lower socioeconomic

status (table E).

Marshall et aL39 reported cross-sectional data

from 269 rural Jamaican children aged 7 to 11

years living about 15 miles north of Kingston.

The mean differences between TannerWhitehouse skeletal ages and chronological ages

(table F) were small except at 7.5 years, where

the mean skeletal ages were advanced over the

mean chronological ages in both the boys and

the girls. These rural Jamaican children were

retarded skeletally in comparison with those

Negro children in Philadelphia studied by

Malina.3s’s T

Other studies (other races). – While the number of children of other races (American Indian,

Japanese, Chinese, and others not classified for

census purposes as either white or Negro) in the

United States, and hence in the sample used for

Table E. Mean differences in skeletal age (Tanner-Whitehouse,

in years) between white and Negro children in Philadelphia

(Malina, 1969)s6

1

Sex and approximate mean I

White-Negro difference

chronological age

BOYS

6.2 years . . . . . . . . . . . . . . . .

7.0years . . . . . . . . . . . . . . . .

8.0years . . . . . . . . . . . . . . . .

9.0years . . . . . . . . . . . . . . . .

10. Oyears . . . . . . . . . . . . . . .

10.9years . . . . . . . . . . . . . . .

G&s

6.3 years . . . . . . . . . . . . . . . .

7.0years . . . . . . . . . . . . . . . .

8.0years . . . . . . . . . . . . . . . .

9.0years . . . . . . . . . . . . . . . .

10. Oyears . . . . . . . . . . . . . . .

ll.O years . . . . . . . . . . . . . . .

–0.4

-0.4

–0. 1

–0.2

+0. 1

0.0

+0. 1

–0.3

+(J.2

–0.4

–o. 5

–0.7

12
Tabla F. Modal differences between skeletal age and chronological age (Tanner-Whitahouse SA – CA in years) in Negro

children living abroad

Sex and approximate Rural Jamaica

chronological age (Marshall et al., 1970)3’

~s

7.5 years . . . . . . . . . . . . . . .

8.5years . . . . . . . . . . . . . . .

9,5vears . . . . . . . . . . . . . . .

10.5yaars . . . . . . . . . . . . . .

GM

7.5years . . . . . . . . . . . . . . .

8.5years, . . . . . . . . . . . . . .

9.5years . . . . . .. . . . . . . . . .

10.5 vaars . . . . . . . . . . . . . .

+0. 7

–o. 1

-0.1

–0.4

+1.1

+0. 5

+0. 2

+0. 1

the present study was too small to provide

reliable national estimates of their skeletal

maturity, available information from previous

studies on this aspect of development is included

here for comparative purposes.

Sproul and Peritzs 4 reported cross-sectional

data ) from 162 upper-middle-class California

children of Chinese ancestry. A hand-wrist skeletal age for each child was obtained by weighting the individual bone-specific skeletal ages by

their first principal components. These area

skeletal ages were standardized to a chronological age of 6.5 years after excluding lateappearing centers. The mean differences between the skeletal and chronological ages were

0.3 year in boys and zero in girls.

Cross-sectional data from 3,932 southern

Chinese children in Hong Kong who were born

between 1950 and 1956 (were 6-11 years of age)

have been reported by Low et al.40 (table G).

These Greulich-Pyle assessments reported by

Low et al. suggest a tendency to retardation that

was more marked in boys than girls and tended

to decrease with age in girls but not boys. These

variations from standard atlas rates may reflect

genetic differences between the samples of Low

et al.40 and Greulich and PyleG in age-associated

rates of skeletal maturation. Comparisons between the reports of Sproul and Peritz34 and

that of Low et al. for children of Chinese

ancestry living in the United States and Hong

Kong may suggest the extent to which environTable G. Modal skeletal age levels (Greulich-Pyle SA – CA in

years) at various chronological agas in American children of

Chinese ancestry and Chinese children

Sex and

approximate

chronological

Chinese ancestryCalifornia

(Sproul and Peritz,

age I

1971)34 I

Southern Chinese

(Low et al., 1864)40

8 OyS

6.0 years . . . .

6.5 years . . . .

7.0 years . . . .

8.0 years . . . .

9. Oyears . . . .

10.0 years . . .

11. Oyears . . .

Girls —

6. Oyears . . . .

6.5years . . . .

7. Oyears . . . .

8.0 years . . . .

9.0 years . . . .

10.0 years . . .

11. Oyears . . .

Modal skeletal age

-.

–0.3

--

--

-.

-.

-.

--

0.0

--

...

---

--

-.

–1.1

-..

–1.4

–1.5

–1.5

–1 .3

–1.2

–0.8

-.

–1.0

–1.1

–0.8

–0.6

–0.4

ment can influence the rate of skeletal maturation.

Data have been reported from California

children of Japanese ancestry and Japanese

children in Japan. Greulich41 reported crosssectiomd data from a “representative sample” of

American-born children of Japanese ancestry

living in the San Francisco area of California.

This sample included 13 to 48 children of each

sex at each annual interval who had been born

between 1945 and 1952. The mean GreulichPyle4 z skeletal ages were very close to the mean

chronological ages. Cross-sectional data from 63

Japanese children of above-average socioeconomic status living in California have been

reported by Sproul and Peritz.34 After standardization to a chronological age of 6.5 years, mean

skeletal ages were very close to the mean

chronological ages in each sex. Sutow43 reported cross-sectional data from normal Japanese children in Hiroshima who were born

between 1940 and 1946 and examined within 1

month of a birthday. The sample size varied

from 56 to 107 for each sex at each age.

Standards were selected from these radiographs

by a procedure similar to that used by Greulich

13
and Pyle and these standards were assessed

against the Greulich-Pyle Atlas in the manner

described by Sutow and Ohwada.44 These assessments show that, by comparison with the

Greulich-Pyle standards, the “median” levels of

skeletal maturity were low in these children, but

there was no systematic sex difference nor

change with increasing age in the amount of thk

retardation (tabIe H). The skeletaI maturity

standards of Sugiura and Nakazawa45 indicate

that Japanese children, especially boys, are

retarded skeletally by comparison with GreulichPyIe standards. As suggested by Greulich,41 it is

reasonable to conclude that the differences

between the skeletal maturity levels of children

of Japanese ancestry in California and those in

Japan are likely to be environmentally determined, although the possibility of selective

migration cannot be excluded. The same pertains to the Chinese data that were described

previously. Evidence that genetic factors may be

involved in the differences between mean skeletal maturity levels of Japanese children and

those of groups of white children in the United

States has been provided by Kimura4G347 who

reported that skeletal age was more advanced in

Japanese Americans 6-11 years old than in a

control group of native Japanese children.

Other studies (variability). –Consideration of

the magnitude of the standard deviations of the

skeletal ages of white and Negro children in the

6-11 year age range in the present national

study, within chronological age groups, and

those from previous studies reviewed in earlier

sections of this report provides some further

insight into the comparability of the findings.

Neverthelessj the national estimates of variability for all United States children from the

present study for which radiographs were taken

throughout the year (and not limited to ages

Table H. Modal skeletal age levels (Graulich-Pyle 5A - CA, in years) at various chronological ages in American childran of Japanesa

Sex and

chronological age

Boys

6.0 years. . .

6.5 years. . .

7.0 years, . .

7.5 years. . .

8.0 years. . .

8.5 yaars. . .

9.0 years. . .

9.5 years. . .

10.0 years. .

10.5 years. .

11.0 years. .

Girls —

6.0 years. . .

6.5.years. . .

7.0 years. . .

7.5 years. . .

8.0 years. . .

8.5 years. . .

9.0 years. . .

9.5 years. . .

10.0 years. .

10.5 years. .

11.0 yaars. .

14

ancestry and in Japanese children

Japanasa ancestry-California Japanese-H iroshima Japanase-Japan

[Greulich, 1957)4’ (Sproul and Peritz, 1971 )s4 (Sutow and Ohwada, 1953)44 (Suguira and Nakazawa, 1968)4 5

–0.6

-.

–0.4

...

–0.7

--

–0.4

--

–0.2

...

–0.4

+0.3

-.

–0.1

...

–0.1

-.

+0. I

. ..

+0. I

...

+0.6

...

–0.3

...

-.

...

...

---

---

...

...

...

---

+0.2

...

...

...

..-

---

...

..-

...

-.-

Modal skeletal age

–1.5

-.

–1 .7

—

-1.0

-.

–1.2

.-

–1.3

-.

–2.0

–1,7

-.

–0.7

--

–1.2

-.

–1.3

--

–1 .0

-.

-1.0

...

2.0

-.

2,0

-.

1.5

-..

1.5

-.

1.25

-.

...

0.75

...

1.0

. .

1.26

--

1.25

-.

0.5

-.
near birthdays as in most of the previous

studies) are generally within the range of variability reported in these previous studies and

usually near the upper end of the distribution, as

might be expected with the greater number of

assessors in the national study and the fact that

radiographs were taken throughout the year.

The slightly larger standard deviations reported

for Nebraska children by Fry22 and for Philadelphia children by Malina37 could reflect the

fact that these radiographs were not taken

systematically close to birthdays (table J). However, despite similar scheduling, those reported

for Philadelphia children by Johnston20 are

generally smaller. The smaller standard deviations at most ages reported for Cleveland children by Simmons,l 7 for Denver children by

Hansman andMaresh,48 and for Boston children

by Bayleyl 9 presumably reflect the socioeconomic and ethnic homogeneity of their

samples in addition to the scheduling of examinations close to birthdays. The reported data do

not show sex-associated differences in the variability of skeletal age within chronological age

groups.

Data from children outside the United States

have shown that variability was comparatively

low in the sample of Australian children of

British ancestry studied by Roche,30 but high

among the sample of Danish children studied by

Andersen2 G and the sample of Chinese children

studied by Low et al.40 (table K). Again, these

differences could reflect variations between the

studies in the scheduling of examinations.

Kopczynska31 reported standard deviations for

skeletal ages in Polish children that were at

about the center of the range of deviations

reported in the previous studies among selected

groups of United States white children. The data

of Marshall et al.s g shows a tendency to greater

variability in Negro Jamaican boys than among

Negro boys in the United States from the

present study;. there was no corresponding

tendency for girls.

Geographic Region

The mean regional

with few exceptions,

differences in maturation,

tend to be small enough to

be attributabl~ to chance alone with the siz~ and

design of the sample used in the 1963-65 Health

Examination Survey for these national estimates

(i.e., they do not exceed the 95-percent confidence limits for such estimates). Boys 6-11

years of chronological age in the Northeast and

Table J. Standard deviations (in yaars) for skeletal age within chronological age groups for studies among U.S. children

Sex and chronological age

Boys

6years .,.,.,

7years . . . . . .

8years .,,,..

9years ..,...

10years. , , ., ,

11 years. . , . . .

Girls

6years . . . . . .

7years. ,.. m.

8years . . . . . .

9 years . . . . . .

10years. . . . . .

11 years. . . , . .

Chicago

(Flory,

1936)’6

1.09

1.24

1.08

1.07

0.99

1.02

0.87

0.83

1.10

0.87

0.82

0.93

Cleveland

(Simmons,

1944)1 7

0.76

0.74

0.76

0.75

0.82

0.64

0.85

0.80

0.85

0.89

0.98

0.99

Denver

(Hansman Boston Philadelphia

‘Fry E

Nebraska

and (Bayley, (Johnston,

Maresh, 1962)] 9 1862)2” 1966)2 2

1961)4’ I

I 1

I White] Negro] White I Nagro

.-

...

0.8

...

-.

--

...

..-

0.9

...

--

-.

Standard deviation

0.78

0.84

0.90

0.92

0.95

0.87

0.75

0.69

0.73

0.78

0.90

1.03

-.

0.72

0.82

1.06

0.94

0.79

-.

0.73

0.64

1.00

0.12

1.13

0.74

0.80

1.06

1.32

1.45

1.20

0.91

1.21

1.02

0.90

1.24

0.87

1.2

1.0

1.0

1.2

1.1

1.2

1.0

1.2

0.9

1.0

0.7

0.9

1.4

1.5

1.4

1.2

1.3

1.4

1.2

1.3

1.3

1.0

1.2

0.9

0.96

0.96

1.00

0.95

0.85

1.09

0.89

0.88

0.87

1.04

1.22

1.00

0.90

1.08

0.64

0.88

0.86

1.14

0.96

0.85

1.03

1.33

1.24

1.18

15
Table K. Standard daviation (years) for skelatal age within chronological age groups for studies among children of foreign countries

Sex and chronological age

Boys

6.0years . . . . . . . . . . . . . . . .

7.0years . . . . . . . . . . . . . . . .

7.5years . . . . . . . . . . . . . . . .

8.0years . . . . . . . . . . . . . . . .

B.5years . . . . . . . . . . . . . . . .

9.0years . . . . . . . . . . . . . . . .

9.5years . . . . . . . . . . . . . . . .

10.Oyears . . . . . . . . . . . . . . .

10.5years . . . . . . . . . . . . . . .

ll.Oyears . . . . . . . . . . . . . . .

Girls

6.0years . . . . . . . . . . . . . . . .

7.0years . . . . . . . . . . . . . . . .

7.5years . . . . . . . . . . . . . . . .

8.0years . . . . . . . . . . . . . . . .

8.5years . . . . . . . . . . . . . . . .

9.0years . . . . . . . . . . . . . . . .

9.5years . . . . . . . . . . . . . . . .

10.Oyears . . . . . . . . . . . . . . .

10.5years . . . . . . . . . . . . . . .

ll.Oyaars . . . . . . . . . . . . . . .

Australian-British

ancestry

(Roche,1967)s0

0.5

0.5

-.

0.7

-.

0.8

-.

0.8

-.

0.8

0.5

0.6

-.

0,7

-.

0.6

.-

0.6

...

0.7

Danish

(Andersen, 1968)2’

I

Chinese Jamaican

(LowetaL,1964)40 (Marshall etal.,1970)3 9

Standard deviation

-..

0.9

-.

1.0

...

1.0

-.

1.4

-.

1.1

...

1.0

-.

0.8

-.

0.9

...

0.9

...

1.0

0.8

0.9

-.

1.1

-.

1.3

...

1.3

-.

1.2

0.9

1.0

-.

1.2

-.

1.3

-.

1.4

...

1.3

—

...

0.7

-.

1.7

-.

1.5

.-

1.3

...

-.

-.

1.1

---

1.2

.-

0.8

-.

0.9

-.

Midwest Regions of the United States generally ages 6-9 years than those inthe South and West.

tend to be more advanced in skeletal maturity

than boys in the South or West, while girls in

the West are less advanced skeletally than girlsin

the other three regions (table 2, figure9 ).

Among boys at individual years of chronological age, the mean skeletal ages (hand-wrist)

of those in the Northeast are more advanced

(closer to their chronological age) at chronological ages 6, 8, 10, and 11 years than for boys

in other areas of the country. At ages 7 and 9

years, boys from the Northeast lag slightly

behind those in the Midwest in this respect.

Only at 7 years for boys in the Midwest and

Northwest and at 11 years in the Northeast are

the mean regional differences large enough to be

considered statistically significant. Boys of

chronological ages 6, 7, and 11 years in the

South and those of ages 8-10 in the West tend to

be less mature skeletally than those from the

other regions of the country.

Girls in the Northeast and Midwest are, on the

average, more skeletally mature at chronological

H-owever~ only at age 6 for girls in the Northeast

and Midwest and at ages 7 and 9 years for those

in the Northeast are the mean skeletal ages

(hand-wrist) significantly higher (at the 5-

percent probability level) than those for girls in

other regions. Among older girls 10 and 11 years

of age at their last birthday, mean regional

differences in skeletal maturity are negligible.

When any effect of differences in age distribution for children 6-11 years of age among the

four regions of the country is removed by an

indirect age adjustment, both boys and girls in

the Northeast are clearly more advanced and

those in the Midwest slightly more advanced in

skeletal maturity than those from the West and

South (figure 10).

Girls tend to be more advanced in skeletal

maturity (female equivalent values) than boys in

each of the four regions of the country. The

mean differences are greatest by 3 to 5 months

(and large enough to be statistically significant

at the 5-percent probability level) among older

16
BOYS

5

0

( I I I I I I

6 7 8 9 10 11

CHRONOLOGICAL AGE IN YEARS

— Northeast . . . .. Midwest

GIRLS

t

(Female equivalents)

t

I t I I I I I

6 7 8 9 10 11

CHRONOLOGICAL AGE IN YEARS

.-. south . . . . West

Figure9. Mean difference in months between skeletal age (hand-wrist) and chronological age for boysand girls, by geographic region

andchronological age in years: United States, 1963-65.

ma

,

I

NORTHEAST MIDWEST SOUTH WEST

~aoys ~Gi,ls

Figure lO. Difference between actual and expected mean skeletal age (hand-wrist) for boys and girls 6-11 years of

chronological age, by geographic region: United States,

1963-65.

children aged 10 and 11 years in the Midwest,

South, and West; among 9-year-olds in the

Northeast; and among 6-year-olds in the Midwest. Few minor, nonsignificant exceptions did

occur—at chronological age 8 years in the

Northeast and South, 7 years in the Midwest,

and 6 years in the West—where the mean skeletal

ages (hand-wrist) of boys exceed those of girls,

on the average, by 2 months or less.

Among both boys and girls in each of the four

regions of the country, the greatest relative

variation in skeletal maturity, in relation to the

magnitude of the mean, is among the youngest

children 6 years of age. Older children, 10 years

of age among boys and 11 years of age among

girls, are consistently the least variable in this

aspect throughout the country. The relative

variability in skeletal maturity among boys in

each of the four regions decreases consistently

with increasing chronological age from 6 to 10

years of age, then increases slightly among

1l-year-oIds. In contrast, no consistent regionaI

pattern in relative variability by chronological

age is evident among girls, except at the extremes–6 and 11 years-as noted above. Relatively more variabilityy in skeletal maturity is

present among younger boys than among girls

6-8 years of chronological age in each region of

the country, and, among older boys than girls, at

chronological age 11, except for those in the

17
South. At chronological age 10 years, boys are

relatively less variable than girls in skeletal

maturity.

When only white children aged 6-11 years are

considered, the analysis by geographic regions

shows that boys in the South and West and girls

in the West tend to be somewhat less advanced

skeletally than children in other regions. The

regional pattern in skeletal development among

Negro children is similar to that for white

children, but the sample size is too small to

provide reliable estimates in this detail for that

segment of the population.

White children at each year of age across the

6-1I year range were generally less mature

skeletally than Negro children in each of the

four regions of the country (table 4). The

pattern is somewhat more consistent among girls

than boys. Only in the South (where the

proportion of Negro children was about twice

that in the other three regions at the time of this

study) among younger boys 6-8 years of chronological age are the differences large enough to be

considered statistically significant at the 5-

percent probability level.

When the effect of the differences in the age

distribution for white and Negro children in the

four regions of the country is removed, the

pattern of more advanced skeletal maturity than

expected among both white and Negro boys and

girls 6-11 years of age in the Northeast and

Midwest and less advanced than expected among

those in the South and West is clearly evident

(figure 11). However, because of the relatively

small size of the Negro population in the West,

particularly, and in the Northeast and Midwest,

the apparent white-Negro differences shown

here among the regions are not statistically

significant.

Other studies. –Only infrequently have geographic factors in relation to skeletal maturation

been studied previously in circumstances that

allow the separation of racial and socioeconomic

factors. The only possibly revelant data come

from previous uncoordinated studies of children

living in different regions at different points in

time. Sampling procedures differ among these

studies, and comparabilityy of the assessment

techniques employed is unknown. In fact, it is

possible that regional differences in this aspect

of development that are not due to local

variations in the incidence of illness, malnutrition, climate, or altitude may not exist. Geographic differences , within the United States

among the 6- to 1l-year-old children in this

national study, in the ‘prevalence of abnormal

findings on survey examination-whether due to

illness, malnutrition, or other causes—have been

reported previously. 49 The prevalence of physical abnormalities among these children is significantly less among those in the West than in the

other three regions of the country and slightly

but not significantly higher among those in the

Midwest than those in the Northeast or South.

However, skeletal maturity levels in the present

study are slightly higher among children in the

BOYS

5

GIRLS

o

–5

t , I ! , 1 t t I I 1 1 1 t I ! I 1 1 , 1 I 1 1

NORTHEAST MIDWEST SOUTH WEST NORTHEAST MIDWEST SOUTH WEST

Izami’e ❑“’””

Figure 11. Difference between actual and expected mean skeletal age (hand-wrist) for white and Negro boys and girls 6-11 years of

chronological age, by geographic region: United States, 1963-65.

18
Northeast and Midwest than in the West or

South.

If secular changes have occurred in the skeletal maturation rates of U.S. children, presumably they reflect changes in many factors,

including levels of nutrition and the incidence of

illness or disability. Dearborn and Rothney50

reported skeletal ages for 1,553 children aged 7

to 17 years (among whom 24 percent were of

Italian ancestry) who were assessed using the

1934 unpublished Todd standards. These children were born about 1916 and were living in

New England.51 The data indicate consistent

slight mean retardation of skeletal maturation

(0.4 to 0.9 years) in comparison with the

Greulich-Pyle standards, if it is assumed, as a

reasonable approximation, that the 1934 and

1937 Todd standards were equivalent in level.

These earlier findings are inconsistent with the

present findings from representative samples of

children in the Northeast.

The possible effects of climate are difficult to

evaluate. It has been suggested that a tropical

climate per se retards skeletal maturation,5ZY53

but convincing evidence is lacking. There is

doubt about the relevance of observations that

heat promotes calcification in vitro and in

chicken eggs.s4~ss Other studies of experimental animals have involved extreme environmental temperature differences.5 6‘59

Important observations have been made by

Nissen and Riesen,GO who kept three chimpanzees almost completely in the dark from birth to

ages ranging from 7 to 33 months. A fourth

animal was deprived of light from 8 to 24

months. There were no differences between

them and controls in either food intake or the

amount of body movement, but the onset of

ossification was delayed in the animals deprived

of light.

Others have analyzed data from children, but

there is a lack of agreement among these

investigators. Sawtell~ 1 in a study of 250

children found no tendency for the onset of

ossification of carpals to occur during any

particular season. However, in “normal” southwestern Ohio children aged 1-5 years, there

was a tendency for the onset of ossification to

occur between February and August rather than

in the remainder of the year,Gz and onset of

ossification was most common in the summer

and least common in the winter in the malnourished Florida children.63

In the present national study, the skeletal

maturation levels of children in the South and

West are slightly lower than for children from

the other two regions. However, while the

climate in the South is generally warmer, that in

the West covers the entire range of temperatures

in this country. Hence, neither illness, malnutrition, other recorded conditions, nor climate

seems to explain adequately the slight geographic differences in skeletal maturity levels of

U.S. children found in the present study. The

broad regions into which the United States had

been divided for administrative purposes are so

heterogeneous they may have obliterated local

variations in skeletal maturity levels.

Urban-Rural

In some countries, urban and rural populations are sharply contrasted socioeconomically

and, in some cases, genetically also. In such

circumstantes, there may be real urban-rural

differences in skeletal maturity levels.64-71

There were no consistent patterns of skeletal

maturity differences among children in this

national study that could be related to urbanrural factors or to the size of urban communities

(table 6).

Girls in both urban and rural areas of the

United States are generally more mature skeletally (female equivalent values) than boys of

chronological age 6-11 years. The sex differences

in mean skeletal age (hand-wrist) were largest—3

to 4 months—among the older children who

were 10 and 11 years of age at their last’

birthday. This implies a relative lack of differences between urban and rural areas of the

United States in the genetic and environmental

factors that influence the rate of skeletal

maturation.

Socioeconomic Factors

There was only a slight association between

socioeconomic status as measured by family

income and the level of skeletal maturity of

U.S. children as determined in the present

national study.

19
Among boys of chronological age 7 through 9

years, those most advanced in skeletal age

(hand-wrist) were from families in the highest

annual income level—$10,000 and more—while

the mean skeletal age vaIues were lowest among

those from families with annual income of less

than $5,000 (table 3 and figure 12). Among the

oldest boys (age 11 years at their last birthday),

those from the lowest income level tended to be

the most advanced in skeletal maturity, while

those from the middle income bracket were least

advanced in skeletal maturity. The differences

between these extreme mean values of skeletal

age–ranging from 0.2 months at 8 years to 3.6

months at 9 years-were too small to be of

statistical significance considering the size and

design of the sample used in the survey.

Girls aged 6-11 years from families in the

higher income levels of $5,000 or more per year

were slightly but consistently more advanced in

skeletal maturity than other girls. Only at ages

7-9 years were those in the lowest income

bracket (less than $5,000) the least advanced in

ences between the extreme mean values of

skeletal age were negligible (less than 1 month),

except at age 9 years when the girls from the

lowest income level families were significant Iy

more retarded (mean difference of 4 months) in

skeletal maturity than those from families with

income of $10,000 or more.

If children in families from the extremes of

the income range are considered–those in families with annual income less than $3,000 and

those of $15,000 or more–skeletal maturity is

consistently least advanced among those in the

lowest income bracket across the chronological

age range 6-11 years among both boys and girls

when all races are combined.

When the effect of differences in the age

distribution among the various income level

groups is removed, boys and girls of 6-11 years

in middle and upper income bracket families

are sIightly more advanced in skeletal maturity

than expected, and those at the lowest income

level are least advanced in this respect, though

the mean differences are insignificant (figthis aspect of development. However, all differ- ure 13).

:5

a

BOYS

6 7 8 9 10 11

CHRONOLOGICAL AGE IN YEARS

_ Less than $5,000 . . . . .

GIRLS

5

I

(Female equivalents]

o

-5

-lo

“5~6 7 8 9 10 11

CHRONOLOGICAL AGE IN YEARS

$5,000 – $9,999 . . . .. $10.000 or more

Figure 12. Mean difference in months between skeletal age (hand-wrist) and chronological age for boys and girls, by annual family

income and chronological age in years: United States, 1963-65.

20
BOYS GIRLS

5 5

am

~~

;g

gz

“~

~111

~w o

Iv7i

G< o

tcxkkr

Ea

<$

:j

-6 –5

,

Less than $5,000 $5,000-$9,999 $10,000 or mOre Less than $3,000 $15,000 Or more

ANNUAL FAMILY INCOME EaiilBO’s lEaGir’sANNUAL FAMILY INCOME

Figure 13. Difference between actual and expected mean skeletal age (hand-wrist) for boys andgirls 6-11 years of chronological age,

by annual family income: United States, 1963-65.

Boys tend to be consistently less advanced in

skeletal maturity than girls of corresponding

chronological age across all income levels, with

minor exceptions at chronological age 8. Only

among the oldest children, those 10 and 11

years of age, were the sex differences in mean

skeletal age (hand-wrist) within each income

level large enough (approximately 4 months or

more) to be statistically significant.

The pattern of variation in skeletal maturity

among boys and girls across the three income

levels is inconsistent also. Boys of chronological

ages 8 and 11 years are more variable in skeletal

maturity than girls of the same age in each of

the three income groups, but boys are less

variable at 9 and 10 years.

Among white boys and girls, there is evidence

of a positive association of skeletal maturity

with family income. Mean skeletal age (handwrist) increases slightly but consistently with the

income level of the family. No such consistent

pattern was present among Negro boys or girls.

When racial differences in skeletal maturity

among white and Negro children are considered

in relation to family income level, white children

aged 6-11 years consistently had lower mean

skeletal ages than Negro children of comparable

chronological age, with minor exceptions at 10

years for boys and 8 years f or girls among those

whose family income was less than $5,000.

Among children from families in the intermediate income brackets ($5 ,000-$9,999 per

year), white boys tended to be more advanced in

skeletal maturity than Negro boys at chronological ages 8-11, but younger white boys and

white girls of 6 and 8-10 years were less

advanced in this respect than their respective

Negro counterparts (table 5). These patterns are

clearly evident in figure 14 where the effect of

differences in the age distribution of the Negro

and white children within these income levels

has been removed. The number of Negro children in families with annual income of $10,000

or more at the time of this study was too small

to obtain reliable national estimates of skeletal

maturity for them.

Similar to the findings with respect to family

income, there is a lack of a consistent relationship between skeletal maturity of children and

the formal education of their fathers (head of

household). This is evident in table 7, and would

be expected because of the high level of association between income and education (r = .58) .68

Other studies. –Skeletal maturity levels of

children from different socioeconomic backgrounds have been reported for subgroups of the

population in the United States and other

countries. These previous findings will be considered in relation to those from the present

study.

Sproul and Peritz34 reported data from 162

California children of Chinese ancestry. These

children were above average socioeconomically

for the San Francisco area and, presumably,

would be for Hong Kong also. Low et al.40

reported Greulich-P yle skeletal ages from a large

21
BOYS

5

GIRLS

5

a%

Wb &z

~o

Lz

g~

mu

::

0

- 0

z-!

~<

<b

a-l

b?6(/3

-5 -5

, 1 , t 1 r 1 1 1 1 I t 1 11 I I 1 I I I 1 I I

Less than $5,000 $5,000 – $9,999 $10,000 or more Less than $5,OOO $5,000-$9,999 $10,000 or more

ANNUAL FAMILY INCOME

I%zlwhi’e ❑ NegrO

ANNUAL FAMILY INCOME

Figure 14. Difference between actual and expected mean skeletal age (hand-wrist) for white and Negro boys and girls 6-11 yaars of

chronological age, byannual family income: United States, 1963-65.

sample of 3,932 Hong Kong children who were groups of Hong Kong children cannot be exgrouped into high, middle, and low socio- cluded with certainty but are not considered to

economic groups (table L). This grouping was have been an important factor.” In contrast to

made using a combination of parent’s education, the findings from the present national study

parent’s occupation, total family income, and where essentially an association was not found

housing.6g Population genetic differences be- between skeletal maturity of children and the

tween the California children and the three

“Lee, personal communication, 1972.

Table L. Mean skelatal ages (in years) for children of Chinese ancestry at various socioeconomic levels

Chinese ancestryCalifornia

Southarn Chinese in Hong Kong

Sex and chronological age (Sproul and Paritz, 1971 )34 (Low et al., 1964)40

,

Very high status High status Middle status Low status

Total number of children 162 768 1,050 2,114

8oys

6. Oyears . . . . . . . . . . . . . . . . . . . . . . . . . . .

6.5years . . . . . . . . . . . . . . . . . . . . . . . . . . .

7. Oyears . . . . . . . . . . . . . . . . . . . . . . . . . . .

8. Oyears, . . . . . . . . . . . . . . . . . . . . . . . . . .

9. Oyears . . . . . . . . . . . . . . . . . . . . . . . . . . .

10. Oyears . . . . . . . . . . . . . . . . . . . . . . . . . .

11. Oyears . . . . . . . . . . . . . . . . . . . . . . . . . .

Girls

6. Oyears . . . . . . . . . . . . . . . . . . . . . . . . . . .

6.5years . . . . . . . . . . . . . . . . . . . . . . . . . . .

7. Oyears . . . . . . . . . . . . . . . . . . . . . . . . . . .

8. Oyears . . . . . . . . . . . . . . . . . . . . . . . . . . .

9. Oyears . . . . . . . . . . . . . . . . . . . . . . . . . . .

10. Oyears . . . . . . . . . . . . . . . . . . . . . . . . . .

11. Oyears . . . . . . . . . . . . . . . . . . . . . . . . . .

-.

6.2

.-

...

-.

.-

.-.

--

6.5

...

...

.-

.-

.-.

Mean skeletal age

5.4

-.

5.8

6.7

8.0

9.2

10.5

5.8

. .

6.2

7.4

9.1

9.7

11.3

5.0

-.

5.7

6.6

7.6

8.8

9.8

5.4

-.

6.0

7.2

8.3

10.0

11.0

5.1

-.

5,6

6.3

7.4

8.4

9.6

5,3

.-.

5.8

6.5

7.9

9.2

10,4

22
single socioeconomic fact or of family income,

the skeletal maturity level among these Chinese

children was generally more advanced among

those of high, as opposed to low, socioeconomic

status. However, the latter mean differences are

small despite the large range of socioeconomic

status between the groups compared. These

comparatively small differences are in a~eement

with the observations of Grande Coviah and Rof

Carballo.70

Kopczynskas 1 reported data from upper and

lower socioeconomic class Polish children (total

N= 280) that showed a positive association

between socioeconomic status and the level of

skeletal maturity. These findings are in agreement with those of DeWijn7 1 for Dutch children. Andersenz G reported a marked association

of occupation of father, and a lesser association

of family income with skeletal maturity level. In

her data, crowding of apartments was associated

with skeletal retardation in the lower but not

the upper socioeconomic groups. Andersen presented her findings as the percentages skeletalIy

advanced or retarded but did not report the

differences in skeletal age years. Consequently,

more precise comparisons cannot be made with

these data.

Comparisons between boys aged 6.5 to 8.5

years of very low (N = 80) or high (N = 20)

socioeconomic status in a suburb of Tunis show

a median difference in skeletal maturity

(Greulich-Pyle) between the two groups of

approximately 1 year as reported by Young et

al.7 z These findings are in agreement with those

of Rea73 for Nigerian preschool children. However, Neyzi et al.,74 using data from 3,000

urban Turkish children of moderately different

socioeconomic levels, found only slight associations with skeletal maturity levels.

Acheson and Hewitt75 related socioeconomic

status based on father’s occupation to skeletal

maturity in preschool English children. There

was a slight tendency for skeletal maturity to be

more advanced in boys of upper socioeconomic

status (about O.2 year) but no such tendency in

the girls.

Asielz 7 reported only a slight socioeconomic

influence on the level of skeletal maturity in

Belgian boys aged 5 to 9 years, whether assessments were made by the Greulich-Pyle or the

Tanner-Whitehouse method.

BONE-SPECIFIC SKELETAL AGE

FINDINGS

In the Greulich-Pyle method of assessment,

the skeletal maturity of the hand-wrist assigned

to an individual child is based usually on the

average of the ages assigned those of his 31

hand-wrist bones that are radio-opaque but not

classified as adult. Some investigators use the

median; others assign an age to the whole area

without recordihg separate skeletal ages. In this

report, as in the previous one,l the common

practice of using the average has been followed.

The order of onset of maturation and the rate of

maturation of individual bones vary considerably among individual children. For children in

the age range of concern in this study, 6-11

years, the majority of the 31 hand-wrist bones

have become radio-opaque, but their maturation

is not complete. There are only six bones in

which ossification is normally delayed until age

6 years or later. During the age range 6-11 years,

ossification begins typically in the distal ulnar

epiphysis, trapezium, trapezoid, and adductor

sesamoid in boys and in the pisif orm in each sex.

Ossification of the flexor sesamoid is usually

delayed until the twelfth year or later.

Race

White children in this country generally tend

to be less advanced than Negro children in the

skeletal maturity of the individual hand-wrist

bones, though the pattern is not as consistent as

that for overall skeletal age (hand-wrist).

For three-fifths (19) of the 31 bones, the

mean skeletal age of white children lags consistently behind that for Negro children of corresponding chronological age, with only minor

exceptions (table 9). This pattern (mean differences of 2-4 months, which are statistically

significant at the 5-percent probability y level) is

generally consistent for both boys and girls

across the 6-11 year age range for seven of the

bones–the hamate, lunate, trapezium, metacarpal I, and metacarpal III-V. For seven other

bones–the radius, ulna, capitate, triquetral,

scaphoid, trapezoid, and metacarpal II-the only

exception to this pattern is among 10-year-old

boys. For children of chronological ages 6-11

years, the mean white-Negro differences in

23
skeletal age of these seven bones are also large

enough to be statistically significant (differences

of 2-4 months) except for the ulna among boys.

The mean skeletal age for the adductor sesamoid

also is significantly more advanced among Negro

than white boys and girls, as are the mean

skeletal ages for the distal phalanges III-V among

boys, but the patterns at separate years of

chronological age are less consistent than for the

14 bones described previously. For the proximal

phalanx I among both boys and girls and the

distal phalanges III-V among girls, the mean

racial differences are negligible (not significant

at the 5-percent probabilityy) and are less consistent over the age range in this study.

The racial differentials in mean skeletaI maturity levels are less consistent in the remaining

12 bones. Proximal phalanges II-V and the

middle phalanx II were slightly more advanced

in skeletal maturity among white than Negro

children, but this pattern was not consistent

across the age range for either sex. The pattern

of racial differences in skeletal maturity is even

less consistent with respect to the middle phalanges III-V and the distal phalanx I, and differs

between boys and girls. These latter four bones

were slightly but not significantly more mature

among white than Negro girls. Among white and

Negro boys, the mean skeIetal ages of the middle

phalanges III-V were identical for all ages combined, while in the distal phalanx I, white boys

lagged slightly behind Negro boys in skeletal age,

on the average. In the later ossifying pisiform

and flexor sesamoid, white boys are slightly

more skeletally mature than Negro boys, but

this racial pattern is reversed among girk. The

mean skeletal age for the distal phalanx II was

identical for white and NeWo girls, while white

boys were somewhat less mature than Negro

boys with respect t~this bone.

If Todd’sl 8 theory of the evenly maturing skeleton were applicable, one would expect mean

skeletal ages (hand-wrist) to be fairly evenly

distributed across the 31 individual bones in

white and Negro children. The extent of lack of

agreement with this theory among the 6- to

1l-year-old United States children is clearly

evident in figure 15, which shows, for the total

chronological age range (6- 11 years), the mean

differences between skeletal age and chronological age for white and Negro boys and girls

for 28 of the individual bones. The pisiform and

the two sesarnoids have been omitted because

they are ossified only in the more mature children.

Geographic Region

The regional pattern found among United

States children 6-11 years of chronological age

in the present national study (i.e., somewhat

more advanced skeletal age (hand-wrist) among

those children in the Northeast and Midwest

than those in the South and West) is evident also

in the mean skeletal age values for 30 of the 31

hand-wrist bones (table 10). The only exception

is for the adductor sesamoid, where the children

from the West and South are slightly, but not

significantly, more advanced than those from

the Midwest.

Income

Among both boys and girls, those from the

lower income level families (with annual income

of less than $5,000) tended to be somewhat less

advanced in the skeletal maturity of individual

hand-wrist bones than those from the higher

income level families (with annual income of

$7,000 or more). This is similar to the findings

with respect to their skeletal age (hand-wrist).

The mean skeletal age findings for six of the

individual hand-wrist bones (representative of

the groups of principal maturation patterns

shown for all but the later ossifying bones) “

among these children are shown by the income

level of their families in tables 11 and M.

Skeletal age for these typical bones tends to be

more advanced (or less retarded) relative to

chronological age among children in the higher

than lower income level families. This effect was

present in each sex and was somewhat more

marked and consistent in the third and fourth

proximal phalanges and the fifth middle phalanx, indicating that the maturation of these

bones might be particularly sensitive to environmental influences.

Other studies. –Bone-specific skeletal age findings by race or ethnic background from some

previous studies among groups of children in the

United States and other countries are available

for comparison with the present findings for

United States children.

24
Negro boys

4.* . / ●+-=9..,.**” .*

. . . . . . . . . . . ...” ---”

.*’**.** .+ . . . . . . . . . . . . . . . . . ●.* ●** % .“ ●.=””

““*.Z

White bow

~$x #’x f ● ●*X

Negro girls

t:.h +~%

~ .“ .,------ t:”.h#. , i

,Z--zzz.

. ..“+&- ~..- ,

.“ “..

%J.” “.**●.”●. >& N m- m--* -y&.: .........”.4 q-d................

.“ .............. “..”.“.. .. ---Z* .

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

......

k

White girls

–20 r

Figure 15. Mean white-Negro differences in the deviation of bone-specific skeletal agesof chronological agesof boys and girls: United

States, 1963-65.

Table M. Mean differences betwaen skeletal and chronological ages in years among income groups.

Sex and bone

Bovs

Triquetral . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Metacarpal ill . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Metacarpal V . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Proximal phalanx ill . . . . . . . . . . . . . . . . . . . . . . . .

Proximal phalanx lo . . . . . . . . . . . . . . . . . . . . . . . .

Middle V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Girls

Triquetral . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Metacarpal ill . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Metacarpal V..........,.. . . . . . . . . . . . . . . . .

Proximal phalanx ill .,..,... . . . . . . . . . . . . . . . .

Proximal phalanx lo . . . . . . . . . . . . . . . . . . . . . . . .

MiddleV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Income

Lassthan $3,000- $5,000- $7,000- $1o,ooo- $15,000

$3,000 $4,999 $6,999 $9,999 $14,999 or more

Mean difference

–0.6

–1.0

–1.2

–2.4

–2.5

–2.2

–o. 1

–0.5

–0.4

–1.2

–1.3

–1 .4

——

0.9

0.6

0.7

–0.2

–0.2

0.2

–0.5

–0.3

–0.3

–1.1

–1.0

–1 .3

0.7

0.7

0.6

0.7

0.7

0.9

–0.5

–0.4

–0.5

–0.6

–0.5

–0.7

–0.8

–o. 1

0.1

1.1

1.0

0.9

0.8

1.0

1.2

2.2

2.2

2.6

0.1

–0.2

–0.4

0.6

0.8

–0.2

–0.6

–0.6

–0.6

0.1

0.1

–0.2

0.5

0.1

0.3

1.2

1.4

0.1

2.1

3.0

2.8

2.6

2.6

4.0

25
Roche7 reported bone-specific skeletal ages

for 4-year-old children of British ancestry living

in Melbourne, Australia. There was a definite

tendency in the boys and a slight tendency in

the girls for the rays of the hand to be less

mature as those progressively closer to the ulnar

side were considered. (A ray of the hand-wrist

consists of a metacarpal with its associated

phalanges, e.g., metacarpal III, proximal phalanx

III, middle phalanx III, and distal phalanx III.)

These variations could have been due to real

differences in these children, limitations in the

standardization group used to construct the

Greulich-Pyle standards, or errors made during

assessment.

Malina36>76 reported Tanner-Whitehouse

skeletal age scores for specific bones in white

and Negro Philadelphia children aged 6 to 11

years. These individual bone scores cannot be

converted to skeletal ages, but they can be used

to compare the levels in white and Negro

children of the same sex. The radius and ulna

were more advanced in the Negro boys than in

the white boys at almost all ages and, in general,

the carpals were more advanced at ages 6 to 9

years. At most ages, however, the proximal

phalanges were less advanced in the Negro boys

than the white boys. Almost all bones tended to

be more advanced in the Negro girls than in the

white girls except the ulna at younger ages.

Peritz and Sproul,77 using the racial samples

described earlier,~ 4 reported mean skeletal ages

(Greulich-Pyle) for the triquetral, lunate, proximal phalanx III, and distal phalanx III, aft er

each had been standardized to a chronological

age of 6.5 years (table N). In the boys, the

proximal phalanx III or distal phalanx III tended

to be the most mature of these bones; and in

each group of girls, the triquetral tended to be

the most mature. Some differences between

mean skeletal ages were considerable, possibly

due to the small number in the groups studied;

e.g., in the Japanese boys the difference between

the mean ages for the lunate and proximal

phalanx III was 1.4 years.

Range of Bone-Specific Skeletal Ages

Many previous studies reported in the literature claim that illness or malnutrition has

differential effects between bones on ages at

Table N. Mean skeletal ages for selected bones, standardized to

a chronological age of 6.5 years (Sproul and Peritz, 1971)34

Sex and race

Boys

White . . . . . .

Negro . . . . . .

Chinese . . . . .

Japanese . . . .

Girls

White . . . . . .

Negro . . . . . .

Chinese . . . . .

Japanese . . . .

Bone

EEIEIE

Mean skeletal age

6.5

6.7

5.9

6.3

6.8

7.3

6.7

7.0

5.9

6.2

5.6

5.4

6.1

6.5

6.2

6.1

6.9

6.7

6.4

6.8

6.5

6.0

6.3

6.9

6.6

6.9

6.5

6.2

6.4

6.4

6.1

6.5

onset of ossification or rates of later maturation.

Findings from this present national survey with

respect to the consistency and variability in the

range of bone-specific skeletal ages across racial,

regional, and economic subgroups among the

United States children of chronological ages

6-11 years provides normative data that can be

used to further assess the effect of such factors

as illness or malnutrition on skeletal

development.

Race. –Medians and quartile points in the

distribution of the range from the highest to the

lowest bone-specific skeletal ages within the

hand-wrists of individual white and Negro boys

and girls by single years of chronological age

from 6-11 years are shown in table 12. The data

for each sex are based on male skeletal age

standards. In interpreting these data, it should

be recalled that some “bones” were not assessed

in these children because, as noted earlier,

skeletal age in years cannot be assigned to bones

that are not yet radio-opaque or to those bones

that have reached adult levels of maturity.

In both white and Negro boys, the median

ranges decrease consistently with advancing

chronological ages from 29 months among both

groups at age 6 years to 19 months among white

boys and 21 months among Negro boys at age

11 years. In contrast, for white and Negro girls,

the median range was greatest at age 6 (27

months for whit e girls, 28 for Negro girls) but

26
lowest at 8 and 9 years (about 22 months for

both groups) and increased slightly to 24

months for both groups at 10 and 11 years. In

general, there were corresponding trends at the

75th and 25th percentile levels. The greatest

variability (as measured by the interquartile

range P7s -P2s ) in the range of bone-specific

skeletal ages for white and Negro boys was

among the younger, 6-9 years of age, and the

least variability among the older boys, 10 and 11

years of chronological age. The sex differences

in both white and Negro children in the agerelated patterns of change in these ranges probably reflect the differential timing of pubescent

changes between sexes.

When the white and Negro groups were

compared, the differences between the median

ranges tended to be slightly greater among

younger white than Negro boys at ages 6-8 yem;

but lower at ages 9-11 years. Only at age 9 years

was the racial difference in median range among

boys substantial. In contrast, among girls, median ranges were slightly but consistently greater

among the Negro than white groups, with a

negligible exception at chronological age 9 years.

ReL@n.-No significant pattern of regional

differences in the median ranges for bonespecific skeletal ages was found among United

States boys or girls (table 13). Boys in the West

showed the highest median values at ages 6, 8,

and 9 years but the lowest at age 10 years.

Among girls of 8-11 years, median range values

were greatest for those in the Midwest, and at 6,

9, and 10 years were least for those in the West.

Other regional differences in these median

ranges were less inconsistent. Presumably, this

reflects the heterogeneity in the populations

included in the broad regional groupings into

which the country was divided for the purposes

of this national study.

The variability in the range values tended to

be greatest among younger boys (7 years of age

in the Midwest, South, and West and 8 years in

the Northeast) and least among older boys (10

years of age in the Northeast and West and 11

years in the Midwest and South). The regional

pattern in the variability in these range values

among girls was less consistent.

Socioeconomic. –Possible socioeconomic influences on the range of bone-specific skeletal

ages within individuals were analyzed in relation

to family income. The findings are not easily

interpreted. The median ranges tended to be

greater in the middle income group

($5,000-$9,000) than in either the higher or the

lower income groups, but this was true only at

ages 6, 8, 10, and 11 years for boys and 6-9

years for girls (table 14). In general, the present

data with respect to income-related differentials

do not demonstrate any definite effect of this

aspect of socioeconomic status on the range of

skeletal maturity within the hand-wrists of

United States children 6-11 years.

ONSET OF OSSIFICATION FINDINGS

Race

During ages 6-11 years, ossification usually

begins in the distal ulnar epiphysis, trapezium,

trapezoid, and pisiform in boys and in the

pisiform and adductor sesamoid in girls.

The differences in median ages of onset of

ossification between white and Negro children in

the United States as estimated from the present

Health Examination Survey are small and irregular in direction with the exception of the

trapezium in the boys, for which onset of

ossification (median age) was 1.5 years earlier in

the Negro group than in the white group (table

15). This may indicate that the modal order of

onset of ossification cliffers between these two

groups, but this finding needs confirmation

because the median age for Negro boys (4.9

years) is below the chronological age range of

the present study.

Other studies. –The data for white United

States children in table O are based on three

types of modal ages: (1) median age at onset of

ossification, (2) the mean age at onset of

ossification, and (3) the estimated age when the

center was ossified in 50 percent of the children.

The children in these samples were predominantly of Northeastern European ancestry and

of middle, or slightly above middle, socioeconomic status.

Hardin# 0 reported mixed longitudinal data

from white Boston children born between 1930

and 1939 and examined near each birthday. The

sample size varied from 63 to 67 at each age in

each sex. Baldwin et al.78 obtained mixed

longitudinal data from upper-middle-class white

children in Iowa City who were born between

27
Table O. Modal agas (in years) for onset of ossification in selected bones in U.S. white childran

Sex and bone

!

Modal age and reference

Boys

Distal ulna . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.7,s 4 7.1,788~9 7.2,80 7.4,s 1 7.4,6 7.2s 2

Trapezium . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.9,1 6rs4,79 fje2,7a,80 6.3,81 6.2a z

Trapezoid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.0,7 a &l,16,fJ0 6.2,79 6.4,34 6.8,81 6.2s 2

Pisiform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.0,80 11.2,’8 11.781

Girls —

Pisiform . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.4,80 8.681 9.0,’6 9.778

Adductorsesamoid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.7,79 11.3*’

1901 and 1928. There were from 28 to 49

children of each sex in each annual interval.

Mixed longitudinal data from middle-class white

children in Denver were reported by

Hansman.81 These children were born between

1915 and 1964, but most of the radiographs

were taken after 1947. Sample size varied from

39 to 57 for each 6-month ageintewal in each

sex.zs A mixed longitudinal study of white

Chicago children of above average socioeconomic status, born between 1911 and 1923,was

reportedby Flory.16 These children were radiographed within 2 weeks of a birthday. Radiographs were available for 100 children of each

sex at each age, except at 6 and 7 years when at

least 80 radiographs were available. Garnet al.79

reported mixed longitudinal data from middle

socioeconomic class whit e children in southwestern Ohio born between 1929 and 1966.

These children were radiographed within 1

month of each birthday and half-birthday. The

sample size was about 180 for each sex in each

6-month interval. Sproul and Peritz84 obtained

cross-sectional data from children of aboveaverage socioeconomic status living in or near

Oakland, California. The sample size for both

sexes combined was approximately 25 to 60

children at each annual interval from 6 through

8 years, with a further group of similar size

examined at 9 years or over. The children were

the 5 percent of the total sample neaxest to the

corresponding medians for stature.

In general, these data (table O) show that the

onset of ossification, during the age range

considered, tended to be later in the Denver

childrens 1 than in children in .Illinois, Ohio, or

Massachusetts.l6*79 ~s0 These differences are

unlikely to be due to racial or socioeconomic

factors, and they are not indicative of a secular

trend.

In a review of data from children of European

ancestry living outside the United States, the

emphasis will be on those countries from which

large numbers of immigrants have come to the

United States. Sempds8 reported median ages for

the onset of ossification of the adductor sesamoid and pisiform in French children, generally

of middle socioeconomic status, living in Paris

(table P). These children were born in 1953 and

radiographed close to birthdays and halfbirthdays. Skubiszewskag 4 used cross-sectional

data from 273 Warsaw children aged 7 to 14

years. The modal ages for these children are

similar to those reported for United States white

children of middle socioeconomic status (tables

5,0, and P).

Comparisons between modal ages for the

onset of ossification in Negro children living in

the United States and Negro children living in

Africa (table Q) are not easily interpreted. It is

Table P. Modal ages (in years) for onset of ossification in

children of EuroDean ancestrv Iivinrr in EuroDe

Sex and bone

Bovs

Pisiform. . . .

Girls

Pisiform. . . .

Adductor

sasamoid

French children Polish children

in Paris in Warsaw

(Semp& 1970)83 (Skubiszewska, 1964)84

Modal age

11.0

9.0

...

.-

11.0 10.7

28
Table Q. Modal agas (years) for onset of ossification of selected bones in Negro children living inside and outside the United States

Sex and bona

Bovs

Distal ulna . . . . . .

Trapezium . . . . . .

Trapezoid . . . . . .

Pisiform. . . . . . . .

Girls —

Pisifurm. , . . . . . .

Adductor sesamoid .

1 ! 1 I

Tan-State

Nutrition

p~~~~~~4*Da~~’T’ ‘“’”:3

Ovoioff children in Dakar, Senegal

Survay

(Gain et al.,

1972)az

6.7

5.8

5.7

-.

-.

---

6.6

6.1

6.3

---

...

--

Modal age

-. .- ...

-- -.. 6.7

-- — 6.7

--- 12.7 -.

10.5 11.8 10.5

12.5 ..- ---

7.0

4.9

6.1

--

8.9

10.7

impossible to identify groups of Negro children, number of radiomaphs available was about 40

in the United States or Africa, who belong to

the same relatively homogeneous genetic pool.

The data considered for Negro children in Africa

relate to the West Coast, from which large

numbers of slaves were imported into the United

States.s5 However, it is unlikely that the present

United States Negro population is representative

of the originaI slaves, or that the slaves were

representative of the African populations from

which they were taken.

The data of Garnet al.82 were obtained from

a large sample of children included in the

Ten-State Nutrition Survey. The data of Sproul

and Peritz3q were from California Negro children who were above average socioeconomically.

The sample size for both sexes combined was

approximately 18 for each annual interval; a

group of similar size was examined at age 9 years

or over. These children were the 5 percent of the

total sample who were nearest to the corresponding medians in stature. Mass: and Hunt86

reported cross-sectional data from Ovoloff girls

living in Dakar, Senegal. The total sample

included 100 children, both sexes combined,

examined near birthdays. They did not report

how many of these children were girls. MichautBarthodg 7 analyzed 628 radiographs of children

of Ovoloff ethnic origin Iiving in Dakar. Most of

the children were radio graphed three times near

birthdays or half-birthdays. All were more than

11 years old at their first radiograph, but the

data are useful for comparative purposes. The

for each sex at ~a~h 6-month interval. These

children were of low socioeconomic status even

by local standards. Mass&s8 obtained data from

a representative sample of 100 Dakar children

for each year of age of each sex.

Comparisons of these sets of data with those

from the present survey show that onset of

ossification tends to occur considerably earlier

in United States Negro children than those living

in Africa. The findings from the present national

survey are in fair agreement with those from a

small sample of California Negro children.s 4

The importance of genetic factors in determining age at onset of ossification is shown also

by numerous reports that, at younger ages than

those included in the present survey, Negro

infants and children are more advanced than

whites in this respect.

Sproul and Peritz34 reported data from a

cross-sectional study of upper-middle-class children of Chinese ancestry living in the San

Francisco area (table R). Most, but not all, of

these families came from the Kwangtung Province near Hong Kong.5 The sample size, for both

sexes combined, varied from 22 to 25 for each

annual interval from 6 through 8 years. An

additional 15 children were aged 9 years or over.

Data for Hong Kong children89 were obtained

from a cross-sectional study of children of low

socioeconomic status. The number in each anbLee, personalcommunication, 1972.

29
Table R. Modal ages (in Years) fOr onset of ossification of selected bones in children of Chinese ancestry living inside and

outside the United States

Table S. Modal ages (in yaars) for onset of ossification of se.

Iected bones in children of Japanese ancestry living inside

or outside the United Statas

Sex and bone

Boys I

Scaphoid . . . .

Distal ulna . . .

Trapazium . . .

Trapezoid . . .

Girls —

Distal ulna . . .

Chinese ancestryCalifornia

(Sproul and Peritz, 1971)34

Southern

Chinesa

in

Hong

Kong

(Laa et al.,

1868)’9

Modal age

6.4

8.1

5.8

6.0

6.7

7.2

8.7

6.7

6.9

7.8

Japanese ancastryCalifornia JapaneseSex end bone

(SProul and Peritz,

Hiroshima

1971)34 (Sutow, 1953)4 ‘

Boys Modal age

Scaphoid . . . . . . 7.2 7.1

Distal ulna . . . . . 8.2 8.4

Trapezium . . . . . 5.5 6.6

Trapezoid . , . . . 6.5 7.0

G&

Distal ulna . . . . . I 6.4 I 7.5

tween the large regions into which the United

States was divided for the .-purpose of this survey

(table 15).

nual interval varied from 10 to 27 of each sex.

The modal ages for onset of ossification were

markedly earlier in the California children than

in the Hong Kong children. These differences

probably reflect disparities between the populations in illness and nutrition; however, any

interpretations should be cautious because of

the small sample size. The retardation in the

Hong Kong children is almost certainly environmentally determined because at younger ages

they were ahead of southwestern Ohio white

children in the mean ages at onset of ossification.89

Table S contains data relating to the age”at

onset of ossification of selected hand-wrist

centers in California children of Japanese ancestry who were above average in socioeconomic

status.34 The sample size was small, varying

from 10 to 14 for both sexes combined at each

annual interval from 6 to 8 years; and 8 children

aged 9 years or over. Suto# 3- reported data

from a representative sample of normal Japanese

chiIdren in Hiroshima. The sample size for each

sex varied from 56 to 107 for each year of age.

The ages at onset of ossification tended to be

earlier for the children in California than for

those in Japan.

Geographic Region

As expected, the ages at onset of ossification

differed only slightly and nonsignificantly be30

Socioeconomic Factors

When children were grouped according to

family income, the median ages of onset of

ossification showed no relationship to this socioeconomic factor. The expected delay in onset

for those in lower income families was not

found among these United States children. The

lack of such an effect in the present national

survey may be partly due to the confounding

influence of racial differences. As noted earlier,

onset for the trapezium tended to be earlier in

Negro children, and these children were concentrated in the lower income groups.

Other studies.–The data included in table O

are from United States white children who were

middle class or above in socioeconomic status.

The present national study data are in agreement

with the previous findings from these smaller

samples with the exception of the age for the

trapezium in boys, which was slightly later in

the present white children and considerably

earlier in the Negro children.

Michelson O reported a mean age of onset of

ossification of the pisif orm in girls of 8.5 years

after studying 180 underprivileged white girls in

New York City for whom annual radiographs

were availabIe. The age of onset for each girl was

interpolated between the age of the last radiograph in which it was not ossified and the first

radiograph in which it was ossified. Conse-
quently, 0.5 year should be added to

Michelson’s reported mean before comparing it

with those lis~ed in table O. After this adjustment, the reported age is simiIar to those

reported from the studies listed, suggesting that

socioeconomic status is not a major determinant

of age at onset of ossification.

DISCUSSION

Throughout this discussion, comparisons will

be made between the national survey findings

and those from earlier studies. In interpreting

these comparisons, it is important to recall that

the present report describes the first national

survey of skeletal maturity levels for this or any

other country. While the methodology used in

the national survey was heavily dependent on

the work of previous investigators, differences

between the present and earlier findings should

be judged in relation to the accuracy of assessment and, most importantly? the representative

nature of the samples. In the national survey,

assessments were made of 94 percent of those

subjects initially identified by the National

Center for Health Statistics in collaboration with

the U.S. Bureau of the Census as constituting a

national proba~ility sample.

Race

It is difficult to interpret “racial” comparisons because groups almost always differ in

climate, nutrition, the prevalence of disease, and

frequently in socioeconomic status, to mention

some obvious factors. However, there is substantial evidence that genes influence the rate of

skeletal maturation. This evidence has come

from studies of pairs or triads of individuals

sharing similar environments but different proportions of genes. The reported genetic influences concern the order of onset of ossification,gl-gg its rate,92-94,96,100 -106 the

occurrence of skeletal variants, for example,

pseudoepiphyses,g 2$9q~101 Y102 levels of handwrist skeletal maturityl07 and the changes in

skeletal maturity with age.10 7-111

The mean skeletal ages for the white chiklren

included in the present national survey were

about 0.5 year below their corresponding chronological ages. This difference tended to increase

with age, which wouId indicate that the

Greulich-Pyle Atlas standards,6 based on a

specially selected subgroup of the population,

are higher than the mean values for U.S.

children. The corresponding differences between

chronological ages and Greulich-Pyle skeletal

ages are somewhat larger for Scot ch, British, and

Danish children, but the reports on Polish

children are conflicting; some indicate similar

delays and others that mean skeletal ages are

approximately equal to mean chronological

ages.2 5,26,31,32

The rates of skeletal maturation are more

rapid for Negro children in the United States

than for those in Jamaica.3 5‘39 Similarly, the

onset of ossification is delayed in African

chiIdren86‘88 in comparison with Negro children in the United States. Data for the latter are

available from the present national survey and

the sample of Sproul and Peritz.34

The national survey data show that Negro

children tend to mature skeletally somewhat

more rapidly than white children in the United

States. These small racial differences are statistically significant at only two ages in boys and

not at any ages in the girls. These findings are in

general agreement with those of earlier workers.z4*34‘3 g*112 When the data for all ages were

combined, the differences between whit e and

Negro children were significant at the 5-percent

level in boys but not in girls. Although the

present sumey has demonstrated a tendency for

Negro children to mature skeletally more rapidly

than white children, these differences are small

and most of them are not statistically significant

for single-year age groupings. These findings,

although real, are not of sufficient magnitude to

justify the creation of separate skeletal maturity

scales for these two racial groups.

Among both white and Negro children, there

was a tendency for skeletal age to be more

advanced in the girls (female equivalent values)

than in the boys; these differences were statistically significant at some ages. Earlier studies of

smaller, less representative groups of childrenl 6-19)22-24 have provided similar findings,

except that of Johnston,20 in which boys were

slightly more advanced than the girls on sex:

specific scales of skeletal maturity.

The national survey sample contained too few

children of Chinese or Japanese ancestry for

their data to be analyzed separately. Findings

31
from generally small and unrepresentative

groups have suggested that such children living

in the United States mature more rapidly than

children of similar ancestry living in their country of origk.s4*40S41S48-4GSblYs2

‘About-60 percent of the mean bone-specific

skeletal ages were more advanced in Negro

children than white children. Many of these

differences were statistically significant and consistent across age, indicating that cliff erent

modal patterns of hand-wrist maturation occur

between races. These differences” were generally

marked for the radius, ulna, capitat e, hamate,

triquetral, lunate, scaphoid, trapezium, and

metacarpal I-V, when considered within annual

intervals. Each of these bones was considerably

more advanced in Negro children. The pattern of

bone-specific skeletal ages (expressed as skeletal

age less chronological age) for all ages combined

was similar for each sex within each group.

While the means (SA-CA) for white children

were close to zero, the skeletal ages of the

radius, ulna, carpals and metacarpal were advanced about 3 months in Negro children. The

proximal phalanges II-V tended to be somewhat

more advanced in white than in Negro boys and

girls. In an earlier study, the radius was more

advanced in Negro boys than in white boys

living in Philadelphia.s6Y76 In the Negro girls,

the radius, ulna, metacarpal III, proximal phalanges I, III, and V, and distal phalanx I were

more advanced than in white girls. The magnitude of the bone-specific skeletaI age cliff erences

between white and Negro children found in this

survey and the earlier studys G~7G are probably

insufficient to justify separate standards for

Negro children. These differences are small but

real, however, and they are contrary to the

assertion of Greulich and PyleG that the pattern

of maturation is the same in all racial groups.

There are few previous relevant findings, but

tendencies to variations among bones in the

extents to which they differ from Greulich-Pyle

skeletal matunt y levels have been reported for

children in Hong Kong, Dakar, and Melbourne.a~sG~89

The assessments on which the present analysis

was based were made without knowledge of the

sex or race of any child, as previously mentioned. The small racial differences found among

boys and girls for each of the bone-specific

skeletal ages provide convincing evidence that

the assessments were highly reliable. Hence, the

remarkable similarity of race-specific patterns in

each sex, illustrated in figure 15, strongly

suggests that the differences between the racial

patterns are, indeed, real.

Geographic Region

Analyses of the national survey data by

geographic region were somewhat unrewarding,

largely because the four major geographic regions of the United States were too diverse to

demonstrate possible real differences, as discussed in an earlier report.1 13 After the effects

of differences in the age and racial distributions

were removed; children in the Northeastern and

Midwestern Regions tended to be advanced in

comparison with the others. This tendency

occurred for both white and Negro children.

However, most of the differences in skeletal

maturity (age at onset of ossification, means and

ranges of bone-specific skeletal ages and area

skeletal ages) could have been due to chance.

The mean skeletal ages tended to be more

advanced in girls (female equivalent values) than

boys in each region, but these differences were

statistically significant for few annual intervals.

In each region there was a decrease in the

coefficients of variabilityy with age from 6

through 10 years.

Real differences were not present between

urban and rural children in levels of skeletal

maturity. Presumably this reflects a corresponding lack of major differences between these areas

in factors that can influence the rate of skeletal

maturation. A similar lack of urban-rural differences in growth (body size) has been reported

for the United States and the factors responsible

have been reviewed fully.114

Socioeconomic Factors

These factors can influence skeletal maturation because they are related to child care,

particularly the quality of the diet and the

frequency of disease. Direct dietary measures

were not made in the national survey. Consequently, family income, which is highly correlated with the educationzd level of the father, is

32
used here as a measure of socioeconomic status

and an indirect measure of child care.

As expected, there was slight association

between socioeconomic status (income level)

and skeletal maturity in U.S. children from the

HES data. There was a consistent tendency

among white children for skeletal maturation to

be more rapid in the higher income groups.

Among Negro children, the pattern of association between family income and the rate of

skeletal maturation was less consistent, because

the sample size was not large enough to provide

consistently reliable estimates for that small

group. Previous studies in countries with much

more pronounced socioeconomic differences between segments of the population have demonstrateed higher skeletal maturity levels in upper

socioeconomic groups but the differences between the means for high and low socioeconomic groups did not exceed one year and were

considerably smaller in most studie~.26927 ,31,70-75

Comparisons between large samples from extreme groups are needed to determine whether

such effects are really present; the sample used

for the Health Examination Survey was not large

enough for this. When the HES bone-specific

skeletal ages for all races combined were considered within only three income groups, an association was not apparent. When the skeletal ages

for six representative bones were considered

within six income groups, there was a definite

pattern of more advanced maturity with increasing income. This is in general agreement with a

recent report from a 1968-70 Ten-State Nutrition Survey, contrasting ages at onset of ossification in high and low socioeconomic groups

separated on an income-needs ratio.l 15 In data

from the present national survey this effect was

most marked in the third and fourth proximal

phalanges and the fifth middle phalanx, indicating that these bones might be more sensitive

than other hand-wrist bones to environmental

effects.

Lower socioeconomic status is associated with

a higher frequency of illness during childhood.49 )116 Consequently, it is appropriate to

consider whether illness affects the rate of

skeletal maturation. Pryorl 17’118 may have

been the first to suggest that illness could retard

skeletal maturation. This occurs with severe

illnesses, but there may be an acceleration in

skeletal maturation during cat ch-up growth after

the illness. 119s 120

It has been claimed that even apparently

minor illnesses retard skeletal maturation in

preschool boys but not girls,l21 z122 but other

investigators have reported either no effects on

both sexesl 23-125 or effects on both sexes.l26

There is a general tendency for retarded onset

of ossification in the hand-wrist to be associated

with more childhood illness as reported on

health histories, but occasionally early onset of

ossification has been reported in association

with severe illness. 127 ~128 Other invest igators,

after excluding children with chronic diseases,

have found no association between illness and

the age of onset of ossification.l 28 Some

observers have reported that all cent ers are

retarded equally by childhood illness;1 29 others

that illnesses retard carpal cent ers more than

epiphyseal ones.l 19Y13O-132 Without reported

evidence, it has been claimed that illness, about

the time a center would have ossified,

retards its ossification but this has been denied.6~95~11g*128J133-136Such an effect would, of

course, give rise to unusual orders of ossification.

It .is difficult to summarize the findings of

studies concerning the effects of illness on the

rate of skeletal maturation, since these studies

differ in the methodology by which illness

histories were obtained and the influences of

possible confounding variables have been ignored. There seems to be little doubt that severe

illness can retard all phases of skeletal maturation, but no such conclusion would be justified

for minor illnesses.

Marked undernutrition retards skeletal maturation and dietary supplementation accelerates it,

both in experimental animals and children.18~70 ~137-139>140-147 Despite one contrary report,1 48 it is generally agreed that

m-akmtrit ion also retards the onset of ossification.60 ~149 In preschool Negro children this

delay is greater in boys than girls and is more

marked in the metacarpal than other hand-wrist

bones.l50 Others have stated that in older

Negro children the most sensitive hand-wrist

bones are the carpals and the distal end of the

ulna,63 ~141 but some have claimed almost the

reverse in African and Japanese children.41 ~143 ~151 These contradictions between

33
reported findings presumably result from differences in subject selection and methodology

among the studies cited, of which the most

obvious are the racial ones.

Reported findings that malnutrition has differential effects on maturation across bones

must be considered in relation to Todd’sl 8

attitude that the principle of assessment is the

utilization of the most advanced centers as a

guide to actual bodily maturity. This principle

would lead to use of the centers least sensitive to

environmental influences and thereby reduce the

sensitivity of assessments. The reportl52 that

the least retarded centers tend to respond most

when undernourished children are given dietary

supplements is analogous to the general growth

response to improvements in the environment.153 When adverse environmental factors,

such as famine, are operating, girls are less

affect ed than boys but they respond more

quickly than boys to a subsequent improvement

in the environment.154 Skeletal maturation is

slow also in children with ulcerative colitis,

regional enteritis or celiac disease, but “explosive” increases in the number of ossified centers

occur with treatment.155 ~156

In general, skeletal maturation is accelerated

in overfed experimental animalsl 57 and obese

children.158‘163 This acceleration is marked in

long term obesityl64 and especially when lean

body mass is increased also;165 it is greater in

the late than the early ossifying carpals.163

Few have studied the effects of specific

nutrients. Skeletal maturation is retarded in

gross malnutrition whether the main lack is in

“ 48,142,143,149 but protein calories or protein

intake may be the more important factor.166 A

lack of association between the level of calcium

intake, within the range studied, and the level of

skeIetaI maturity either at the same age or later

has been reported,l z3 but others have reported

a tendency to skeletal retardation with very low

calcium intakes.1G7 Relationships between the

age at onset of epiphyseal ossification and the

intakes of calcium and vitamin D have been

reported.1zOY13z

SUMMARY

The skeletal maturity levels in the hand-wrist

of noninstitutionalized children 6-11 years of

age in the United States as estimated from the

Health Examination Survey of 1963-65 have

been described and analyzed by race, area of

residence, and socioeconomic background in this

report. A probabilityy sample of 7,417 children

representative of the nearly 24 million noninstitutionalized children in the United States was

selected; of these, 7,119 (96 percent of the

sample) were examined. Radiographs of the

right hand-wrist suitable for assessment were

obtained from 6,962 (98 percent of the examined group or 94 percent of the total sample).

These radiographs were assessed by specially

trained medical students whu knew neither the

age nor the sex of any child whose radiograph

was assessed, thus eliminating several possible

sources of bias in these ratings. All assessments

were made against male standards; later the

skeletal ages for girls were adjusted by computer

to female equivalent values, bone by bone, using

the sex-associated clifferences in maturity reported by Pyle et al.g

The skeletal maturity levels of white boys and

girls 6-11 years of chronological age generally

tend to be somewhat lessadvanced than those of

Negro boys and girls in the United States. The

rates of skeletal maturation for Negro children

in the United States are more rapid than for

those Negro groups in Jamaica or in Africa

reported previously by others. Among United

States white and Negro children there is a

tendency for skeletal age to be more advanced in

girls than boys by approximately the same

magnitude in each race.

For 19 of the 31 individual hand-wrist bones

the mean skeletal age of United States white

children lags consistently behind that for Negro

children of corresponding chronological age,

with minor exceptions. In particular, mean

skeletal ages for the radius, ulna, all carpals, and

all metacarpal are advanced about 3 months in

Negro boys and girls compared with white

children, but the proximal phalanges are slightly

retarded. These racial differences are consistent

in both sexes; the clifferences between the two

groups of boys are similar to those between the

two groups of girls. These small but consistent

race-specific differences within each sex provide

strong evidence that the racial differences are

indeed real.

No statistically significant differences among

geographic regions of the United States were

found in the levels of skeletal maturity, although

children in the Northeast and Midwest tended to

34
be more advanced in this respect than those in

the West and South.

No urban-rural difference was found in the

skeletal maturity levels of United States children.

Socioeconomic status as measured by family

income levels shows a slight but generally

consistent relationship to the level of skeletal

maturity of United States children 6-11 years of

chronological age, with a pattern of increasing

skeletal maturity with increasing income.

These national estimates of skeletal maturity

levels for children 6-11 years of chronological

age delineate for the first time the approximate

magnitudes of the clifferences in these levels

between races, broad geographic regions of the

United States, and socioeconomic groups. Although real, these racial, socioeconomic, and

geographic differences in skeletal maturity

among United States children are not considered

large enough to justify the creation of separate

standards.

000

35
REFERENCES

1National Center for Health Statistics: Skeletal maturity of children 6-11 years, United States. Vital and

Health Statistics. Series 1l-No. 140. DHEW Pub. No.

(HRA) 75-1622. Health Resources Administration.

Washington. U.S. Government Printing Office, Nov.

1974.

‘National Center for Health Statistics: Origin, program, and operation of the U.S. National Health Survey.

Vital and Health Statktics. PHS Pub. No. 1000-Series

l-No. 1. Public Health Service. Washington. U.S. GovernmentPrinting Office, Apr. 1965.

3National Center for Health Statistics: Plan and

initial program of the Health Examination Survey. Vital

and Health Stattktics. Series l-No. 4. DHEW Pub. No.

(HRA) 741038. Health Resources Administration.

Washington. Government Printing Office, Nov. 1973.

4National Center for Health Statistics: Cycle I of the

Health Examination Survey: Sample and response,

Unit ed States, 1960-1962. Vital and Health Statzktics.

PHS Pub. No. 1000-Series 1l-No. 1. Public Health

Service. Washington. U.S. Government Printing Office,

Apr. 1964.

5National Center for Health Statistics: Plan, operation, and response results of a program of children’s

examinations. Vital and Health Stat&ics. Series l-No. 5.

DHEW Pub. No. (HSM) 73-1251. Health Services and

Mental Health Administration. Washington. U.S. GovernmentPrinting Office, Oct. 1967.

6Greulich, W. W., and Pyle, S. I.: Radio~aphic Atlas

of Skeletal Development of the Hand and Wrist. (2nd

cd.) Stanford, Calif. Stanford University Press, 1959.

7Roche, A, F.: Lateral compsxisons of the skeletal

maturity of the human hand and wrist. Am. J.RoentgenoLRadium Ther.NucLMed. 89(66):1272-1280, June

1963.

8 Roche, A. F., Davila, G. H., Pasternack, B. A., and

Walton, M. J.: Some factors influencing the replicabiMy

of assessments of skeletal maturity (Greulich-Pyle).

Am.J.Roentgenol. Radium Ther.NucLMed. 109(2):299-

?306,June 1970.

9Pyle, S. I., Waterhouse, A. M., and Greulich, W. W.:

A Radiographic Standard of Reference for the Growing

Hand and Wrist: Prepared for the United States National

HeaLth Examination Survey. Chicago. The Press of Case

Western Reserve University, 1971.

10Malcolm, L. A.: Growth and development of the

Bundi child of the New Guinea highlands. Hum. Biol.

1

42(2 :293-328, May 1970.

1 Romanus, T.: Menarche in school girls. Acts

Genet. S$atk. (Basel) 3:50-60,1952.

12Meredith, H. V.: Body size of contemporary

groups of preschool children studied in different parts of

the world. Child Dev. 39(2):335-377, June 1968.

13Meredith, H. V.: Body size of contemporary

groups of eight-year-old children studied in different

parts of the world. Monogr. Soc.Res, Child Dev.

2

34(1 :1-93, 1969.

1 Meredith, H. V.: Body size of contemporary youth

in different parts of the world. Monogr. Soc.Res. Child

Dev. 34(7):1-120, 1969.

15Malcolm, L. A.: Growth and development in New

Guinea-A study of the Bun& people of the Madang

district. Monogr.Inst.Human BioL, Papua-New Guinea

1:1-105, 1970.

16 Flory, C. D.: Osseous development in the hand as

an index of skeletal development. Monogr. So c.Res. Child

Dev. 1.1(3):1-141, 1936.

17 Simmons, IS.: The Brush Foundation study of

child growth and development. II. Physical growth and

development. Monogr. Soc.Res. Child Dev. 9(1):1-87,

1944.

18Todd, T. W.: At~s of Skeletal Maturation. St.

Louis. C. V. Mosby Co., 1937.

19Bayley, N.: The accurate prediction of growth and

adult height. Mod. ProblPaedkzt. 7:234-255, 1962.

20Johnston, F. E.: A Longitudinal Study of Skeletal

Maturation and Its Relationship to Growth in Philadelphkz White Children; A Dissertation in Anthropology.

Ph.D. dusertation, University of Pennsylvania, Philadelphia, 1962.

21 Krogman, W. M.: Growth of head, face, trunk, and

limbs in Philadelphia white and Negro children of

elementary and high school age. Monoq. Soc.Res. Child

Dev. 35(3):1-80, 1970.

22 Fry, E. I.: Skeletal age b y Guess and by Tanner. II.

Large sample analysis. Amer. J.Phys.Anthropol. (abstract). 25:202, 1966. (Plus personal communication.)

23Maresh, M. M. Measmements from roentgenograms, heart size, long bone lengths, bone, muscle and

fat widths, skeletal maturation. In Human Growth and

Development (R. W. McCammon, Ed.). Springfield, 111.

Charles C. Thomas, 1970.

24Todd, T. W.: Differentkl skeletal maturation in

relation to sex, race, variability and disease. Child Dev.

2:49-65,1931.

25Tmn@, J. M., Whitehouse, R. H., and Healy, M. J.

R.: A New System for Estimating Skeletal Maturity

j%om the Hand and Wrkt, with Standards Derived from a

Study of 2,600 Healthy Britirh Children. H. The Scoring

System. Paris. International Children’s Centre, 1962.

36
‘26An&r~en, E.s sk~l~t~l ~atwationof D~ish school

children in relation to height, sexual development, and

social conditions. Acts Paediatr. Stand. (Suppl.)

185:1-133, 1968.

27 Asiel, M.: Consid<mtions sur l’util~ation des mtjth.

odes de Greulich et Pyle et de Tanner pour I’evaluation

de la maturation osseuse d’un Echantillon de garcons

agis de cinq a neuf ans. In Compt e R endu de la Reunion

des Equipes Charge>s des Etudes sw la Croiwance et le

Dt%eloppement de l’Enfant Normal. Vol. 1. Stockholm.

Centre International de l’Enfance, 1966, pp. 53-59.

28Roche, A. F., Davila, G. H., and Eyman, S. L.: A

comparison between Greulich-Pyle and TannerWhitehouse assessments of skeletal maturity. Radiology

J

98(2 :273-280, Feb. 1971.

2 B]anco, ~ A., A~heson, R. M., Cmom, C., md

Salom6n, J. B.: Height, weight, and lines of arrested

growth in young Guatemala children. Am.J.Phys.AnthropoL 40(1):39-47, Jan. 1974.

30 Roche, A, F.: A study of skeletal maturation in a

group of Melbourne children. Aust.Paediutr.J.

i

3(3 :123-127, Sept. 1967.

1Kopczynska, J.: Determination radiologique de la

maturation osseuse. (Radiological determination of skeletal maturation.) Ann. RadioL (Park) 7(5-6):308-314,

1964.

32 Rudzirkki, B. W.: Puberty and its indices in hand

and wrist radiograms in boys from Warsaw schools.

Pediatr.Pol. 45(12):1447-1461, Dec. 1970.

33Cha’vez, A., Hidalgo, C. P., and Pitol, A.: Maduracion osea en dos grupos de ni~os con diferente estado

de nutrition. Salud Publics Me*, 6(4):705-717, 1964.

34 Sproul, A., and Peritz, E.: Assessment of skeletal

age in short and tall children. Am.j.Phys.AnthropoL

35(3) :433-439, Nov. 1971.

35Malina, R. M.: Patterns of development in skinfolds of Negro and white Philadelphia children.

Hum.Biol 38(2):89-103, May 1966.

36Ma]ina, R. M.: Skeletal maturation rate in North

American Negro and white children. Nature 223:1075,

Sept. 6, 1969.

37Mafina, R. M.: Skeletal maturation studied longitudinally over one year in American whites and Negroes

six through thirteen years of age. Hum. Biol.

J

42(3 :377-390, Sept. 1970.

3 Malina, R. M.: Personal communication, 1972.

39~~~sha~, W. A., AshCroft, M. T., and Bryan, G.:

Skeletal maturation of the hand and wrist in Jamaican

children. Hum.BioL 42(3):419-435, Sept. 1970.

40Low, W. DO, Chan, & T., c~ng, K. S.F., and Lee,

M. M. C.: Skeletal maturation of southern Chinese

children. Child Dev. 35(4):1313-1336, Dec. 1964.

41 Greufich, W. W.: A comparison of the physical

growth and development of American-born and native

Japanese children. Am.J.Phys.AnthropoL 15(4)489-515,

Dec. 1957.

42 Greulich, W. W., and Pyle, S. I.: Radiographic Atlas

of the Skeletal Development of the Hand and Wrkt.

Stanford, Calif. Stanford University Press, 1950.

43 Sutow, W. W.: Skeletal maturation in healthy

Japanese children, 6 to 19 years of age: Comparison

with skeletal maturation in American children. Hiroshima JMed. Sci 2(1-2)181-191, Mar. 1953.

44 Sutow, W. W., and Ohm&, K.: Ske]etal st~d~ds

of healthy Japanese children from age 6 to 19 years.

Clin.Pediatr. (Japan) 6:738-746, 1953.

45 Sugiura, Y., and Nakazawa, O.: Bone Age: Roentgen Diagnosis of Skeletal Devleopment. Tokyo. Chugai

Igakusha, 1968.

46 Kimura, K.: Roentgenographic studies of the hand

and wrist bones in Japanese-American hybrids.

]ap.Soc.EthnoL, 20th session. 188-190,1965.

47 Kim~a, K.: On the skeletal maturation of the

Japanese-American hybrids. A preliminary report.

J.Anthrop.Soc. Nippon 79:21-29,1971.

48~nman, C. F., and Maresh, M. M.: A longitudinal

study of skeletal maturation. Am.J.Dis. Child 101(3):

305-321, Mar. 1961.

49 National Center for Health Statktics: Examination

and health history findings among children and youths

6-17 years, United States. Vital and Health Statistics.

Series 11-No. 129. DHEW Pub. No. (HlU4) 741611.

Health Resources Administration. Washington. U.S. Government Printing Office, Nov. 1973.

50 Dearborn, W. F., and Rothney, J. W. M.: Predicting

the Child’s Development. Cambridge, Mass. Sci-Art

Publishers, 1941.

51 Dearborn, W. F., Rotbney, J. W. M., and Shuttleworth, F. K.: Data on the growth of public school

children (from the materials of the Harvard Growth

Study). Monogr. Soc.Res. Child Dev. 3(1):1-136, 1938.

52 MiIIS, C. A.: Geographic and time variations in

body growth and age at menarche. Hum.Biol

9(1):43-56, Feb. 1937.

53M~s, C. A.: Temperature influence over human

growth and development. Hum.BioL 22(1):71-74, Feb.

1950.

54 Fabry, C.: La fixation de chaux par le phosphate

tricalcique en milieu aqueux. Biochim.Bio@hys.Acts

14(3):401-406, July 1954.

55 Brookes, M., and May, K. U.: The influence of

temperature on bone growth in the chick. J.Anat.

lll(Pt. 3):351-363, Apr. 1972.

56Barnett, S. A., and Coleman, E. M.: The effect of

low environmental temperature on the reproductive

cycle of female mice. J. EndocrinoL 19(3) :232-240, Dec.

1959.

57 B~ett, S. A.: Genotype and environment in tail

length in mice. Q.J.Exp.PhysioL 50(4):417-429, Oct.

1965.

58Lee, M. M. C., Chu, P. C., and Chan, H. C.: Effects

of cold on the skeletal growth of albino rats. Am.J.Anat.

124(2):239-249, Feb. 1969.

59 Lee, M. M. CO, Chu, p. C., ad Chan, H. C.:

Magnitude and pattern of compensatory growth in rats

after cold exposure. J. EmbryolExp.Morphol. 21(3):

407-416, June 1969.

60 Nissen, H. W., and Riesen, A. H.: Retardation in

onset of ossification in chimpanzee related to various

environmental and physiological factors. Anat. Rec.

105(4):665-675, Dec. 1949.

6I Sawtell, R. O.: Ossification and growth of children

37
frhm one to eight years of age. Am.J.Dis. Child

4

37(1 :61-87, Jan. 1929.

6 Reynolds, E. L., and Sontag, L. W.: Seasonal

variations in weight, height, and appearance of ossification centers. J.Pediatr. 24(5):524535, May 1944.

69 Dreizen, S., Snodgrasse, R. M., Webb-Peploe, H.,

Dreizen, J. G., and Spies, T. D.: The sites of maturational strength and weakness in the developing hand

skeleton. Am.J.Roentgenol. Radium Ther.Nucl.Med

1

82(3 :490-500, Sept. 1959.

6 Wolanski, N., and Lasota, A.: Physical development of countryside children and youth aged 2 to 20

years as compared with the development of town youth

of the same age. Z.Mor@AnthropoL 54(3):272-292,

Jan. 1964.

65 Stettier, E.: &er die Beziehungender Ossification

des Handskeletts zu Alter und L5ngenwachstum bei

gesunden und Kranken Kindem von der Geburt bis zur

Pubertiit. ArcL$K(7derh. 68:342-368, 1920.

66 Stettner, E.: Uber die Beziehungen der Ossification

des Handskeletts zu Alter und Hingenwachstum bei

gesunden und Kranken Kindern von der Geburt bis zur

Pubert&. Arch.j Kinderh. 69:27-62, 1921.

67 Stettner, E.: Wer die Beziehunger der Ossification

des Handskeletts zu Alter und L5ngenwachstum. bei

gesunden und Kranken Kindem von der Geburt bis zur

Pubert&. Arch.$Kinderh. 68:439-466, 1920.

68 National Center for HeaIth fjtatktics: Inte~ectual

development of children by demographic and socioeconomic factors, United States. Vital and Health

Statistics. PHS Pub. No. 1000-Series 1l-No. 110. Public

Health Service. Washington. U.S. Government Printing

Office, Dec. 1971.

69 Chmg, K. S. F., Lee, M. M. C., Low, W. D., ad

Kwan, E.: Height and weight of southern Chinese

children. Am.J.Phys.Anthropol. 21(4) :497-509, Dec.

196%

70Grade Coviin, F., and Rof (&bauo, J.: ~imentacion y desarrollo infantil. IV. Comunicati6n. Estudio

radiogrdfico comparative del desarrollo esque16tico de

dos grupos de niiios en edad escolar y distiuto nivel

econ6mico. Rev. ClimEsp. 14(1): 13-16, July 1944.

71 DeWijn, J. F.: Summarizing the survey and comments on the interrelationship between data obtained by

medical inspection, biochemical investigations and diet

of schoolchildren (1950-51) of three clifferent social

classes. Verb.Inst.Praev. Geneesk. 22:167-183, 1953.

~2Young, E. B., Tesi, G., Jessor, R.; Young, H. B.:

Some somatic and psychological observations on young

children in a poor suburb of a North African city. In

Compte Rendu de la Re%nion des Equipes Charg4es des

Etudes sur la Crohsance et le D.4veloppement de l’Enfant

Normal. Vol. 2. Stockholm. Centre International de

l’Enfance, 1966, pp. 113-116.

73 Rea, Jo N. g social and economic influences on the

growth of pre-school children in Lagos. Hum. Biol.

43(1):46-63, Feb. 1971.

74 Neyzi, 0,, Yalqinda~, A., and Alp, H.: Socioeconomic level and physiological maturation in the Turkish

child. In Growth and Development: Proceedings of XIII

International Congress of Pedtitrics 15:55-60, 1971.

75 Acheson, R. M., and Hewitt, D.: Oxford Child

Health Survey: Stature and skeletal maturation in the

pre-school child. Br.J.Prev.Soc.Med. 8(1):59-65, Jan.

1954.

76Malina, R. M.: Growth, maturation, and performance of Philadelphia Negro and white elementary school

children. Unpublished doctoral dissertation. University

of Pennsylvania, Philadelphia, 1968.

77 Peritz, E., and Sproul, A.: Some aspects of the

analysis of hand-wrist bone-age readings. Am. J.Phys.AnthropoL 35(3) :441-447, NOV. 1971.

78Baldwin, B. T., Busby, L. M., and Garside, H. V.:

Anatomic growth of children: A study of some bones of

the hand, wrist, and lower forearm by means of

roentgenograms. Univ.Iowa Studies in Child Welfare

4(1):1-85, 1930.

79 Gain, S, M., Rohmann, C, G., ad Sflvermn, F+

N.: Radiographic standards for postnatal ossification and

tooth calcification. Med. Radiogr.Photogr. 43(2):45-66,

1967.

80 Haxdrng, V. S. V.: A method of evaluating osseous

development from birth to 14 years. Child Dev.

1

23(4 :247-271, Dec. 1952.

8 Hansman, C. F.: Appearance and fusion of ossification centers in the human skeleton. Am.J. RoentgenoLRadium Ther.Nucl.Med 88(3):476-482, Sept. 1962.

82Gam, S. M., Sandusky, S. T., Nagy, J. M., and

McCann, M. B.: Advanced skeletal development in

Iow-income Negro children. J.Pedtitr. 80(6):965-969,

June 1972.

83 Semp/, M.: Ages d’apparition du pisiforme et des

sesamoids. In Compte Rendu de la Xe R #union des

Equipes Charg4es des Etudes sur la Croiwance et le

D&eloppement de l’Enfant Normal, Davos, Suirse,

1970. Paris. Centre International de L’Enfance, 1970, p.

95.

84 Skub~zewska, B. fiocess of ossification in the

hand and of second dentition as indicators of developmental age in children. Research Reports. Warsaw.

National Research Institute of Mother and Child.

3:229-231,1964.

8 f/Donnan, E.: The slave tmde ~to South (jmol~a

before the Revolution. Am. Hist.Rev. 33:816-817, 1928.

86 Maw&, G-, and Hunt, E. E., Jr.:skeletal maturation

of the hand and wrist in West African Children.

Hum,Biol 35(1):3-25, Feb. 1963.

87Michaut-Barthod, E.: Determination de la matu~.

tion osseuse de 227 adolescents Dakarois par la mdthode

de Tanner-Whitehouse-HurIey et par I’Atlas de Greulich

et Pyle, Unpublished doctoral dissertation, University of

Paris, 1971, pp. 1-58.

88Mass<, G.: Croissance et d6veloppement de l’enfant

a’ Dakar. Paris. Centre Intematioml de l’Enfance, 1969,

pp. i-iii, 1-263.

89Lee, M. MOCO,G~n, S0Ma, Rohmaml, C. G., and

McPhaden, P. W.: The clustering phenomenon and

group-sequence of hand-wrist ossification centers, as

illustrated by Chinese children from Hong Kong.

Hum.BioL 40(3):345-362, Sept. 1968.

9oMiche150n;N.: Studiegin the

ment. V. The ossification time of

Hum.BioL 17(2):143-146, May 1945.

physical developthe os pisiforme.

38
91 Pryor, J. W.: The hereditary nature of variation in

the ossification of bones. Anat.Rec. 1(4):8488, May 1,

1907.

92 Pvor, J. W.: Normal variations in the ossification

of bones due to genetic factors. J.Hered. 30(6): 249-255,

June 1939.

98Hess, A. F., and Abramson, H.: Famflial ~etmdation in ossification of the carpal centers. J.Pedtitr.

!/

3(1 :158 -165, July 1933.

4Key, W. E.: Radiological studies of the skeletons of

twins, triplets and quach-uplets. J.Hered. 27(1):86-88,

Jan. 1936.

9 bsontag,L.w. and Lipford, J.: The effect of illness

and other factors on the appearance pattern of skeletal

epi hyses. J.Ped&ztr. 23(4) :391-409, Oct. 1943.

~6Garn, S. M., and Rohmnn, C. G.: pwent.chi~d

similarities in hand-wrist oss~lcation. A m.J.Dis. Child.

$

103 4):603-607, Apr. 1962.

9 Hertzog, K. P., Falkner, F., and Garn, S. M.: The

genetic-determination of ossification sequence polymorphism. Am.J.Phys.Anth.ro# oZ. 30(l): 141-143, Jan.

1969.

98 Reynolds, E. L.: Degree of kinship and pattern of

ossification: A longitudinal X-ray study of the appearance pattern of ossification centers in children of

different kinship poups, Am. J.Phys.Anthropol

J

1(4 :405-416, Dec. 1943.

9Sontag, L. W., and Reynolds, E. L.: Ossification

sequences in identical triplets: A longitudinal study of

resemblances and differences in the ossification patterns

of a set of monozygotic triplets. J. Hered. 35(2):57-64,

Feb. 1944.

10OPryor, J. W.: Time of ossification of the bones of

the hand of the male and female and union of epiphyses

with the diaphyses. Am.J.Phys.Anthropol. 8(4) :401-

410, 1925.

101 Pryor, J. W.: Ossification as additional evidence in

differentiating identical and fraternal in multiple

births. Am.J.Anat. 59(3):409-423, Sept. 1936.

102Buschke, F.: The radiological examination of the

skeletons of triplets. J.Hered. 26(10):391-410, Oct.

1935.

103 G~n, S. M., Rohmann, C. GO,and Davis, A. A.:

Genetics of hand-wrist ossification. Am. J.Phys.Anthropo~ 21(1):33-40, Mar. 1963.

104Garn, S. M.: Determinants of size and growth

during the first three years. In The Growth of the

Normal Child During the First Three Years of Life,

Modern Problems in Pediatrics (A. Merminod, cd.) Vol.

7. Basel. S. Karger, 1962, pp. 50-55.

105Lund, S. E. T.: A psycho-biological study of a set

of identical girl triplets. Hum.BioL 5(1): 1-34, Feb. 1933.

106 Parkin, J. M., Neligan, G. A., Dee, P. M., and

Simpson, W.: The influence of genetic differences,

nutrition and sex on the radiological appearances of the

lower limb ossification centres in newborn twins.

Hum.Biol. 41(1):1-12, Feb. 1969.

107Hewitt, Do: Some familial correlations in height,

weight and skeletal maturity. Ann.Hum. Genet. 22 (Pt.

1):26-35, Oct. 1957.

108 Rigler, L. G.: Roentgen studies of twins and

triplets. Radiology 30(4) :461-470, Apr. 1938.

109 Simmons, K., and Greulich, W. W.: Menarcheal

age and the height, weight, and skeletal age of girls age 7

to 17 years. J.Pedziztr. 22(5) :518-548, May 1943.

110 Reynolds, E. L., and Schoen, G.: Growth patterns

of identical triplets from 8 through 18 years. Child Dee.

)

18(3 :130-151, Sept. 1947.

1 1Pyle, S. J., Reed, R. B., and Stuart, H. C.:

Patterns of skeletal development in the hand. Pedzhtrics

24(5, Pt. 11):886-903, NOV. 1959.

112 Garn, S. M., Sandusky, S. T., Nagy, J. M., and

McCann, M. B.: Advanced skeletal development in

low-income Negro children. J.Pediatr. 80(6):965-969,

June 1972.

113National Center for Health Statistics: Height and

weight of children 6-11 years, by age, sex, race, and

geographic region – United States. Vital and Health

Statktics. PHS Pub. No. 1000-Series 1l-No. 104. Public

Health Service. Washington. U.S. Government Printing

Office, Sept. 1970.

114Nation~ center for Health Statistics: Height and

weight of children: Socioeconomic status, United States.

Vital and Health Statzktlcs. PHS Pub. No. 1000-Series

1l-No. 119. Public Health Service. Washington. U.S.

Government Printing Office, Oct. 1972.

115Garn, S. M., Sandusky, S. T., Rosen, N. N,, and

Trowbridge, F.: Economic impact on postnatal ossification. Am.J.Phys.Anthropol. 38(1): 1-4, Jan. 1973.

116Douglas, J. W. B., and Blornfield, J. M.: ChiZdren

Under Five. London. George Allen and Unwin, 1958.

117 ~Yor, J. w.: chronology and order of ossification

of the bones of the human carpus. Univ. of Kentucky

Bu~~.IX, 1908.

118prYor, J. W.: Some observations of the ossification of the bones of the hand. Univ. of Kentucky Bull.

8, 1916.

119 Francis, C. C.: Factors influencing appearance of

centers of ossification during early childhood.

Am.J.Dis. Child. 57(4):81 7-830, Apr. 1939.

120 Prader, A., Tanner, J. M., and von Harnack, G.

A.: Catch-up growth following illness or starvation: An

example of developmental canalization in man.

J.Pediztr. 62(5):646-659, May 1963.

121 Acheson, R. M., Hewitt, D., Westropp, C., and

MacIntyre, M. N.: Some effects of adverse environmental circumstances on skeletal development (abslract). Am.J.Phys.Anthropol. 14(2) :375, June 1956.

122 Falkner, F.: Skeletal maturation; an appraisal of

concept and method. Am. J.Phys.AnthropoL 16:381-

396, 1958.

123 Cahn, A., ~d Roche, A. F-: me influence of

illness and calcium intake on rate of skeletal maturation

in children. Br.J.Nutr. 15(3):411417,1961.

124Bashe, W. J., Jr., and Ratner, B.: Bone development in children with tuberculosis. I. Maturation determined by the Todd method. Quart.Bull. Sea View Hosp.

i

15(2 :49-61, Apr. 1954.

1 5Bashe, W. J., Jr., and Ratner, B.: Bone development in children with tuberculosis. III. Studies with the

red graph. Quart.Bull. Sea View Hosp. 15(2): 71-82, Apr.

1954a.

126Hewitt, D., Westropp, C. K., and Acheson, R. M.:

Oxford Child Health Survey: Effect of childish ailments

39
on skeletal development. Br.J.Prev. So c.Med. 9(4):179-

186, Oct. 1955.

I Z7Stuart, H. C., and Vickers, V.: Variations in

ossification pattern observed during first five years.

Am.J.Dis. Child. 52(3):753-755, Sept. 1936.

128Tiisala, R., Kantero, R. L., and B5ckstrom, L.:

The appearance pattern of skeletal epiphyses among

normal Finnish children during the first five years of life.

Ann.Pedtitr.Fenn. 12(2):64-72, 1966.

129 Pyle, I., and Sontag, L. W.: Variability in onset of

ossification in epiphyses and short bones of the extremities. Am.J.Roentgenol. Radium Ther.NucLMed. 49(6):

795-798, June 1943.

13 OTodd, T. W.: Growth and development of the

child: Part IL Anatomy and Physiology. White House

Conference on Child Health and Pro tectio~ 1930. New

York. Century Co., 1932.

131 BueM, Co C., and Pyle, S. I.: The use of age at

first appearance of three ossification centers in determining the skeletal status of children. J.Pediatr.

2

21(3 :335-342, Sept. 1942.

1 2 Francis, C. C.: Factors influencing appearance of

centers of ossification during early childhood. IL A

comparative study of degree of epiphysial ossXlcation in

infancy under varying conditions of diet and health.

Am.J.Dk Child. 59(5):1006-1012, May 1940.

133 Hansman, C. F., and Maresh, M. M.: A longitudinal study of skeletal maturation. A m.J. Dir. Child.

101:305-321, 1961.

134 Francis, C. C., and Werle, P. P.: The appearance

of centers of ossification from birth to 5 years.

Am.J.Phys.Anthropol. 24(3):273-299, 1939.

135Pryor, H. B., and Carter, H. D.: Phases of

ado 1escent development in girls. Cakjl West.Med

J

48(2 :89-94, Feb. 1938.

1 6GreuIich, W. W.: The relationship of skeletal

status to the physical growth and development of

children. In Dynamics of Growth Processes (E. J. Boell,

cd.). Princeton, N.J., Princeton University Press, 1954,

pp. 212-223.

137MacNah, V., and Roberts, Lo Jo: Effect of a filk

supplement on the physical status of institutional

children. II. Ossification of the bones of the wrist.

A m.J.Dis. Child. 56(3):494509, Sept. 1936.

138MacNair, V.: Effect of a dietary supplement on

ossification of the bones of the wrist in institutional

children. II. Effect of cod liver oil supplement.

Am.J.Dis. Child. 58(2):295-319, Aug. 1939.

139 Daniels, A, L.: Relation of calcium, phosphorus

and nitrogen retention to growth and osseous development: A long time study of three preschool boys.

Am.J.Dis. Child. 62(2):279-294, Aug. 1941.

140Mack, P. B., and Urbach, C.: A study of institutional children with particular reference to the caloric

value as well as other factors of the dietary.

Mono .Soc.Res. Child Dev. 13(1):1-93, 1948.

14~Abbott, 0. D., Townsend, R. O., French, ROBO,

and Ahmann, C. F.: Carpal and epiphysial development:

Another index of nutritional status of rural school

children. Am.J.Dk Chili. 79(1):69-81, Jan. 1950.

142Berridge, F. R., and Prior, K. M.: The skeletal

development of the children at the beginning and end of

the period of experimental feeding. MecLRes. Count.

Spec.Rep. Ser. No. 287(Appendix D): 119-130, 1954.

143Jones, p. R. M., and Dean, R. F. A.: The effects

of kwashiorkor on the development of the bones of the

hand. J. Trop.Pediatr. 2(2) :51-68, Sept. 1956.

144Silberberg, R., and Silberberg, M.: Changes in

bones and joints of underfed mice bearing anterior

hypophyseal grafts. Endocrinology 60(1) :67-75, Jan.

1957.

145 Spies, T. D., Dreizen, S., Snodgrasse, R. M.,

Arnett, C. M., and Webb-Peploe, H.: Effect of dietary

supplement of nonfat milk on human growth failure:

Comparative response in undernourished children and in

undernourished adolescents. Am.J.Dis. Child 98(2):187-

197, Aug. 1959.

146Acheson, R. M., Fowler, G. B., and Janes, M. D.:

Effect of improved care on the predicted adult height of

undernourished children. Nature 194735-736, May 26,

1962.

147Dreizen, S., Snodgrasse, R. M., Webb-Peploe, H.,

and Spies, T. D.: The effect of prolonged nutritive

failure on epiphyseal fusion in the human hand skeleton.

Am. J. Roentgen ol. Radium Ther. Nucl. Med.

)

78(3 :461-470, Sept. 1957.

1 8Behw, MO, Rohmann, C., Wilson, D., Vlteri, F.,

and Garn, S. M.: Osseous development in children with

kwashiorkor (abstract). Fee!.FYoc. 23(2, Pt. I): 338,

1964.

149 Frisancho, A. R., Garn, S. M., and Ascoli, W:

Childhood retardation resultrng in reduction of adult

body size due to lesser adolescent skeletal delay.

Am.J.Phys.AnthropoL 33(3):325-336, Nov. 1970.

150 Dreizen, S., Snodgrasse, R. M., Webb-Peploe, H.,

and Spies, T. D.: The retarding effect of protracted

undernutrition on the appearance of the postnatal

ossification centers in the hand and wrist. Hum.Biol

30(4):253-264, Dec. 1958.

151 Dean, R. F. A.: The effects of m~utrition on

the growth of young children. Mod?%obLPaedziztr.

5:111-122,1960.

1.52~eizen, s,, sno~asse, R+ M., p~ker, G. s.,

Currie, C., and Spies, T. D.: Maturation of bone centers

in hand and wrist of children with chronic nutritive

failure: Effect of dietary supplements of reconstituted

milk solids. Am. J. Dis. Child. 87(4):429-439, Apr. 1954.

153 Greufich, W. W.: The growth and developmental

status of Guamanian school children in 1947.

Am.J.Phys.AnthropoL 9:55-70,1951.

154wi&jowwn, E. M., ~d Mc~nce, R. A.: studies

on the nutritive value of bread on the effect of variatiom

in the extraction rate of flour on the growth of

undernourished children. MecLRes. Count. Spec.Rep. Ser.

No. 287, 1954.

155McCaffery, T. D., Nasr, K., Lawrence, A. M., and

Kirsner, J. B.: Severe growth retardation in children with

inflammatory bowel disease. Pedtitrics 45(3, Pt.

1):386-393, Mar. 1970.

156Shmerting, D. H., Prader, A., and Zachmann, M.:

The effect of dietary treatment on growth in coeliac

disease. In Calorie Deficiencies and Protein Deficiencies

(R. A. McCance and E. M. Widdowson, eds.) London. J.

&A. Chwchill, Ltd. 1968, pp. 159-161.

40
157Dickerson, J. W. T., and Widdowson, E. M.: Some

effects of accelerating growth. II. Skeletal development.

fioc.R.Soc.Lend.(BioL) 152(947) :207-217, May 17,

1960.

158Bruch, H.: obesity in childhood: I. Physical

growth and development of obese children. Am.J.Dis.-

Child. 58(3):457-484, Sept. 1939.

159Mossberg, H-O.: The X-ray appearance of the

knee joint in obese overgrown children. Acts Paedtitr.-

Stand. 38:509-516,1949.

160 Fry, P. C.: A comparative study of “obese”

children selected on the basis of fat pads. J. Clin. Nutr.

1(6):453-468, 1953.

16 I Mellman, W. J., Bongiovanni, A. M., and Hope, J.

W.: The diagnostic usefulness of skeletal maturation in

an endocrine clinic. Pediatrics 23(3):530-544, Mar.

1959.

162Hortling, H., de la Chapelle, A., Frisk, M., and

Widholm, O.: The syndromes of obesity and of delayed

growth in adolescence. A eta Med. Stand.[Suppl. ]

412:109-122,1964.

16$ Markuske, H.: Rontgenologische Untersuchungen

der Handwurzelknocken adipkr Kinder. Z. Kinderheilkd. 106(3):225-234, 1969.

164Frisk, MO, Widholm, 0., Tenhunen, T., ‘ and

Hortling, H.: Overweight in adolescents–A complex

problem. Ann.Paedkitr.Fenn. 12(3):234-245, 1966.

165 Forbes, G. B.: Growth of the lean body mass

during childhood and adolescence. J.Pediatr.

64(6) :822-827, June 1964.

166Malcolm, L. A.: Growth and development of the

Bundi child of the New Guinea highlands. Hum.BioL

42:293-328, 1970.

167Allen, ‘I’., MacLeod, A. V., and Young, E. G.: On

the nutritional requirements of young children with

particular reference to calcification. Canad.J.M. Sc.

31(6):447-461, Dec. 1953.

168National Center for Health Statistics: Sample

design and estimation procedures for a national Health

Examination Survey of children. Vital and Health

Statistics, PHS Pub. No. 1000-Series 2-No. 43. Public

Health Service. Washington. U.S. Government Printing

Office, Aug. 1971.

169 National Center for Health statistics: Qmlity

control in a national Health Examination Survey. Vital,

and Health Statistics. PHS Pub. No. 1000-Series 2-No.

44. Public Health Service. Washington. U.S. Government

Printing Office, Feb. 1972.

1ToMoore, W. M.: Comparabilityy in skeletal maturation research. Am. J.Phys.AnthropoL 35:411-415, 1971.

171 Anderson, M., Hwang, S.-C., and Green, W. T.:

Growth of the normal trunk in boys and girls during the

second decade of life, related to age, maturity, and

ossification of the iliac epiphyses. J.Bone Joint Surg.

47 A:15541564, 1965.

172Gray, S. W., and Lamons, F. P.: Skeletal development and tooth eruption in Atlanta children. Am.J.-

Orthod. 45:272-277, 1959.

173Acheson, R. M., Fowler, G., Fry, E. I., Janes, M.,

Koski, K., Urbane, P., and van der Werff ten Bosch, J.

J.: Studies in the reliability of assessing skeletal maturity

from x-rays. Part 1, Greulich-Pyle Atlas. Hum.BioZ.

35:317-349, 1963.

174~dersen, E.: Skeletal maturation of Danish

school children in relation to height, sexual development, and social conditions. Acts Paediatr. Stand

(sup L) 185,1968.

1 f 5Mazess, R. B., and Cameron, J. R.: Skeletal

growth in school children: maturation and bone mass.

Am.J.Phys.Anthropol. 35:399-407, 1971.

176Mainland, D.: Evaluation of the skeletal age

method of estimating children’s development: II. Variable errors in the assessment of roentgenograms. Pediatrics 13:165-173, 1954.

177Anderson, M.: Growth, overgrowth, and maturity: observations based upon examination of serial

roentgenograms of children with hemihypertrophy.

Am.].Phys.AnthropoL 27:246,1967.

178Moed, G., Wight, B. W., and Vandegrift, H. N.:

Studies of physical disability: reliability of measurement

of skeletal age from hand films. Child Dev. 33:37-41,

1962.

179Johnston, F. E.: Skeletal age and its prediction in

Philadelphia children. Hum.Biol 35:192-201, 1963.

180 Sproul, A., and Pcritz, E.: Assessment of skeletal

age in short and tall children. Am. J.Phys.Anthropol.

35:433-439, 1971.

181 Demisch, A., and Watmam, p.: Calcfllcation of

mandibular third molar and its relation to skeletal and

chronological age in children. Child Dev. 27:459-473,

1956.

182Koski, K., Haataja, J., and Lappalainen, M.:

Skeletal development of hand and wrist in Finnish

children. Am. J. Phys.Anthropol. 19:379-382, 1961.

183 Hansman, C. F., and Maresh, M. M.: A longitudinal study of skeletal maturation. Am.J. Dis. Child.

101:305-321, 1961.

000

41
LIST OF DETAILED TABLES

Table 1. Mean, standard deviation, and standard error of the mean skeletal age (hand-wrist) of boys and girls, by rata

and chronological age at last birthday: United States, 1963-65 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2. Mean, standard deviation, and standard error of the mean skeletal age (hand-wrist) of boys and girls, by

geographic region and chronological age at last birthday: United States, 1963-55 . . . . . . . . . . . . . . . . . . . . .

3. Mean, standard deviation, and standard error of tha mean skeletal age (hand-wrist) of boys and girls, by annual

family income and chronological age at last birthday: United States, 1963-65 . . . . . . . . . . . . . . . . . . . . . . .

4. Mean and standard error of the mean skeletal age (hand-wrist) of white and Negro boys and girls, by geographic

region and chronological age at last birthday: United States, 1963-65 . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5. Mean and standard error of the mean skeletal age (hand-wrist) of white and Negro boys and girls, by annual

family income and chronological age at last birthday: United States, 1963-65 . . . . . . . . . . . . . . . . . . . . . . .

6. Mean skeletal age (hand-wrist) of boys and girls, by population size in urban areas and land use in rural areas of

residence and chronological age at last birthday, with selected standard errors: United States, 1963-65 . . . . . .

7. Mean skeletal age (hand-wrist) of boys and girls, by aducation of first parent and chronological age at last

birthday, with selected standard errors: United States, 1963-65 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8. Selected percentiles in the distribution of skeletal age (hand-wrist) for boys and girls, by race, geographic

region, annual family income, and chronological age at last birthday: United States, 1963-65 . . . . . . . . . . . . .

9. Mean bone-specific skeletal ages for the 31 individual hand-wrist bones of white and Negro boys and girls, by

chronological age at last birthday, with selected standard errors: United Statesr 1963-65 . . . . . . . . . . . . . . . .

10. Mean bone+ pecific skeletal ages for the 31 individual hand-wrist bones of boys and girls, by geographic region

and chronological age at last birthday, with selected standard errors: United States, 1963-65 . . . . . . . . . . . . .

11. Mean bone-specific skelatal ages for selected hand-wrist bones for boys and girls, by annual family income and

chronological aga at last birthday, with selected standard errors: United States, 1963-65 . . . . . . . . . . . . . . . .

12. Selected percentiles in the distribution of the individual child’s range in bone-specific skeletal ages for

radio-opaque (not adult) bones in the hand-wrist for white and Negro boys and girls, by chronological age at

last birthday :Unitad States, 1963-65 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

13. Selected percentiles in the distribution of the individual child’s range in bone-specific skeletal ages for the

radio-opaque (not adult) bones in the hand-wrist for boys and girls, by geographic region and chronological age

atlastbirthday: United States, 1963435 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

14. selected percentiles in the distribution of the individual child’s range in bone-specific skeletal agas for the

radio-opaque (not adult) bones in the hand-wrist for boys and girls, by annual family income and chronological

ageatlast birthday : United States, 1963-65 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

15. Median (chronological) age of onset of ossification in salected hand-wrist bones for boys and girls 6-11 years:

United States, 1963-65 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Page

43

44

45

46

48

49

50

51

53

59

67

70

70

71

71

42
Table 1. Mean, standard daviation, and standard error of the maan skeletal age (hand.wrist) of boys and girls, by race and chronological age at last birthday: United States, 1963-65

Standard of refarence, sex, and chronological age at

last birthday

Male standard

B~s

6years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10years, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Girls —

6years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7years, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9years . . . . .. o . . . . . . . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Ilyears m.. o . . . . . . . . . . . . . . . . . . . . . . . . . . .

Female equivalent

Girls —

6 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7years, d o . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

llyears . . .. o . . . . . . . . . . . . . . . . . . . . . . . . . .

Mala standard

Actual values

Boys: 6-n years . . . . . . . . . . . . . . . . . . . . . . . . . . .

Girls: 6-n years. .,....... . . . . . . . . . . . . . . . . .

Expacted valuas

Boys: 6.11 years. . . . . . . . . . . . . . . . . . . . . . . . . . .

Girls: 6-n years . . . . . . . . . . . . . . . . . . . . . . . . . . .

Whita Negro Other

Skelatal age in months

74.9

86.7

96.3

105.6

113.6

123.8

89.7

100.9

111.3

122.1

137.0

156.2

76.7

87.9

96.3

107.1

116.5

128.1

99.9

119.1

100.2

119.4

11.49

11.57

11.94

11.39

10.23

13.06

12.50

12.12

12.W

14.33

17.28

14.68

10.69

10.56

10.43

12.57

14.69

12.04

20.08

26.17

20.14

26.24

0.64

0.60

0.55

0.47

0.52

0.59

0.65

0.53

0.59

0.85

0.77

0.60

0.56

0.46

0.51

0.75

0.65

0.49

0.28

0.25

0.28

0.25

79.0

88.1

100.8

106.3

112.2

125.8

91.9

102.9

111.3

125.2

141.5

157.6

78.9

88.9

96.3

109.2

119.2

128.8

101.6

120.9

100,0

119.0

10.78

12.94

10.11

10.58

10.27

13.66

13.44

11.85

14.27

18.33

17.65

17.28

11.54

10.24

12.35

15.99

14,87

14.12

19.11

27.28

18.81

26.85

1.29

1.41

1.35

0.67

1.04

0.76

1.54

0.95

1.14

1.63

2.02

1.29

1.32

0.82

0.99

1.42

1.70

1.05

0.57

0.70

0.56

0.69

91.2

85.7

95.1

111.6

109.9

133.0

89.3

99.2

112.6

144.9

149.9

162.1

76.3

66.2

97.6

120.9

123.9

131.1

105.9

126.4

101.9

118.5

46.68

43.70

48.65

4.73

55.17

67.06

37.66

31.59

57.63

50.19

76.30 .

62.79

32.18

27.45

49.95

41.88

63.07

50.78

5.51

10.34

5.30

9.69

NOTE: X = mean skeletal age; Sy = standard deviation of skeletal age; and s= = standard error of mean. Expectad values remove

.. .

tha effect of differences in the chronological age distribution with respact to skeletal aga over the age (chronological) span 6-11 years

by indirect adjustment.

43
Table 2. Mean, standard deviation, and standard error of the mean skaletal age (hand-wrist) of boys and girls, by qeoma~hic raqion and

chronological age at last birthday: United States, 1963-65 - - - - -

Standard of refarence, sex,

and chronological

age at last birthday

Male standard

Boys

6 years . . . . . . . . . . . .

7 years . . . . . . . . . . . .

8years . . . . . . . . . . . .

9years . . . . . . . . . . . .

10years . . . . . . . . . . .

11 years . . . . . . . . . . .

Girls

6years . . . . . . . . . . . .

7years . . . . . . . . . . . .

8years . . . . . . . . . . . .

9years . . . . . . . . . . . .

10years . . . . . . . . . . .

11 years . . . . . . . . . . .

Female equivalent

Girls

6years . . . . . . . . . . . .

7years . . . . . . . . . . . .

8years . . . . . . . . . . . .

9years. ..m. .m . . . . .

10years . . . . . . . . . . .

11 years . . . . . . . . . . .

Male standard

Actual values

Boys: 6-11 years. . . . . . .

Girls: 6-11 years. . . . . . .

Expected values

Boys:6-llyears. . . . . . .

Girls:6-llyears. . . . . . .

Northeast Midwest South West

x

I

Sx s~ z Sx % z Sx % z Sx %?

Skaletal age in months

76.7

88.1

98.2

106.4

114.3

127.2

91.5

103.2

112.0

127.9

136.7

157.5

76.5

89.2

97.0

110.9

116.4

128.8

101.4

119.2

100.1

117.6

11.08

12.05

12.42

12,45

10.74

13.24

12.77

12.25

13.05

16.60

18.66

15.04

10.96

10.59

11.30

14.39

15.89

12.30

20.47

26.05

20.21

25.70

0.75

0.60

1.35

0.72

0.66

0.83

0.64

0.56

0.50

1.22

1.58

1.78

0.55

0.48

0.43

1,06

1.35

1.46

0.69

0.82

0.68

0.81

75.3

88.9

96.9

107.0

113.9

123.2

93.3

101.7

112.7

122.4

139.0

155.1

80.3

88.4

97.7

107.4

118.0

127.1

101.3

120.9

100.9

120.2

12.23

12.57

10.87

11.27

10.26

12.59

12.96

11.25

11.90

12.83

17,28

14.17

11.15

9.78

10.32

11.26

14.67

11.61

19.53

25.06

19.45

24.91

1.17

1.58

0.75

0.69

0.53

0.79

0.71

0.93

1.17

0.67

1.66

1.07

0.61

0.80

1.01

0.59

1.58

0.88

0.36

0.92

0.36

0.91

74.8

85.1

97.5

105.7

113.7

123.0

88.3

99.6

110.4

121.8

137.5

166.0

75.3

86.6

95.7

106.8

116.8

128.0

98.8

119.7

99.3

120.7

10.97

10.81

11.77

10.38

11.06

12.72

12.02

12.47

12.92

15.61

16.85

16.46

10.25

10.84

11.20

13.69

14.31

13.51

20.05

27.34

20.15

27.57

0.64

1.08

0.51

0.83

0.70

0.68

0.99

1.60

1.37

1.19

1.65

0.67

0.84

1.39

1.19

1.04

1.40

0.55

0.66

0.90

0.66

0.91

75.4

85.5

95.4

103.7

111.8

123.7

87.4

100.0

110.0

118.8

137.1

158.0

74.4

87.0

95.5

103.8

116.5

129.0

99.0

117.3

100.2

118.8

11.65

11.14

12.12

10.72

8.75

13.80

12.35

12.24

11.59

15.15

17.22

14.07

10.51

10.65

10.06

13.24

14.64

11.49

19,77

27.12

20.01

27.47

1.18

1.40

1.15

1.30

1.36

1.99

0.85

1.01

1.40

2,14

1.41

2.24

0.72

0.8B

1.22

1,87

1.20

1.83

1.29

1.06

1.31

1.07

NOTE: X=mean skeletal age; sx=standard deviatirm CIf skeletal age; andsz=standard error ofmean. Expected values remove the

..

effect of differences in the chronological age distribution with respect to skeletal age over the age (chronological) span 6-11 years by

indirect adjustment.
TabIe3. Mean, standard deviation, andstandard error of themean skeletal age(hand-wrist) of boYsand 9irls, bYannual familv income

Standard of reference, sex, and

chronological age

at last birthday

Male standard

Boys

6years . . . . . . . . . .

7years . . . . . . . . . .

8years . . . . . . . . . .

9years. .. o......

10years . . . . . . . . .

11 years . . . . . . . . .

Girls —

6years . . . . . . . . . .

7years . . . . . . . . . .

8yaars . . . . . . . . . .

9years . . . . ..o...

10years. . . . . . . . .

11 years . . . . . . . . .

Famale equivalent

Girls —

6years . . . . . . . . . .

7years . . . . . . . . . .

8years . . . . . . . . . .

9years . . . . . . . . . .

10years . . . . . . . . .

Ilyears. .. o.....

Male standard

Actual values

BoYs: 6-11 years. . .

Girls: 6-11 years, . .

Expected values

Boys: 6-n years. . .

Girls: 6-11 years. . .

,

andchronological ageat last birthday: United States, 1963-85

Lessthan $5,000 $5,000-$9,999 $10,000 or more

Lessthan $15,000

$3,000 or more

E 5X I

%

z Sx SF F Sx W x s~ F

I %

Skeletal age in months

75.1

85.9

86.7

104.3

112.9

124.9

90.0

100.9

110.3

120.4

137.7

158.3

77.0

87.9

95.6

105.4

116.8

128.2

99.1

118.4

99.6

119.0

11.50

12.14

12.08

11.04

10,52

14.00

13.26

12.74

11.30

15.19

17.95

15.43

11.34

11.10

9.79

13.30

15.23

12.66

20.42

26.41

20.52

26.54

0.77

1.21

0.62

1.18

0.80

0.85

0.81

1.22

0.69

0.63

1.63

1.19

0.69

1.06

0.60

0.55

1.38

0.98

0.66

0.79

0.66

0.79

76.6

87.6

96.9

106.2

114.4

123.6

90.4

101.2

112.5

124.1

137.2

156.9

77.4

8B.1

97.5

1OB.6

116.6

128.4

100.8

119.6

100.4

119.1

11.15

11.82

11.25

10.85

10.25

13.20

12.23

11.76

12.95

15.60

16.95

15.07

10.47

10.24

11.22

13.65

14.40

12.33

19.37

26.36

19.29

26.25

0.76

0.66

0.59

0.60

0.55

0.95

0.64

0.52

0.99

1.46

0.88

0.85

0.72

0.45

0.86

1.28

0.75

0.70

0.46

0.62

D.46

D.62

73.6

87.9

96.9

107.9

112.2

124.8

89.7

101.6

110.3

125.4

138.2

156.0

76.7

88.3

95.6

108.4

117.2

128.0

100.9

121.6

100.7

120.7

12.00

10.58

12.60

12.00

9.50

12.04

12.08

12.00

11.14

14.12

18.44

14.52

10.33

10.43

9.66

12.32

15.64

11.91

20.68

26.21

!0.66

Z6.23

1.58

1.14

1.43

1.11

0.77

1.05

1.34

1.68

1.51

2.17

1.82

1.63

1.15

1.46

1.31

1.89

1.54

1.34

0.97

0.99

0.97

0.99

73.4

85.1

96.5

102.5

112.5

124.5

90.4

101.5

107.9

120.4

138.5

156.2

77.4

88.2

93.9

105.4

117.5

128.1

98.3

118.5

99.6

119.1

1.21

2.42

0.92

1.41

1.14

1.49

0.93

1.30

1.07

1.10

1.89

1.50

0.80

1.13

0.93

0.96

1.60

1.23

1.08

1.09

1.09

1.10

74.3

87.2

97.6

107.8

113.9

125.8

91,6

107.2

110.7

124.8

141.5

158.8

78.6

93.2

95.8

108.9

119.2

129.4

100.1

123.8

100.5

121.4

1.46

1.99

4.72

3.54

1.93

2.54

3.77

2.92

2.28

1.86

3.83

3.48

3.24

2.54

1.97

1.62

3.23

2.64

2.17

2.02

2.18

1.98

NOTE: Yr=mean skeletal aga; sx ‘standard deviation of skeletal age; and sz=standard error of mean. Expected values remove the ..

effect of differences in the chronological age distribution with respect to skeletal age over the age (chronological) span 6-11 years by

indirect adjustment.

45
Table4. Mean and standard error of the mean skeletal age (hand-wrist) of white and Negro boys andgirls, bygeographic region and

chronological ageatlast birthday :United States, 1963-65

Standard of reference, sex, and chronological age

at last birthday

Male standard

Boys

6years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Girls —

6years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Female equivalent

GM

6years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Male standard

Actual values

Boys: 6-n years....,..,.. . . . . . . . . . . . . . . . . .

Girls: 6-n years . . . . . . . . . . . . . . . . . . . . . . . . . . .

Expected values

Boys: 6-n years . . . . . . . . . . . . . . . . . . . . . . . . . . .

Girls: 6-n years. ,, .,..... . . . . . . . . . . . . . . . . .

Northeast Midwest

White I Negro I White I Negro

Skeletal age in months

76.4

88.2

98.0

106.3

114.2

127.3

91.3

103.0

111.6

126.8

135.5

157.6

78.3

68.0

96.6

110.4

115.8

128.8

101.2

118.5

99.6

117.0

1.03

0.69

1.37

0.72

0.79

0.91

0.86

0.71

0.55

1.54

1.88

1.65

0.82

0.61

0.48

1.34

1.61

1.35

0.72

0.87

0.71

0.66

79.0

87.4

99.7

107.6

114.7

126.4

92.9

104.8

115.0

128.8

144.4

156.5

79.9

90.8

100.0

111.8

120.7

128.2

103.3

123.2

102.8

121.1

3.19

2.66

3.06

3.30

2.21

2.70

5.02

1.61

1.02

4.55

2.38

5.54

4.32

1.39

0.89

3.95

1.99

4.54

2.23

3.00

2.22

2.95

74.8

88.9

86.5

106.9

114.2

122.9

93.2

101.6

112.1

122.4

138.5

154.8

80.2

88.3

97.1

107.4

117.5

126.9

101,2

120.E

100,6

120.C

1.31

1.54

1.19

0.62

0.58

0.91

0.64

1.04

1.44

0.91

1.83

0.92

0.72

0.90

1,25

0.80

1.55

0.75

0.41

0.92

0.41

0,91

80.3

86.9

100,6

108.3

111.3

127.2

98.0

102.4

120.0

122.5

146.2

157.6

85.0

68.7

105.0

107.5

122.1

128.8

102.9

123.1

102.4

121.0

3.12

4.12

6.73

2.57

2.12

6.38

31.81

1.72

7.44

3.14

15.45

3,16

27.59

1.49

6.51

2.76

12.90

2.56

1.50

2.04

1.49

2.01

NOTE: ,7= mean skeletal age;Sz= standard error of maan. Expectad values ramova the effect of differences in the chronological age

distribution with respect to skeletal age over the aga (chronological) span 6-11 years by indirect adjustment.

46
Table4. Mean and standard error of the mean skeletal age (hand-wrist) of white and Negro boys and girls, bygeographic region and

chronological ageat last birthday: United States, 1963-65–Con.

Standard of raferenca, sex, and chronological age

at last birthday

Male standard

Boys

6 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8~cws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Girls —

6years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Ilyears . . . .. m........ . . . . . . . . . . . . . . . . .

Female equivalent

Girls —

6years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7yaars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Ilyears m. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Male standard

Actual values

Boys: 6-n years, .,..,.... . . . . . . . . . . . . . . . . .

Girls: 6-n years, . . . . . . . . . . . . . . . . . . . . . . . . . .

Expected values

Boys: 6-n years . . . . . . . . . . . . . . . . . . . . . . . . . . .

Girls: 6-n years, . . . . . . . . . . . . . . . . . . . . . . . . . .

South West

White I Negro I White I Negro

Skeletal age in months

73.4

83.5

95.8

105.9

114.5

122.3

87.3

98.4

111.1

120.4

136.6

155.4

74.3

85.4

96.1

105.4

116.3

127.4

98.1

119.5

99.1

120.8

1.41

1.30

0.62

1.23

0.93

0.62

1.30

1.67

1.68

1.87

2.14

0.85

1.11

1.45

1.45

1.64

1.82

0.70

0.96

1.15

0.97

1.16

79.2

89.0

101.0

105.2

110.8

124.9

90.6

103.0

108.4

125.6

139.9

157.6

77.6

89.0

94.4

109.6

118.4

128.8

100.6

120.5

100.9

121.4

1.96

2.33

0.59

0.45

2.26

1.97

1.78

2.07

1.95

2.62

3.15

0.92

1.52

1.79

1.70

2.29

2.67

0.75

1.11

1.64

1.11

1.85

75.0

85.7

95.0

103.3

111.7

123.3

87.0

100.0

110.4

118.6

136.7

157.8

74.0

87.0

95.7

103.6

116.4

128.9

98.7

117.3

99.9

118.6

1.12

1.54

1.27

1.31

1.46

1.96

0.76

0.84

1.31

2.11

1.20

2.08

0.65

0.73

1.14

1.84

1.02

1.70

1.16

1.11

1.17

1.12

77.4

83.8

101.5

110.3

113.9

126.1

89.1

100.1

105.4

122.2

139.4

160.5

76.1

87.1

91.4

107.2

118.2

130.2

101.2

115.8

101.4

118.5

24.70

26.63

5.34

42.79

5.79

40.23

28.82

9.24

2.55

1.09

44.27

5.29

24.62

8.04

2.21

0.96

37.54

4.29

3.66

4.66

3.57

4.77

NOTE: X= mean skeletal age; Sx = standard deviation of skeletal age; and Sx- = standard error Of mean. Expectedvaluas remove the

effect of differences in the chronological age distribution with respect to skeletal age over the age (chronological) span 6-11 years by

indirect adjustment.

47
Table 5. Mean and standard arror of the mean skeletal age(hand-wrist) of white and Negro boys and girls,by annual family incoma and chronological age at last birthday: Unitad States, 1863435

Standard of refarence,

sex, and chronolegicel

ageat last birthday

Male standard

gs

6years . . . . . . . . . . . . .

7years . . . . . . . . . . . . .

8yaars . . . . . . . . . . . . .

9yeare . . . . . . . . . . . . .

10yaars . . . . . . . . . . . .

11 years . . . . . . . . . . . .

GMs —

6years . . . . . . . . . . . . .

7years . . . . . . . . . . . . .

8yaars . . . . . . . . . . . . .

9years . . . . . . . . . . . . .

10years . . . . . . . . . . . .

11 years . . . . . . . . . . . .

Female aquivalant

@J

6yeara . . . . . . . . . . . . .

7yaars . . . . . . . . . . . . .

8years . . . . . . . . . . . . .

9years . . . . . . . . . . . . .

10years . . . . . . . . . . . .

11 years . . . . . . . . . . . .

Male standard

Actual valuas

Boys8-ll years. . . . . . . .

Girlx6-ll yeare . . . . . . . .

Expected values

80ys:&ll yeare . . . . . . . .

Girls:6-llyears. . . . . . . .

Lessthan $5,000 I

$5,000$9,999 I

$l0,000ormOre IUnder $3,000 1

$15,000 or more

White Negro White Negro

x %? x I

SE F

I

s~ F

I %

73.5

85.4

84.4

103.5

113.0

124.0

88.3

700.1

110.5

118,8

136.6

155.0

76.3

87.1

95.8

103.8

116.3

127.0

97.9

117.9

98.9

118.8

1.08

1.62

0.85

1.57

1.08

0.96

1.08

1.45

0.82

0.98

2.07

1.47

0.93

1.26

0.71

0.%

1.76

1.20

0.80

0.91

0.91

0.92

79.8

87.4

102.1

lm.5

112.7

127.3

91.6

102.9

108.7

124.8

140.9

160.0

78.6

68.9

95.4

108.4

118.9

130.0

102.2

119.6

89.5

117.3

1.59 76.4

1.82 87.3

0.89 86.9

1.33 10s.2

1.11 114.7

1.34 123.7

1.63 90.2

1.89 101.3

1.60 112.1

2,36 124.0

2.91 136.8

1.81 157.0

1.40 77.2

1.46 66.2

1.38 97.1

2.05 108.5

2.46 116.4

1.47 128.5

0.85 100.8

1.22 119.3

0.83 100.8

1.20 119.4

0.s3

0.74

0.69

0.62

0.54

0.92

0.85

0.62

0.97

1.54

0.93

0.86

0.73

0.54

0.84

1.35

0.79

0.70

0.64

0.63

0.54

0.63

77.6

92.0

95.7

105.7

110.0

122.0

86.0

101.4

115.9

127.0

141.6

155.1

83.0

88.2

100.9

110.5

119.3

127.1

100.2

123.9

100.5

121.9

1.68

3.81

4.37

1.81

1.50

2.08

2.33

1.84

3.67

3.34

3.78

2.79

2.01

1.69

3.20

2.91

3.18

2.28

1.74

2.04

1.75

2.01

Skeletal age in months

73.3

87.9

97.0

107.9

112.6

124.8

89.7

101.4

110.2

124.0

138.2

155.9

76.7

88.2

95.6

108.5

117.2

127.9

100.9

120.4

100.9

120.6

1.58

1.14

1.35

1.11

0.85

1.05

1.34

1.70

1.51

1.26

1.82

1.65

1.15

1.48

1.31

1.10

1.64

1.35

0.97

0.93

0.97

0.93

87.6

—

105.0

101.0

106.3

118.7

—

92.3

103.7

—

97.4

110.2

86.3

104.4

43.B7

-.

74.24

—

60.49

53.28

58.57

—

—

46.27

52.04

—

—

7.32

34.87

7.24

33.03

74.9

86.7

96.3

105.6

113.6

123.8

69.7

100.9

111.3

122.1

137.0

156.2

76.7

67.9

86.3

107.1

116.5

128.1

89.9

118.1

100.2

119.4

0.64

0.60

0.55

0.47

0.52

0.59

0.65

0.53

0.59

0.85

0.77

0.60

0.56

0.46

0.51

0.75

0.65

0.49

0.28

0.25

0.28

0.25

78.0

88.1

100.8

1C6.3

112.2

125.8

91.9

102.9

111.3

125.2

141.5

157.6

78.9

88.9

86.3

108.2

119.2

128.8

101.6

120.9

100.0

119.0

1.28

1.41

1.35

0.67

1.04

0.76

1.54

0.95

1.14

1.63

2.02

1.28

1.32

0.82

0.88

1.42

1.70

1.05

0.57

0.70

0.57

0.70

74.3

87.2

98.2

107.8

114.4

125.8

91.6

107.2

110.7

124.8

141.5

168.5

78.6

93.2

95.8

108.9

119.2

128.2

101.3

123.4

101.1

123.5

1.46

1.99

4.43

3.54

2.03

2.54

3.77

2.92

2.28

1.66

3.83

3.70

3.23

2.&l

1.97

1.62

3.23

3.02

2.12

1.88

2.12

1.89

—

—

—

—

—

—

—

—

—

—

—

—

—

—

—

—

—

—

—

—

—

NOTE: .? =meanskeletal age; s==stendard error of mean. Expectad values removatheeffactof dffarences intiechronoloQml a~dstrihtianwith re~wttoskeleW ~werthe W(chrMd@cdl

epan6-llyears byindirwtadjustm&t.
Table6. Mean skeletal age (hand-wrist) of boys andgirls, by population size in urban areas andland useinrumI areas ofresidence andchronological aXatlast

birthday, with selected standard errors: United States, 1963-65

Urbanized areas

Urban outside

urbanized areas

Urban

total

3 million

Less

1.0.2.9 250,000.

than

25,000 10,000. 2,500.

or more million 999,999

250,000 ‘r ‘ore

24,999 9,999

Rural-farm Rural-nonfarm

Standard of reference, sex, and

chronological age

at last birthday

Rural

total

r

10 acres

or more

Less

than

10

acres

Leas

than

10

acres

10 acrea

or more

Male standard Mean skeletal age in months

6 years . . . . . . . . . .

7years . . . . . . . . . .

Sears . . . . . . . . . .

9yeara . . . . . . . . . .

10years, . . . . . . . .

11 years . . . . . . . . .

G&

6years . . . . . . . . . .

7years, . . . . . . . . .

Sears., ..,.,...

9years,.,,,, . . . .

10years ...,..,..

11 years . . . . . . . . .

Female equivalent

Girls —

6years . . . . . . . . . .

7years.. .e, . . . . .

8years . . . . . . . . . .

9years . ...,.....

10years ...,.,...

11 years ..,..,...

Male standard

60YS —

6years ., ...,,...

11 years, .,,.,.,.

Glrla —

6years . . . . . . . . . .

11 years .,.......

Male standard

Actual mean

BOYS: 6-11 years . .

Girls: 6.11 years ,,

Expected mean

BoYs: 6.11 yeara . .

Girls: 6-11 yaars . .

73.8

86.6

97.7

108.6

111.6

123.1

89.9

99.7

109.4

121.3

140.1

158.7

76.9

86.7

95.2

108.3

118.6

129.4

2.17

1.12

2.62

3.13

74.2

85.6

98.4

104.1

113.8

122.5

90.8

98.2

107.6

122.2

138.5

157.4

77.8

85.2

93.6

107.2

117.5

72B.7

76.6

84.0

99.3

104.2

116.7

120.6

86.0

100.9

117.8

128.9

142.8

159.4

73.0

87.9

102.8

111.9

119.9

129.7

74.4

85.7

97.0

105.8

114.1

120.1

36.7

10+3.8

109.4

117.8

136.4

162.6

73.7

87.8

95.2

102.6

116.2

131.6

75.6

66.7

97.4

108.1

113,1

124.2

89.6

101.6

111.4

122,9

137.5

168.6

76.6

88,3

88.4

107,9

116.8

128.3

74.3

86.5

93.9

108.B

111.0

124.0

87.7

102,1

1C9.2

120.4

134.5

155.8

74.7

88.6

95.1

105.4

115.2

127.8

76.2

89.3

95.6

104.8

116.0

122.4

92.9

100.2

112.4

120.9

138.9

157.9

79.9

87.2

97.4

106.9

117.9

128.9

69.4

-.

103.0

118.0

153.0

80.0

S4.o

103.0

111.8

-.

159.3

66.0

71.0

89.0

96.8

-.

129.6

78.1

85.0

93.5

104.9

111.1

122.1

90.5

95.2

112.2

125.7

134.5

155.7

77.5

82.2

97.2

109.7

115.2

127.7

75.0

86.9

88.4

105.3

114.0

124.4

90.6

101.2

110.9

122.6

138.1

155.7

77.6

88.1

95.9

107.6

117.1

127.7

1.07

O.B1

1.05

1.32

99.5

118.9

99.7

118.9

0.89

0.52

77.3

87.5

98.6

106.6

113.4

126.8

B9.9

103.5

113.8

126.8

138.8

157.1

76.9

88.5

98.8

110.4

117.8

128.8

0.58

0.95

1.07

1.89

101.1

120.6

99.8

118.7

0.49

0.87

77.1

88.3

97.6

105.6

113.6

125,4

91.8

101.0

111.6

120.4

137.0

152,8

78.6

88.0

96.6

105.4

116.5

125.8

2.53

1.20

2.03

1.60

101.2

119.2

100.7

119.9

0.S3

1.24

75.1

67.4

95.9

105.2

114.0

124.1

91.0

100.5

111.3

122.6

137.9

158.1

78.0

87.5

86.3

107.6

116.9

128.0

Standard errmof the mean

0.69

0.71

0.77

0.86

100.3

119.3

100.2

119.3

--u0,34

0.43

1.23

1.62

2.76

2.72

99.3

119.0

100.4

120.7

__+

5.98 4.35 1.49 0.94

3.47 2.04 4.47 0.66

3.10 19.29 1.70 0.74

2.58 35.77 4.33 0.72

3.27 35.37

1.69 10B.18

2.73

2.47

5.87

8.34

3.28 56.56

2.04 79.80

100.1

121.0

90.9 101.8

108.8 121.3

100.4 100.3 100.5 9B. 1 99.8

119.2 116.0 122.8 117.4 119.5

100.6 101.0 100.6 99.0 99.9

119.2 117.0 120.2 118.7 119.5

Standard error of the mean

2.5B I

2.31 2.50 1.91 0.59

1.28 1.75 3.57 2.35 0.59

90.7 103.2

117.5 121.9

99.8

120.5

Boys: 6-11 yeara. .

Girls: 6.11 years . . EIEL-a49
Table7. Mean skeletal age (hand-wrist) of boys and girls, by education of first patent and chronological age at Iastbirthday, with

selected standard errors: United States, 1963-65

Standard of reference, sex, and ch ronological

age at last birthday

Male standard

Boys

6 years . . . . . . . . . . . . . . . . . . . . . . . . .

7 years . . . . . . . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . ...”.....

9years . . . . . . . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . . . . . . .

Girls —

6years . . . . . . . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . . . . . . .

Female equivalent

Girls

6 years . . . . . . . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . . . . . . .

Male standard

BOVS

6yaars . . . . . . . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . . . . . . .

Girls

6years . . . . . . . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . . . . . . .

Male standard

Actual mean

Boys: 6-n years . . . . . . . . . . . . . . . . . . . .

Girls: 6-llyears . . . . . . . . . . . . . . . . . . . .

Expected mean

Boys: 6-n years . . . . . . . . . . . . . . . . . . . .

Girls: 6-n years . . . . . . . . . . . . . . . . . . . .

Boys: 6-n years . . . . . . . . . . . . . . . . . . . .

Girls: 6-n years . . . . . . . . . . . . . . . . . . . .

Education of fi rst parent

Less than

5 years

72.5

83.7

96.2

103.8

112.6

122.0

88.6

98.4

107.8

120.0

139.1

154.1

75.6

85.4

93.8

105.0

118.0

I 26.6

3.21

2.13

3.30

2.77

99.3

118.7

101.3

120.4

I&l&_

75.8

82.5

97.2

105.1

112.9

126.7

87.3

101.1

110.7

120.5

136.0

1!%.3

74.3

88.0

95.8

105.5

116.0

128.2

2.05

1.91

1.90

2.35

100.6

120.3

100.9

121.4

9-11

years _&_l_E

Mean skeletal age in months

77.1

87.7

97.5

105.9

113.8

123.2

91.9

101.2

109.5

122.2

135.5

155.8

78.9

88.1

95.2

107.2

115.8

127.8

74.6

87.1

97.6

105.5

113.5

122.7

89.0

100.8

112.8

123.4

137.9

157.9

76.0

87.8

97.8

108.2

116.9

128.9

76.4

87.3

95.5

105.9

113.7

123.7

90.8

101.4

111.6

122.8

138.7

155.2

77.8

88.2

96.6

107.8

117.7

127.2

75.3

89.3

99.1

107.1

114.5

127.8

90.4

104.6

113.5

124.8

133.4

158.2

77.4

90.6

98.5

108.9

114.4

129.1

Standard error of tha mean

1.40 1.14 0.64 2.44

2.09 1.10 0.83 1.89

1.38 1.82 0.69 1.34

1.73 1.43 1.17 2.47

Mean skeletal age in months

102.7

120.9

102.3

121.5

99.0

119.2

99.3

118.9

99.4

119.3

99.4

119.1

102.1

116.0

100.3

115.2

16 170rmore

yaars years

77.1

89.4

96.3

107.5

113.0

124.7

92.5

98.5

112.2

124.3

143.6

158.1

79.5

85.5

97.2

108.6

120.3

129.0

1.84

1.74

2.43

1.76

100.6

121.8

99.6

120.4

Standard error of the mean

1.15 1.54 0.84 0.73 0.50 1.16 0.79

2.05 1.29 1.17 0.89 0.80 1.50 1.30

74.1

64.4

99.3

105.2

112.4

126.8

86.3

103.8

109.4

126.0

137.9

159.6

73.3

89.8

95.2

110,0

116.9

129.8

1.47

1.83

2.76

2.52

101.9

119.4

101.7

118.8

1.03

1.84

50
Table8, Selected percentiles in the distribution of skeletel age (hand-wrist) for boys and girls, by race, geographic region, annual

family income, and chronological age at last birthday: United Statas, 1963-65

Rece, region, annual family income, and percentile

Whita

75 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

50 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

25 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Negro

75 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

50 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

25 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Northeast

75 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

60 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

25, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Midwest

75 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

50 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .’ . . . . . . . . . . . .

25 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

75 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

50 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

25 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

West

75 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

60, . ., .,, ,, ., . .,.,,.... . . . . . . . . . . . . . . . . . . . . . . . .

25 ...,..,,,...,....,., . . . . . . . . . . . . . . . . . . . . . . . . .

Lassthan $5,000

75, ,,, ,,, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

50. . ., !, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

25 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$5,000-$9,999

75 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

50, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

25 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$10,000 or more

75 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

50 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

25, .,, ,,, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Chronological age in years at last birthday

Boys

&l&l&l&

82.S

75.1

67.E

85.[

79.~

72.4

84.4

77.2

69.E

85.C

76.3

67.3

81.9

74.3

69.3

83.5

75.5

68.1

83.9

74.6

69.1

84.3

76.7

68.7

82.4

74.9

67.3

84.9

86.8

79.1

95.0

88.2

79.2

97.6

87.5

79.8

98.9

87.3

81.9

91.8

87.4

77.5

94.3

66.0

78.3

94.0

86.6

77.5

96.4

87.2

79.7

94.6

88,0

81.7

10 I11

years years

Skeletal age in months

1%.6

97.6

88.9

108.5

105.1

93.3

108.4

99.2

89.7

105.9

98.4

89.7

107.8

98.5

90.7

106.2

86.7

88.6

107.3

97.9

89.8

107.0

98.1

89.2

106.9

99.3

89.7

113.6

107.6

98.7

114.9

107.9

99.1

115.2

109.4

98.5

114.9

10B.9

101.8

112.6

107.4

99.1

111.6

105.0

96.1

111.7

106.2

97.0

114.4

108.1

99.7

-,

114.8

108.5

103.4

120.3

113.7

108.4

118.8

112.6

107.6

121.8

113.9

108.8

120.4

114.3

108.4

121.4

113.8

107.8

116.5

112.7

108.1

120.3

113.1

107.8

120.6

114.1

109.0

118.1

112.5

106.5

131.2

121.0

115.2

133.3

123.9

117.1

134.3

125.0

118.2

129.9

123.0

114.7

129.3

121.4

114.6

131.5

119.6

115.4

133.8

123.0

115.6

130.4

120.7

115.4

131.0

123.0

117.2

51
Table8. Selected percentiles in the distribution of skeletal age (hand-wrist) for boys andgirls, by race, geographic region, annual

family income, and chronological age at last birthday: United States, 1963-65–Con.

Race, region, annual

family income, and

percentile

White

75 . . . . . . . . . . . . .

50 . . . . . . . . . . . . .

25 . . . . . . . . . . . . .

Negro

75 . . . . . . . . . . . . .

50 . . . . . . . . . . . . .

25 . . . . . . . . . . . . .

Northeast

75 . . . . . . . . . . . . .

50 . . . . . . . . . . . . .

25 . . . . . . . . . . . . .

Midwest

75 . . . . . . . . . . . . .

50 . . . . . . . . . . . . .

25 . . . . . . . . . . . . .

South

75 . . . . . . . . . . . . .

50 . . . . . . . . . . . . .

25 . . . . . . . . . . . . .

Wast

75 . . . . . . . . . . . . .

50 . . . . . . . . . . . . .

25 . . . . . . . . . . . . .

Lessthan $5.000

75 . . . . . . . . . . . . .

50 . . . . . . . . . . . . .

25 . . . . . . . . . . . . .

$5,000-$9,999

75 . . . . . . . . . . . . .

50 . . . . . . . . . . . . .

25. . . . . . . . . . . . .

$10,000 or more

75 . . . . . . . . . . . . .

50 . . . . . . . . . . . . .

25. . . . . . . . . . . . .

52

Chronological age in years at last birthday

Girls (male standard) Girls (female equivalent)

6 7 8 9 10 11 6 7 8 9 10 11

years years years years years years years years years years years years

Skeletal age in months

98.6

89.4

81.6

102.8

93.1

83.0

99.0

91.5

82.5

104.7

93.3

83.6

97.2

88,9

80.3

96.4

88.2

80,4

100.8

89,4

80.9

98.5

91.0

82.3

97.7

89.6

81.4

110.6

103.6

92.6

113.0

106.8

93.3

112.4

106.5

86.1

110.4

104.2

93.3

110.6

103.1

90.4

109.7

99.7

91.2

110.5

104.4

91.6

111.2

103.7

93.5

112.3

105.5

91.5

118.1

112.6

106.4

117.4

111.2

106.1

118.4

112.8

107.5

119.6

114.2

107.3

116.0

110.3

104.6

118.8

111.5

103.9

117.6

111.2

104.8

118.6

113.2

107.1

117.2

112.4

106.3

129.3

119.9

114.2

131.8

121.0

115.9

138.4

123.9

117.0

128.4

120.4

115.4

128.9

119.4

113.4

126.6

117.1

111.8

127.4

118.4

112.9

131.3

121.1

114.7

131.6

123.8

116.0

152.9

135.3

124.0

156.8

141.5

127.1

154.1

135.3

122.7

153.5

141.2

125.8

154.5

135.0

124.8

152.4

134.2

123.4

154.2

136.3

122.5

153.0

134.1

124.9

153.9

138.3

127.1

166.5

159.5

149.4

170.6

160.5

148.0

166.5

160.5

150.6

166.0

158.6

145.0

166.9

160.1

146.0

168.1

160.3

150.7

167.1

160.2

148.6

167.6

159.8

149.2

166.5

158.4

149.0

B5.6

76.4

57.6

B8.9

80.1

69.5

86.0

78.5

68.8

90.7

80.3

70.4

64.2

75.9

66.3

83.4

73.2

66.4

87.8

76.4

66.9

B5.5

78.0

68.4

64.7

76.6

67.4

95.8

89.6

79.6

98.0

92.8

80.3

97.4

92.5

83.1

95.7

90.2

80.3

95.8

89.1

77.4

95.4

66.7

78.2

95.8

90.4

78.6

86.2

89.7

80.5

97.3

91.5

78.5

103.1

97.6

92.4

102.4

96.2

92.1

103.4

97.8

93.5

104.6

99.2

93.3

101.0

95.6

90.6

103.8

86.5

89.9

102.6

96.2

90.8

103.6

98.2

93.1

102.2

97.4

92.3

112.2

104.9

99.2

113.4

106.0

100.9

117.4

108.4

102.0

111.4

105.4

100.4

111.9

104.4

98.4

110.3

102.1

96.8

110.7

103.4

97.9

113.2

106.1

99.7

113.3

108.4

101.0

125.9

115.6

108.5

128.4

119.2

110.6

126.6

115.6

107.7

126.2

119.1

109.8

126.8

115.5

108.9

125.4

115.1

108.2

126.6

116.2

107.5

126.0

115.0

108.9

126.4

117.3

110,6

134.8

129.8

123.7

138.6

130.2

123.0

134.8

130.2

124.3

134.5

129.3

121.0

134.9

130.0

122.0

136.1

130.2

124.4

135.1

130.1

123.3

135.6

129.9

123.6

134.8

129.2

123.5
Table9. Mean bone-specific skeletal ages forthe31 individual hand-wrist bones of white and Negro boysand girls, by chronological

ageatlast birthday, with selected standard errors: United States, 1963-65

Standard of reference, sex, and

chronological age at last birthday

Male standard

Boys

6years . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . .

10years . .. m. . . . . . . . . . . . . . .

ll~ears, . .. m. . . . . . . . . . . . . .

Girls —

6years . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . .

9yaars . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . .

Female equivalent

Girls —

6years . . . . . . . . . . . . . . . . . . .

7years . m. . . . . . . . . . . . . . . . .

Byears . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . .

10years . . . . .. m....... . . . . .

11 years . . . . . . . . . . . . . . . . . . .

Male standard

Boys

6years . . . . . . . . . . . . . . . . . . .

Ilyears ..m. d o........ . . . . .

Girls —

6years . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . .

Actual values

Boys: 6-n years . . . . . . . . . . . . . .

Girls: 6-llyears . . . . . . . . . . . . . .

Expected values

Boys: &ll years . . . . . . . . . . . . . .

Girls: 6-n years . . . . . . . . . . . . . .

8oys:6-ll years . . . . . . . . . . . . . .

Girls: 6-llyears . . . . . . . . . . . . . .

Radius I Ulna I Capitate I tiarnate I Triquetral

White I Negro I White I Negro I White I Negro I White I Negro I White I Negro

74.1

85.2

94.9

105.8

113.9

123.8

84.7

96.6

107.9

118.1

133.4

153.8

76.8

87.8

94.9

103.1

114.4

126.9

0.7!5

0.55

0.71

0.63

99.3

115.3

99.8

115.9

0.30

0.26

79.7

87.9

100.2

108.8

112.9

126.4

89.3

100.6

109.8

124.0

139.4

156.4

BI .3

91.3

95.9

108.0

118.0

128.7

2.06

0.82

2.15

1.05

102.2

119.0

99.6

115.5

0.76

0.98

85.1

90.9

96.8

104.9

113.1

123.1

89.6

98.0

107.0

118.3

132.3

151.2

66.3

87.9

93.0

103.3

113.0

125.2

0.74

0.61

0.54

0.55

105.9

117.2

106.2

117.8

Mean skeletal age in months

89.1

92.9

100.1

10B.O

110.4

125.2

95.6

101.1

108.2

122.8

137.5

164.2

87.6

88.3

94.1

107.4

116.5

127.2

75.3

66.1

95.4

104.8

114.2

124.2

87.1

98.8

109.9

120.0

135.7

154.3

75.1

85.8

95.9

105.0

115.8

127.3

BO.9

88.3

101.1

108.6

114.1

126.9

92.4

104.1

111.2

124.8

141.1

155.3

80.4

90.1

96.6

108.B

119.6

128.2

Standard error of the mean

2.31

0.82

1.69

1.52

0.69

0.69

0.68

0.79

1.65

0.73

1.90

1.37

74.9

85.4

94.6

104.2

114.4

125.3

86.4

98.7

109.9

121.6

137.6

154.8

74.4

85.0

95.9

106.6

116.8

127.8

0.65

0.68

0.55

0.63

Mean skeletal age in months

106.7 99.7 102.9 99.5

120.9 116.8 120.1 117.4

105.3 100.2 100.0 100.1

117.7 117.4 116.B 118.2

Standard error of the mean

81.8

88.3

101.5

109.2

115.2

129.0

93.5

104.7

111.7

127.2

143.7

157.6

BO.8

90.7

97.4

110.2

120.8

129.6

1.70

0.99

1.88

1.27

103.7

121.7

100.0

117.5

73.1

85.6

96.2

106.1

114.3

123.7

BB.8

101.3

110.9

120.3

133.3

150.2

75.8

87.3

95.9

105.2

114.3

124.6

1.07

0.55

0.61

0.65

99.7

116.4

100.2

117.0

7B.2

89.7

102.6

110.0

114.2

126.1

94.7

105.8

112.1

124.2

138.6

152.0

81.7

91.8

97.1

107.2

117.6

125.5

3.11

1.05

1.87

1.61

103.2

119.8

100.0

116.5

53
Table9. Mean bone-specific skeletal ages forthe31 individual hand-wrist bones of white and Negro boy~and girls, by chronological

age at Iastbirthday, with selected standard errors: United States, 1963-65-Con.

Lunate Scaphoid Trapezium I Trapezoid I Metacarpal 1

Standard of reference, sex, and

chronological age at last birthday

White I Negro I White I Negro I White ] Negrol White I Negro I White I Negro

73.1

82.9

98.8

107.4

114.7

127.7

87.9

101.0

110.0

125.4

138.3

153.0

72.9

91.5

98.6

110.2

117.3

126.5

2.28

1.29

2.44

1.56

Male standard

BOYS Mean skeletal age in months

6years . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . .

87.8

92.8

103.6

108.9

114.1

128.0

99.8

107.0

111.7

125.4

138.5

151.2

82.9

92.0

86.7

108.4

117.5

125.1

76.7

82.9

91.4

101.3

109.6

120.9

88.5

98.6

108.9

118.0

132.4

151.6

82.2

86.3

94.9

103.0

113.7

125.3

77.3

85.6

98.6

105.0

111.9

124.8

93.3

104.4

111.0

124.0

138.2

153.2

84.4

90.7

86.5

108.0

117.1

126.2

79.8

87.7

86.2

105.8

113.2

122.6

90.0

101.3

110.2

119.2

132.8

150.6

77.0

89.3

95.6

104.2

113.9

124.8

69.7

82.7

94.1

105.1

114.5

124.7

84.6

96.9

109.0

119.2

132.9

150.4

69.6

84.9

98.4

104.2

113.9

124.7

1.05

0.64

1.00

0.70

98.8

114.8

99.1

115.4

0.38

0.26

82.6

90.6

98.4

I(M.4

114.1

123.5

93.4

102.7

111.6

120.0

132.4

150.1

76.4

85.8

85.6

104.0

113.2

124.6

84.8

89.6

101.8

108.0

112.5

126.0

95.0

106.2

111.9

123.5

136.5

152.3

83.0

92.2

86.9

107.8

116.2

126.3

1.06

0.78

1.56

1.55

105.0

119.8

102,6

116.7

0.60

0.67

70.6

83.3

93.2

104.0

111.8

122.6

89.6

101.0

110.7

121.5

126.3

155.3

74.6

66.0

86.8

106.5

116.2

128,2

0.78

0.63

0.71

0,68

97.3

118.6

97.9

119.2

0.27

0.26

78.6

66.1

100,9

105.7

112.4

125.7

86.6

105.9

112.9

125,8

141.6

155.5

81.6

91.9

98.9

109.4

120.3

128,2

1.51

0.79

1.64

2.05

101.2

122.0

97.7

118.6

0.66

0.68

Girls .

6years . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . .

l~vears . . . . . . . . . . . . . . . . . . .

Female equivalent

Girls

6years . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . .

Male standard

Boys

6years . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . .

Standard error of the mean

1.16

1.19

0.70

0.74

1.67

0.66

0.47

0.51 0.60

0.57

0.68

Girls

6years . . . . . . . . . . . . . . . . . . .

11 years, . . . . . . . . . . . . . . . ,.,

1.48

1.52

0.68

0.69

2.01

1.37

0.45

0.72

Actual values

8oys:6-ll years . . . . . . . . . . . . . .

Girls: 6-llyears . . . . . . . . . . . . . .

Mean skeletal age in months

107.1

121.6

99.6

115.9

102.1

119.6

102.7

116.8

100.8 104.5

118.0 118.1

98.8 105.0

114.8 118.7

Ex~ected values

Boys: 6-n years . . . . . . . . . . . . . .

Girls: 6-llyears . . . . . . . . . . . . . .

104.2

118.3

100.2

116.6

99.1

115.9

103.1

117.4

Standard error of the mean

0.84 0.35 0.71 0.29

0.49 0.22 0.65 0.21

Boys: 6-n years . . . . . . . . . . . . . .

Girls: 6-n years . . . . . . . . . . . . . .

0.86

0.78

0.25

0.18

54
Table9. Mean bone-specific skeletal ages forthe31 individual hand-wrist bones of white and Nemo bovsand airis. bvchronolcmical

-. -.

ageat last birthday, with selected standard errors: United States, ?963-65–Con.

Metacarpal II Metacarpal Ill Metacarpal IV Metacarpal V

Whita Nagro White Negro White Negro White Negro

Standard of reference, sex, and

chronological age at last birthday

Pisiform

Mala standard

Bovs Mean skeletal age in months

73.0

85.5

94.4

104.7

112.1

122.2

88.7

100.8

110.1

120.7

135.6

154.9

73.7

85.9

95.1

105.7

115.8

127.9

80.6

88.1

100.8

105.7

112.5

125.4

92.3

104.0

112.1

126.2

142.6

156.3

77.3

90.0

97.1

109.6

119.8

128.6

72.5

85.2

84.5

104.6

112.1

?22.6

88.7

100.4

110.0

121.3

137.2

156.3

73.7

85.4

95.0

106.2

116.2

128.6

6years . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . .

74.2

86.1

~.$

105.1

112.7

122.4

89.2

101.3

110.6

120.7

135.0

153.9

74.2

66.3

95.6

105.7

115.5

127.4

0.86

0.52

0.73

0.69

99.0

118.0

99.4

118.5

0.32

0.24

80.2

87.6

100.7

106.2

112.1

124.7

92.4

104.2

111.9

125.6

141.8

155.3

77.4

89.8

96.9

109.3

119.4

128.2

1.75

0.95

1.99

1.27

73.9

85.9

94.8

104.9

112.4

?22.7

89.2

101.2

110.5

120.8

135.8

154.8

74.6

87.2

96.5

105.8

115.8

127.9

0.88

0.54

0.75

0.68

80.5

87.8

100.7

106.1

112.5

125.4

92.2

104.0

112.1

126.0

142.5

156.2

78.2

90.0

98.1

110.0

120.2

128.6

80.3

88.7

100.8

105.6

112.6

125.5

91.6

103.9

112.5

126.4

143.3

157.0

76.6

88.9

97.5

109.4

119.8

129.0

2.14

0.79

2.22

1.29

175.0

112.1

115.7

117.5

119.2

126.9

116.6

117.1

119.7

125.4

137.9

153.9

102.8

703.1

104.8

109.4

116.9

126.9

81.31

0.72

1.96

o.6~

122.5

134.7

122.5

135.0

134.0

113.8

114.4

117.0

117.0

126.0

116.7

116.5

123.5

129.7

141.4

153.3

102.8

102.8

107.8

111.8

119.2

126.6

94.75

2.03

26.18

2.29

121.9

138.0

122.8

136.1

Girls —

6years . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . .

10years, . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . .

‘male equivalent

Girls —

6years . . . . . . . . . . . . . . . . . . .

7yaars . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . .

9yaars . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . .

Male standard

Boys Standard error of the n

1.77 0.83

I

1.74

0.82 0.52 0.80

6years . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . .

0.84

0.61

1.92 0.69 2.05

1.40 0,72 1.37

Girls —

6years . . . . . . . . . . . . . . . . . . .

1~ years . . . . . . . . . . . . . . . . . . .

0.76

0.67

Actual values Mean skeletal age in months

101.5

121.0

98.8

118.3

101.8

121.2

98.4 101.8

118.0 121.3

98.3

118.5

101.9

121.5

130ys:6-ll years . . . . . . . . . . . . . .

Girls: 6-llyears . . . . . . . . . . . . . .

Expected values

Boys: 6-n years . . . . . . . . . . . . . .

Girls: 6.11 years . . . . . . . . . . . . . .

99.2

118.1

99.3

118.8

99.1

118.4

98.9 98.7

118.6 118.1

98.8

119.0

98.7

118.5

Standard error of the mean

0.67 0.31 0.68 0.32 0.73

0.76 0.23 0.82 0.25 0.85

Boys: 6-llyeara . . . . . . . . . . . . . .

Girls: 6-n years, . . . . . . . . . . . . .

0.72 0.31

0.79 0.25

0.45 1.32

0.40 1.39

55
Table9. Mean bone-spacific skeletal ages forthe31 individual hand-wrist bones of white and Negro boys andgirls, by chronological

age at last birthday, with selected standard errors: United States, 1963-65-Con.

Standard of reference, sex, and

chronological ageat last birthday

Male standard

Boys

6years . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . .

Girls —

6years . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . .

Female equivalent

Girls —

6years . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . .

Male standard

Boys

6years . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . .

Girls

6years . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . .

Actual values

Boys: 6-llyears . . . . . . . . . . . . . .

Girls: 6-n years . . . . . . . . . . . . . .

Expected values

Boys: 6-llyears . . . . . . . . . . . . . .

Girls: 6-llyears . . . . . . . . . . . . . .

8oys:6-ll years . . . . . . . . . . . . . .

Girls:6-llyears . . . . . . . . . . . . . .

Adductm

sesamoid

==1=

-.

.-

--

155.0

157.5

156.1

152.0

154.6

154.6

155.6

158.2

162.4

125.5

127.6

127.6

128.3

130.8

132.4

-.

0.63

107.46

0.31

156.1

160.2

156.6

160.7

0.51

0.27

...

-.

-.

--

164.0

159.2

.-

-.

154.6

160.3

159.6

165.7

-.

127.6

131.2

130.8

134.4

—

3.21

1.27

159.5

162.5

156.7

160.3

2.98

0.71

Flexor

sesamoid

+

...

...

-.

159.6

158.0

161.5

-.

160.0

160.7

161.2

161.8

165.3

-.

131.0

131.4

131.6

131.9

134.2

-.

1.26

-.

0.44

161.1

164.0

160.7

164.4

1.16

0.39

Maan skeleteI age in months

-.

...

-.

-.

--

158.2

-.

-.

158.0

162.0

163.5

168.5

-.

-.

130.0

132.0

133.2

136.5

76.0

87.2

96.3

105.1

113.6

124.3

89.8

100.6

112.6

125.8

141.1

160.3

74.9

85.6

98.6

108.4

119.0

130.6

Standard erro

... 0.68

0.17 0.74

0.69

1.42 0.69

78.9

88.4

99.1

103.9

110.8

126.7

90.4

101.9

113.4

128.8

146.2

161.4

75.4

86.9

99.4

111.8

122.1

131.4

78.6

90.1

98.8

107.3

114.8

124.9

92.7

103.6

114.1

125.6

141.1

160.5

77.7

88.6

99.1

108.6

119.1

130.8

of the mean

1.13 0.67

1.20 0.68

1.73 0.78

2.05 0.64

Mean skeletal age in months

158.2 100.2 100.9 102.2

166.0 121.2 122.5 122.4

161.0 100.3

I

100.1 102.0

164.2 121.5 120.8 122.4

Standard error of the mean

0.17 0.36 0.38 0.32

1.13 0.36 0.93 0.35

79.4

88.0

99.4

103.4

110.7

125.8

91.1

102.3

112.1

125.9

144.8

159.9

76,1

87.3

97.1

108.9

121.4

130.4

1.25

1.24

1.67

1.71

100.7

121.6

101.8

121.9

0.52

0.80

Proximel

phalanxlll

-o

78.1

89.4

98.4

107.0

114.9

125.0

92.1

103.2

113.9

125.6

141.3

160.6

77.1

88.2

98.9

109.3

119.2

132.6

0.69

0.70

0.81

0.63

101.9

122.3

101.7

122.3

0.33

0.36

78.3

87.3

99.1

103.7

110.7

125,4

91.2

102,0

112.3

125.7

145.3

160.2

76.2

87.0

97.3

109.4

121.6

132.2

1.20

1.26

1.75

1.82

100.3

121.7

101.6

121.7

0.52

0.84

56
Table9, Mean bone-specific skeletal ages forthe31 individual hand-wrist bones of white and Negro boys andgirls, by chronological

age at Iastbirthday, with selected standard errors: Unitad States, 1963-65-Con.

Standard of reference, sex, and

chronological age at last birthday

Male standard

Boys

6years . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . .

8yeers . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . .

10years d o . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . .

Girls —

6years . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . .

Female equivalent

Girls —

6years . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . .

11 yeara . . . . . . . . . . . . . . . . . . .

Male standard

8oys

6yaars . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . .

Girls

6yaers . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . .

Actual values

Boys: 6-llyears . . . . . . . . . . . . . .

Girls: 6-n years . . . . . . . . . . . . . .

Expectadvalues

Boys: 6-llyaers . . . . . . . . . . . . . .

Girls: 6-llyaera . . . . . . . . . . . . . .

Boys: 6-llyears . . . . . . . . . . . . . .

Girls: 6-n years . . . . . . . . . . . . . .

Yhite

I

Nagro White Negro

77.2

89.3

9B.4

107.1

I15.5

125.6

91.8

I03.3

114.3

126.0

141.4

I60.8

76.8

88.3

99.3

I09.5

119.2

132.8

0.74

0.70

0.82

0.70

01.9

22.4

01.7

22.4

0.37

0.37

77.5

86.8

99.0

103.7

111.9

125.6

91.0

102.1

112.2

125.9

145.3

160.6

76.0

87.1

97.2

109.4

121.6

132.6

1.40

1.15

1.68

1.79

100.3

121.7

101.5

121.8

0.55

0.86

77.7

89.8

99.0

107.2

115.4

125.7

92.2

103.4

114.6

126.1

141.6

160.9

77.2

88.4

100.6

109.6

119.5

131.4

1 1

Middle Middle Middle

phalanx I I phalanx Ill phalanxlV

White Negro White Negro White Negro

Mean skeletal aga in months

78.4

88.1

100.0

105.0

112.1

127.0

91.9

102.4

113.2

127.0

145.8

160.6

76.9

87.4

99.2

110.0

121.6

131.3

80.7

91.4

99.9

108.4

115.8

126.6

93.8

103.5

114.6

126.0

141.3

160.1

78.8

89.5

100.4

109.5

119.2

131.0

81.3

90.7

102.7

106.8

113.2

127.1

93.2

103.3

113.1

126.9

143.7

160.5

78.2

89.3

98.2

109.9

120.7

131.2

78.9

89.7

98.8

107.7

115.3

126.2

92.4

102.6

113.7

125.6

141.0

160.0

77.7

88.6

99.4

109.3

119.0

131.0

Standard error of the mean

0.76 1.60 0.59

0.66 1.37 0.60

0.83 2.05 I

0.80

0.64 1.83 0.70

102.2

122.6

102.1

122.6

1.17 0.63

0.93 0.63

1.50 0.76

2.09 0.70

Mean skeletal age in months

101.3 103.5 103.2 102.5

122.4 122.7 122.4 122.1

101.9 103.6 103.3 102.6

122.1 122.8 122.3 122.2

Standard error of the mean

0.37 0.71

I

0.28 0.66 0.29

0.34 0.91 0.30 0.92 0.30

80.3

89.8

101.6

106.2

112.8

127.4

92.0

102.7

112.1

126.2

143.7

160.9

77.5

88.7

97.1

109.6

120.7

131.3

79.2

90.7

99.4

107.4

114.9

125.2

93.0

102.8

113.3

124.7

140.0

159.4

78.0

88.8

98.6

108.7

118.5

130.7

1.33 0.64

0.86 0.61

1.57 0.73

1.75 0.75

102.5 102.6

121.9 121.7

102.3 102.6

121.7 121.8

81.3

89.9

102.1

107.0

112.1

125.9

92.4

102.7

111.7

125.6

142.4

160.4

77.7

68.7

96.7

109.3

119.1

131.7

1.39

0.98

1.55

1.73

102.6

121.5

102.4

121.3

0.52 0.30 0.57

0.92 0.33 0.93

57
Table9. Mean bone-specific skeletal ages forthe31 individual hand-wrist bones of white and Negro boysand girls, by chronological

age at last birthday, with selected standard errors: United States, 1963-65-Con.

Middle

phalanx V

G

Distal Distal Distal Distal Distal

phalanx I phalanx II phalanx Ill phalanxlV phalanx V

White Negro White Negro White Negro White Nagro White Negro

Standard of reference,

sex, and chronological

age at last birthday

Male standard

Boys

6yaars . . . . . . . . .

7 years . . . . . . . . .

8years . . . . . . . . .

9 years . . . . . . . . .

10 years . . . . . . . .

11 years . . . . . . . .

Mean skeletal aga in months

76.3

89.2

99.7

108.2

115.5

125.2

93.3

103.9

112.8

123.6

138.0

157.3

78.3

88.9

97.8

107.8

117.0

129.3

81.0

92.9

105.0

108.5

113.2

126.0

94.5

104.6

113.0

124.8

138.7

156.2

79.5

89.6

98.0

108.8

117.7

128.6

75.5

88.9

99.4

108.1

115.6

125.3

92.8

103.6

112.8

123.5

138.2

157.4

78.7

89.9

98.8

107.8

117.2

129.4

78.7

90.3

99.3

107.7

115.2

125.8

93.4

103.0

113.7

125.2

140.5

160.0

74.8

89.0

98.7

108.2

118.5

130.6

79.8

89.2

102.8

107.2

112.2

127.0

92.6

102.4

111.7

125.5

142.6

160.8

74.3

88.4

96.7

108.5

119.8

130.9

73.9

86.9

98.7

107.7

115.2

125.6

90.9

102.2

113.2

124.6

139.6

158.8

74.9

87.2

98.2

107.8

117.8

130.4

75.7

88.9

101.6

106.9

112.5

127.2

91.0

102.0

112.0

126.1

141.5

157.6

75.0

87.0

97.0

109.1

119.2

129.6

80.7

92.5

104.9

108.7

113.3

126.3

84.1

104.4

112.1

125.4

139.8

156.6

80.1

91.2

98.1

109.4

118.8

128.8

75.0

88.8

99.4

108.1

115.5

125.4

92.6

103.6

112.8

123.5

138.5

157.9

78.4

89.9

98.8

107.8

117.5

129.9

80.2

92.1

104.7

109.0

113.3

126.4

94.1

104.1

111.9

125.6

140.0

157.2

80.1

91.0

97.9

109.6

119.0

129.2

75.4

88.6

99.2

108.1

115.4

125.6

92.7

103.4

112.6

123.4

138.6

158.3

77.7

88.4

97.6

107.7

117.6

130.3

80.1

92,4

104.5

108.8

113.4

127.4

93.8

104.3

111.9

125.5

140.7

157.3

78.8

89,3

96,9

109.2

118.8

129.3

Girls —

6 years . . . . . . . . .

7years . . . . . . . . .

8years . . . . . . . . .

9 years . . . . . . . . .

10 years . . . . . . . .

11 years . . . . . . . .

Female equivalent

Girls —

6years . . . . . . . . .

7years . . . . . . . . .

8 years . . . . . . . . .

9 years . . . . . . . . .

10yeers . . . . . . . .

11 years . . . . . . . .

Male standard

Boys

6 years . . . . . . . . .

11 years . . . . . . . .

Standard error of the mean

0.67

0.66

1.35

0.95

0.70

0.66

1.50 0.73

1.11 0.64

1.13

0.98

1.42

2.06

0.72 1.32

0.65 0.95

0.78

0.65

1.37

0.96

0.75

0.66

1.43

0.98

Girls

6years . . . . . . . . .

11 years . . . . . . . .

0.77

0.73

1.70

2.10

0.73

0.60

1.72 I

0.72

1.95 0.71

0.74 1.52

0.70 1.95

0.80

0.73

1.49

2.02

0.72

0.69

1.62

2.10

——Actual valuas

8oys: 6-11 years. . . .

Girls: 6-11 years. . . .

Mean skeletal age in months

102.1 104.0 101.9 104.0

120.8 120.8 120.7 120.9

102.4 102.2 102.2 102.0

120.9 120.4 120.8 120.3

102.6

122.1

102.7

122.1

101.0

120.8

101.2

120.9

0.34

0.32

101.7

120.4

101.0

120.3

101.8

120.8

103.8

121.0

101.8

120.8

104.0

120.9

102.6

121.6

Expected values

Boys: 6-11 years. . . .

Girls: 6-11 years. . . .

102.4

121.8

102.2

121.0

101.9

120.4

102.2

121.0

101.9

120.3

Standard error of the mean

Boys: 6-11 years. . . .

Girls: 6-11 years . . . . -EIE 0.63 0.32 0.63 0.33 0.70 0.33 0.69 0.35 0.67

0.84 0.30 0.79 0.30 0.78 0.30 0.80 0.33 0.81

58
Table 10. Mean bone-specific skeletal ages for the 31 individual hand-wrist bones of bow and airls. bv qeOgraDhiC reaion and chronological age at last birthday, with selected

standard errors: United Stat&, 1“863>5 - -

Radius Ulna Capitate

Standard of reference, sex, and chronological age

at last birthday North

east

South West

Male standard

Mean skelatd age in months

88.0

90.2

96.6

105.8

112.1

122.2

90.5

96.3

106.7

119.1

133.2

150.5

86.8

87.7

92.8

104.1

113.6

124.7

87.1

91.4

97.6

103.8

111.5

122.7

88.4

97.9

106.6

115.3

132.8

153.6

84.6

87.9

92.8

99.4

113.4

126.8

75.0

87.3

96.7

107.0

114.2

127.4

85.7

98.8

108.4

124.S

134.7

155.6

78.0

90.4

95.2

108.8

115.4

128.3

1.50

0.97

0.76

1.87

100.8

115.6

99.7

114.0

0.74

0.76

74.8

85.9

94.4

106.4

113.9

123.8

87.8

97.2

108.6

117.1

134.6

152.0

79.9

86.3

96.3

102.1

115.3

128.0

1.43

0.63

1.02

1.07

74.8

84.9

94.3

104.4

112.8

123.3

82.8

96.4

107.3

116.2

133.0

156.6

75.9

87.7

94.6

101.2

114.0

128.8

1.21

1.27

1.25

1.9-7

83.4

89.7

97.7

106.0

113.3

126.4

90.3

98.8

107.7

123.1

132.7

153.2

86.6

88.2

93.7

107.6

113.4

126.6

76.9

87.5

97.2

105.7

115.1

128.4

88.4

100.5

110.6

125.2

136.2

154.3

76.4

87.5

96.3

109.1

116.2

127.3

0.64

1.21

0.30

2.18

lot.4

116.5

100.1

115.4

0.72

0.84

75.0

87.6

95.2

106.8

114.5

123.2

91.0

100.6

110.6

120.9

137.2

153.2

79.0

87.6

96.3

10.59

117.1

126.6

76.5

84.6

98.5

106.2

114.4

123.5

87.5

98.1

109.5

120.6

136.5

153.7

75.5

86.1

95.5

106.5

116.5

126.8

77.1

85.8

94.6

103.6

112.8

124.0

85.0

98.8

109.4

117.0

135.8

157.4

72.5

86.8

95.4

102.5

115.9

129.4

1.48

2.36

1.34

2.40

99.4

116.6

100.2

116.8

75.2

84.3

98.0

107.0

114.1

122.8

85.3

96.3

108.6

118.6

135.2

153.6

77.4

87.6

95.3

103.8

115.6

126.8

1.05

0.71

1.45

0.93

84.9

92.9

97.2

105.7

113.8

122.7

92.7

99.2

107.8

118.6

133.5

150.3

87.1

88.0

93.8

103.6

113.8

124.6

Girls —

Female equivalent

Male standard

80YS Standard error of the mean

—

6years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

llvears . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

0.96 I 2.18 I 2.12 I 1.41 0.99 1.02

1.06 0.71

1.06 1.25

0.81 1.11

100.7 99.3

118.8 118.0

100.9 99.3

118.2 118.6

1.00 0.95 0.48 1.72

0.70 0.65 0.62’ 1.24

2.22 1.06 0.84 2.05

Girls —

6yoars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Actual values

8oys:6.11years, . . . . . . . . . . . . . . . . . . . . . . . . .

Glrls:6.11year$ . . . . . . . . . . . . . . . . . . . . . . . . .

Mean skeletal age in months

106.4 106.6 105.7 105.5

117.1 118.4 118.8 116.6

105.8 106.3 106.1 106.0

115.9 118.1 119.5 117.5

100.3 99.1

116.4 117.1

100.5 98.9

116.7 117.2

‘%1 ::

98.8

114.1

99.8

115.2

0.71

1.06 I

Expected values

6oys:6-ll years . . . . . . . . . . . . . . . . . . . . . . . . . .

Girls:6.11 years . . . . . . . . . . . . . . . . . . . . . . . . . .

Boys:6.11 years. , ..,..,... . . . . . . . . . . . . . . .

Girls:6-llyears . . . . . . . . . . . . . . . . . . . . . . . . . .

59
Table 10. Mean bone-specific skeletal ages for the 3f individual hand-wrist bones of boys and girls, by geographic region and chronological age at last birthday, with selected

Standard of reference,

sex, and chronological

age at last birthday

Male standard

—Boys

6years . . . . . . . . .

7years . . . . . . . . .

8years . . . . . . . . .

9years . . . . . . . . .

10years . . . . . . . .

11 years . . . . . . . .

Girls —

6years . . . . . . . . .

Jyears . . . . . . . . .

8years . . . . . . . . .

9years . . . . . . . . .

10years . . . . . . . .

Ilyears . . . . . . . .

Female equivalent

Girls —

6years . . . . . . . . .

7years . . . . . . . . .

8years . . . . . . . . .

9years . . . . . . . . .

10years . . . . . . . .

11 years . . . . . . . .

Male standard

BOYS —

6years . . . . . . . . .

llyears . . . . . . . .

Girls —

6years . . . . . . . . .

11 years . . . . . . . .

Actual values

Boys:6-ll years. . .

Girls:6.11 years. . . .

Expected values

Boys: 6-11 years. . . .

Girls: 6-11 years . . . .

Boys: 6-11 years. . . .

Girls: 6-11 years . .

standard errors: United States, 1963.65-Con.

Hamate Triquetrd Lunate Scaphold

North- MidSouth West

North- MidSouth West

North- Mid- NorthSouth Mideast west east west

West

east west South west

east west

Mean skeletal age in months

77.1

B7.O

97.0

105.9

115.2

129.7

88.3

100.4

110.3

126.4

137.6

155.6

76.3

B6.6

96.3

109.7

116.8

12B.3

0.56

1.22

0.47

1.94

74.2

87.0

94.2

104.7

115.1

124.9

B9.6

100.5

111.4

123.0

139.6

154.2

77.6

87.8

97.2

107.5

118.4

127.2

1.04

1.08

1.33

0.71

101.6 100.5

117.1 119.8

100.0 100.9

116.2 119.0

%1 E

76.4

84.6

97.B

105.9

115.1

125.4

87.0

98.2

109.2

122.2

138.4

154.9

75.0

85.1

95.2

107.1

117.4

127.9

1.02

0.89

1.08

0.67

77.0

84.6

94.0

103.4

112.7

124.2

85.2

98.5

109.5

1 lB.4

137.4

156.8

73.2

B5.2

95.5

103.4

116.7

12B.9

1.54

1.91

0.97

1.93

99.5 99.0

118.8 116.2

99.3 100.1

119.4 117.5

%1 E

75.5

86.9

97.3

106.7

114.B

?27.0

90.0

103.1

111.1

124.3

134.2

150.6

77.0

89.1

96.1

107.3

115.1

124.8

1.44

1.11

0.46

2,23

71.9

87.2

96.3

106.3

114.5

123.4

92.9

102.5

112.2

121.1

135.6

149.6

79.9

88.5

97.2

105.6

115.6

124.3

1.96

0.81

1.20

1.25

101.1 100.6

115.8 118.7

100.0 101.0

114.9 117.8

RI E

73.4

84.8

99.5

108.0

114.9

123.4

88.6

100.7

110.3

120.8

133.2

149.7

75.6

86.7

95.3

105.4

114.2

124.4

74.7

85.6

95.7

105.5

112.9

123.0

87.0

101.6

110.7

118.0

132.9

152.B

74.0

87.6

95.7

103.0

113.9

125.9

71.6

82.5

94.6

105.1

114.0

128.2

86.0

99.6

108.0

124.2

133.8

151.6

71.0

89.7

86.2

108.2

114.8

125.6

69,6

85.4

93.6

106.8

115.0

124.1

90.2

98.3

111.0

120.8

135.0

14B.3

75.2

87.4

86.6

105.8

115.5

123.3

Standard error of the mean

1.29 2.25 1.18 1.34

0.80 1.36 1.27 1.05

1.04 0.98 0.88 1.52

1.09 1.86 2.21 1.02

Mean skeletal age m mcmths

68.8

81.8

97.1

105.9

114.B

124.4

82.f

94.7

107.9

119.3

133,1

151.0

67.1

B2.o

88.2

104.3

114.1

125.0

2.68

0.94

1.36

0.70

99.7 99.4 99.5 100.3 98.1

117.2 115.5 114.6 117.2 115.3

99.4 100.1 98.9 100.0 98.2

118.1 116.5 113.6 116.1 116.7

Standard error of the mean

MI%lwl %1%

71.5

80.B

94.0

103.9

114.1

124.2

81.9

97.0

109.4

116.6

132.7

153.1

66.9

85.0

88.5

101.6

113.8

126.6

1.78

2.14

1.75

1.92

98.3

113.6

99.0

114.7

1.39

1.19

B3.I

91.3

9B.3

105.7

114.7

127.3

95.4

103.7

112.2

124.8

133.8

151.0

78.4

87.0

97.2

108.8

113.9

125.0

1.43

1.04

1.18

2.22

B2.o

93.6

98.5

107.8

114.0

123.7

97.1

103.5

112.1

120.0

134.2

148.6

80.2

86.B

97.1

104.0

114.2

123.6

1.54

0.72

0.84

1.29

105.2 105.7

118.4 ?19.5

104.8 105.5

117.2 119.3

%1 :;

82.9

B9,3

101.3

10B.1

114.7

122.6

92.6

102.7

110,4

120.7

132.7

150.2

75.6

85.8

95.7

105.0

113.6

124.6

0.99

0.99

1.32

0.85

104.3

119.0

104.2

I 19.7

0.50

0.66

86.0

89.4

98.8

105.8

113.2

123.8

92.6

103.2

111.7

118.1

132,7

152.0

75.6

86.3

98.7

103.0

113.G

125.5

1.32

1.51

0.96

2.00

104.3

117.5

104.6

118.2

1.17

0.69

60
Table 10. Mean bone-specific skeletal ages for the 31 individual hand-wrist bones of boys and girls, by geographic region and chronological age at last birthday, with selected

standard errors: United States, 1963.65-Con.

Standard of reference,

sro$ and chronological

oge at last birthday

Male standard

Boy’s —

6years . . . . . . . . .

7years . . . . . . . . .

Eyears .,....,..

9years . . . . . . . . .

10yems . . . . . . . .

11 years . . . . . . . .

Glds —

6years . . . . . . . . .

7vcars . . . . . . . . .

8yaars . . . . . . . . .

9years . . . . . . . . .

10yOars . . . . . . . .

llymrs . . . . . . .

Female equivalent

Girls —

6ymr s . . . . . . . .

7ynms . . . . . . . . .

8ycars . . . . . . . . .

9ycars . . . . . . . . .

10ymr s........

Ilvems .,.....,

Male standard

60vs —

6vcars . . . . . . . . .

Ilylmrs.! . . . . . .

Girls —

13yl!m . . . . . . . . .

Ilytxm. .. . . . . .

Actual values

BOYS: 6-11 years. . . .

Girls: 6-11 years . . , .

Expected values

BOW: 6-11 years. .

Glds: 6.11 years. . . .

Bow: 6.11 vears. . . .

Girls: 6-11 years . .

Trapezium Trapezoid Metacarpal I Metacarpal 1I

North- MidSouth WestNorth- MidSouth

North- MidWest ~a~t ~e~x Southwest North- Midwest west

South West

east west east west

Mean skeletal aga in months

77.7

84.1

92.9

101.8

110.6

125.0

90.4

101.1

109.6

122.9

133.0

151.4

83.2

88.1

95.6

106.9

114.0

125.2

1.11

0.75

1.43

1.90

100.9

116.0

99.8

114.8

0.49

0.68

76.8

86.0

91.6

102.6

110.4

120.3

92.3

100.4

110.1

118.6

134.0

151.1

B4. 1

87.4

96.o

103.6

114.5

125.0

1.59

1.06

0.92

1.14

101.0

117.8

100.7

117.1

0.68

0.67

75.-1

82.2

94.1

102.6

110.1

121.4

86.6

96.8

107.9

118.7

133.1

151.3

79.B

85.6

93.9

103.7

114.0

125.2

1.02

0.55

1.14

0.69

99.5

116.5

99.4

117.8

77.2

80.9

91.6

100.0

108.7

120.0

87.7

89.4

108.B

116.0

132.7

153.9

81.7

B6.7

94.8

101.0

113.8

126.9

1.28

2.60

1.34

2.21

98.6

115.5

100.0

116.1

0.68 1.08

0.94 1.03

81.2

8B.8

97.1

106.2

114.1

126.3

90.9

103.1

111.0

123.3

133.1

150.4

77.9

90.6

96.0

107.6

114.1

124.7

0.81

0.80

0.83

2.29

103.9

116.3

102.9

115.5

0.49

0.73

81.6

90.6

95.9

107.1

113.3

122.1

93.5

103.3

111.7

120.4

135.1

150.4

81.5

90.3

96.6

105.4

115.6

124.7

1.64

0.90

0.75

1.50

104.0

119.1

103.7

117.9

0.53

0.7B

79.0

B6.2

98.1

106.6

112.9

121.7

89.1

100.4

108.4

119.7

132.3

150.6

76.1

88.4

94.4

104.7

113.6

124.B

80.4

86.0

97.0

104.7

112.2

122.7

89.3

101.0

110.0

116.6

132.5

152.2

76.3

89.0

95.6

101.6

113.8

126.2

72.9

84.9

95.3

104.0

112.4

126.0

91.1

102.4

111.4

126.8

134.7

156.2

76.1

87.4

97.4

109.9

115.4

128.6

71.0

85.2

94.6

105.0

113.1

121.B

93.6

102.2

112.4

122.2

138.8

154.3

78.6

S7.2

98.4

107.1

117.8

127.6

Standarderrorof the mean

0.66 1.32 0.90 1.41

0.48 2.01 0.93 0.86

0.77 1.19 0.B8 0.95

0.83 1.87 2.43 1.39

Mean skeletal age in months

72.0

82.4

95.0

104.7

112.4

122.6

89.7

101.2

110.1

121.2

137.1

154.8

74.7

86.2

96.6

106.2

116.6

127.9

71.5

B2.4

92.6

103.1

109.5

122.3

8S.2

100.9

109.7

118.9

136.8

156.5

73.2

65.9

96.4

103.9

116.4

128.8

0.72 1.BO

0.53 2.19

1.53 0.89

0.58 2.19

102.2 102.1 98.9 99.0 97.0 96.6

117.4 116.0 llB.1 120.8 119.7 117.3

102.6 103.0 97.8 98.7 -97.0 97.9

118.5 117.0 117.2 119.9 120.4 118.5

Standard error of the mean

::1 El Wl :31El :::

75.8

88.4

97.1

106.4

113.0

125.6

90.9

103.2

112.0

127.3

134.5

?55.8

75.9

88.3

97.0

110.3

115.2

12B.4

1.14

0.93

0.50

2.32

100.7

118.5

99.3

116.7

0.69

0.77

74.9

88.2

95.3

106.6

113.0

121.1

92.6

102.2

111.7

121.2

137.4

152.5

77.6

S7.2

96.7

106.2

116.7

126.5

~.88

0.75

0.95

1.22

100.3

119.8

100.1

119.3

0.40

1.06

75.4

84.4

96.8

105.6

113.6

122.2

88.4

100.6

110.0

120.2

136.3

163.3

73.4

85.9

95.0

105.2

116.2

127.2

0.88

0.7s

1.35

0.78

9S.6

118.9

98.5

119.7

0.58

0.92

74.2

84.6

94.2

102.6

111.0

122.6

S7.O

100.4

109.2

117.8

135.3

155.9

72.0

S5.7

94.6

102.8

115.6

128.4

1.49

1.59

1.16

2.06

97.9

116.4

89.4

117.8

1.21

1.05

61
Table 10. Mean bone-specific skeletal aws for the 31 individual hand-wrist bones of boys and girls, by geographic region and chronological afie at last birthday, with selected

Standard of reference,

sex, and chronological

age at last birthday

Male standard

—BOVS

6years . . . . . . . . .

7years . . . . . . . . .

8years . . . . . . . . .

9years . . . . . . . . .

10years . . . . . . . .

11 years . . . . . . . .

Girls —

6years . . . . . . . . .

7year5 . . . . . . . . .

Sears . . . . . . . . .

9years . . . . . . . . .

10years . . . . . . . .

11 years . . . . . . . .

Female equivalent

—Girls

6years . . . . . . . . .

7years .<.......

8years . . . . . . . . .

9years . . . . . . . . .

10years . . . . . . . .

11 years . . . . . . . .

Male standard

80vs —

6years . . . . . . . . .

Ilvears . . . . . . . .

Girls —

8years .,......,

11 years . . . . ...<

Actual values

Soys: 6-11 years.

Girls: 6-11 years . . .

Expected values

Boys: 6.11 years. . . ,

Girls: 6-11 years . . .

BOVS:6-11 years. , . ,

Girls: 6-11 years . . .

standard errors: United States, 1983.65-Con.

Metacarpal III Metacarpal IV Metacarpal V Pisiform

North- Mid- South ~e$t North- Mid- South westNorth- MidSouth West

North- Mideast west east west east west

South West

east west

Mean skeletal age in months

75.2

SB.2

96.9

106.0

112.6

126.0

90.7

103.2

111.8

127.1

136.2

166.6

76.0

89.2

97.s

110.1

116.2

128.B

1.21

o.B1

0.48

2.17

100.5

11S.6

99.2

116.9

0.6B

0.7s

74.8

87.9

95.1

106.9

112.7

121.4

93.0

102.3

111.9

121.6

13B.5

153.7

79.0

88,3

97.9

106.5

117.5

127.4

1.97

0.5s

0,86

1.21

75.7

B4.4

96.8

105.4

113.3

122.4

88.1

100.6

110.0

120.4

136.7

153.8

74.0

BB.5

96.0

105.4

116.4

127.4

0.80

0.73

1.40

0.76

100.3 98.6

120.4 119.0

100.0 98.4

119.6 120.0

0.39 0.60

1.05 0.95

73.B

84.6

94.2

102.1

111.0

123.0

87.2

100.2

109.1

118.0

136.1

15B.9

72.3

86.2

96.1

104.0

116.0

128.9

1.25

1.76

1.20

2.24

74.9

S7.7

96.7

105.8

112.7

126.6

90.4

103.2

111.6

127.0

134.8

156,5

75.4

8B.3

96.6

110.0

115.4

128.8

1.09

0.85

0.44

2.07

97.s 100.2

116.7 11s.4

99.3 98.8

118.1 116.7

1.20 0.71

1.02 0.77

74.2

87.8

94.8

106.6

112.6

121.0

92.2

101.4

111.4

121.5

136.3

153.8

77.2

86.4

96.4

106.5

117.3

127.4

1.91

0.65

0.87

1.23

99.9

120.0

99.6

119.4

0.40

1.04

74.3

S4.2

96.8

105.2

112.7

122.2

B7.9

1OQ.4

109.8

120.2

136.7

154.1

72.9

85.7

94.9

105.2

116.4

127.6

72.9

84.3

93.7

101.6

110.5

122.6

86.7

99.6

1C+3.4

118.0

136.0

156.8

71.7

B5.3

94.2

103.0

116.0

128.9

74.5

87.7

96.6

105.4

112.5

125.4

90.4

102.8

111.2

127.5

136.1

157.4

7’5.4

87.8

96.2

110.2

115.6

129;4

‘ 74.1

87.8

95.2

106.8

112.9

121.6

92.5

101.2

111.7

122.4

140.0

155.3

77.6

B6.2

96.7

106.7

118.5

128.2

Standarderrorof the mean

0.67 1.42 1.07 1.s1

0.70 1.56 1.23 0.s7

1.28 1.19 0.49 1.04

0.76 2.46 2.02 1.09

Mean skeletal age in months

73.6

83.3

96.4

104.9

112.B

122,8

87.2

99.7

109.6

120.9

138.0

155.1

72.2

84.7

94.8

105.9

117.0

128.0

0.70

0.81

1.24

0.82

98.1 97.4 100.0 100.2 97.s

118.9 116.4 118.6 120.8 119.2

9B.O 98.9 98.8 99.6 98.0

119.s 117.9 117.1 119.6 120.2

Standarderrorof themean

0.62 1.18 0.64 0.41 0.55

0.92 1.04 O.BO 1.12 0.99

72.4

84.2

93.8

101.7

110.6

122.6

86.4

99.5

108.7

llB.O

137.4

158.4

71.4

84.5

94.4

103.0

116.4

130,4

1.34

1.83

1.24

2.40

97.3

116.8

98.8

1 lB.3

1.25

1.13

113.0

116.o

118.1

118.9

127.6

119.7

116.5

119.4

128.3

138.0

162.5

104.8

102.8

104.7

111.2

117.0

126.2

0.92

5.25

2.10

122.6

132.9

122.2

132.8

0.5s

1.27

115.0

110.4

116.0

117.9

120.4

127.2

117.2

117.4

121.5

125.5

140.7

152.7

103.2

103.4

106.5

109.5

118.8

126.4

81.31

1.02

1.93

1.41

134.0

114.4

114.4

116.9

119.3

125.1

112.0

114.9

119.0

126.0

137.7

153.6

100.0

101.9

104.5

110.0

116.8

126.B

94.75

0.57

25.08

0.68

...

113.1

114.6

116.3

117.0

127.1

114.6

119.3

120.2

124.5

137.0

156.B

101.6

104.6

105.2

108.5

116.5

128,9

2.41

36.35

2.19

123.0 121.7 122.5

135.7 136.5 135.3

122.3 122.5 123.1

135.4 137.1 136.3

0.55 I

0.56

I

1.8B

1,25 1.01 1.3a

62
Table 10. Mean bone-specific skeletal ages for the 31 individual hand-wrist bones of boys and girls, by geographic region and chronological age at last birthday, with selected

Standard of mfcrence,

sex, and chronological

ago at last birthday

Male standard

BOYS —

6yetm.. .,.....

7years . . . . . . . . .

Eyears . . . . . . . . .

9vears . . . . . . . . .

10years, .,.....

11 years . . . . . . . .

Girls —

6 years . . . . . . . . .

lyears . . . . . . . . .

Eyears .,.......

9years . . . . . . . . .

10years . . . . . . . .

11 years . . . . . . . .

Female equivalent

GM

6years . . . . . . . . .

7years . . . . . . . . .

!3y0ars . . . . . . . . .

9yctIrs . . . . . . . . .

10years . . . . . . . .

llycws . . . . . . . .

Male standard

Boys —

6years . . . . . . . . .

11 years . . . . . . . .

Girls —

6ycars . . . . . . . . .

llycws . . . . . . . .

Actual values

Soys:6-ll years. . . .

Girls: 6.11 years. . . .

Expected values

Eloys: 6-11 years. . . .

Gwls:6-llvears. . . .

B0ys:6.11 years. . . .

Girls: 6.11 years. . . .

standard errors: United States, 1963-65-Con.

Adductor sesamoid Flexor sesamoid Proximal phalanx I Proximal phalanx 11

North- Mid- North- Mid- NorthSouth West

Mid- ~e~t North- MidSouth

east

west

west east

South

west

South

east

West

west east west

Mean skeletal age in months

-.

...

...

15B.2

150.0

156.9

152.0

150.0

159.1

158.8

158.9

162.7

125.5

124.0

130.6

130.4

130.4

132.7

-.

0.58

107.4s

0.55

166.6

160.8

156.5

160.4

0,79

0.52

-.

-.

-.

152.0

159.6

155.5

154.9

154.4

157.9

162.7

-.

-.

127.9

127.4

129.9

132.7

-.

1.79

-.

0.45

156.0

160.0

156.S

160.6

1.16

0.43

—

154.0

157.1

—

—

148.4

157.8

156.9

163.7

—

124.0

129.8

130.4

133.4

2.64

—

0.83

156.8

161.3

156.4

160.7

2.24

0.57

-.

—

164.0

156.6

—

160.0

153.7

155.4

158.5

162.5

-.

131.0

126.7

128.2

130.2

132.5

—

1.36

-.

0.72

156.8

160.4

156.6

160.7

1.34

0.46

-.

.—

—

163.0

15s.0

162.5

—

-.

171.0

162.3

163.4

166.6

—

—

139.0

132.3

133.2

134.6

—

2.18

1.40

162.0

16S.3

160.5

164.4

1.90

0.84

—

—

162.0

156.0

160.3

162.6

165.6

...

130.0

131.2

132.6

134.3

.-

.

0.82

162.0

164.0

161.0

164.2

62.B2

0.60

-.

—

168.0

—

159.1

—

—

161.8

161.9

166.5

—

—

131.9

131.9

134.6

160.0

—

160.0

158.0

160.0

161.6

164.9

...

131.0

130.0

131.0

131.6

133.9

78.5

88.5

98.9

106.3

114.2

127.6

91.8

103.4

113.8

132.4

140.6

161.2

76.B

88.4

99.8

113.7

118.8

131.2

76.8

68.8

97.1

107.6

113.8

123.7

92.5

101.0

115.4

126.1

143.6

159.7

77.5

66.0

100.7

109.6

120.6

130.4

Standard error of the mean

— — 1.31 1.05

. ● 0.80 0.84

-. 0.71 0.79

1.06 0.83 2.31 1.40

Mean skeletal age in months

15s.9

164.6

160.7

164.3

160.0

163.6

161.0

164.7

102.0

121.3

100.2

119.4

101.7

123.2

101.0

122.3

Standard error of the mean

79.44

0.90 RRlw w

75.3

86.0

86.4

104.2

113.B

123.5

69.0

99.4

110.6

125.4

141.5

159.9

74.5

64.4

96.2

109.2

118.2

130.4

0.86

1.07

0.80

1.12

9B.7

121.8

99.5

122.8

0.71

0.s9

75.6

66.3

95.0

101.5

110.9

124.2

86.8

99.1

110.7

121.7

141.2

161.7

71.8

84.1

96.4

106.4

119.1

131.7

1.17

2.66

1.05

2.39

60.6

91.5

10?.0

108.0

115.4

127.9

94.4

106.1

115.1

131.5

140.3

161.5

79.4

91.1

100.1

112.8

118.6

131.2

1.04

0.97

0.76

1.81

98.7 103.7

119.0 122.5

100.3 101.9

120.8 120.5

1.54 0.71

1.39 0.87

79.3

Q2.4

99.s

109.3

115.0

124.1

86.1

103.9

115.9

125.5

143.4

159.8

81.1

86.9

100.9

108.5

120.7

130.4

1.51

1.04

0.80

1.02

103.7

124.2

102.7

123.2

0.37

0.93

77.1

87.4

97.9

105.1

114.0

123.8

90.7

101.6

112.1

124.5

141.1

159.5

75.7

86.6

97.1

107.8

118.1

130.2

0.83

0.97

0.93

0.95

99.8

122.3

101.2

123.7

0.57

0.95

78.5

88.1

96.9

104.4

112.4

124.9

88.1

101.8

111.6

121.9

141.4

161.3

74.1

86.8

96.8

105.9

119.4

131.2

1.27

2.40

1.19

2.57

100.6

120.0

102.0

121.8

1.47

1.29

63
Tabie 10. Mean ixmeWecific skeletal ages forthe31 individual hand.wrist bones of bqsandgi rls,byge ographicre .gionandc hronological awatiast tirthtiv, with selectad

Standard of reference,

sex, and chronological

age at last birthday

Male standard

BOYS —

6years . . . . . . . . .

7years . . . . . . . . .

8years . . . . . . . . .

9years . . . . . . . . .

10years . . . . . . . .

Ilyeam< . . . . . . .

Girls —

6years . . . . . . . . .

7years . . . . . . . . .

%years . . . . . . . . .

9years . . . . . . . . .

loyears . . . . . . . .

Ilvears . . . . . . . .

Female equivalent

Girls —

6years . . . . . . . . .

7years . . . . . . . . .

8years . . . . . . . . .

9years, . . . . . . . .

10years . . . . . . . .

llyears . . . . . . . .

Male standard

—80Ys

6years . . . . . . . . .

Ilyears . . . . . . . .

Girls —

6years ...,.....

llyears . . . . . . . .

Actual values

Boys: 6-11 years. . . .

Girls:6-llyears. . . .

Expected values

BOyK 6-11 years. . . .

Giris:6-ll years. . . .

BoYs:S.11 years. . . .

Girls: 6-11 years. . . .

Proximal phalanx III

79.9

90.6

100.6

107.8

116.5

127.8

94.1

105.6

114.8

131.4

140.4

161.6

79.1

90.6

99.B

113.2

118.7

133.3

1.06

1.05

0.B7

1.86

103.4

122.3

101.6

120.3

78.7

91.9

99.6

109.6

115.2

124.1

95.9

103.5

115.9

125.3

144.2

160.1

80.9

B6.5

100.9

109.2

121.1

132.1

1.66

1.02

0.87

1.05

103.6

124.3

102,4

123.1

0.73 0.3s

0.B8 I 1.02

76.4

86.4

97.5

104.B

114.1

123.7

90.0

101.3

111.6

124.5

141.1

159.5

75.0

86.3

96.6

10s.5

119.0

131.B

0.84

1.11

0.86

0.91

99.4

122.1

100.9

123.6

0.61

0.95

77.8

B7.5

96.5

103.7

112.4

125.1

88.2

101.0

111.9

121.9

141.3

161.7

73.2

86.0

96.9

106.4

119.2

133.4

1.33

2.41

1.12

2.60

100,2

119.8

101.7

121.6

standard errors: United States, 1963.65-Con.

Proximal phalanx IV I Proximal phalanx V I Middle phalanx II

Vorth- MidSouth ~e~t North- MidSouth~e~t North.

east west east west east

Mean skeletal age in months

79.0

90.4

100.6

107.7

116.1

12s.7

93.8

105.6

115.1

131.8

140.4

161.1

78.B

90.6

100.1

113.4

118.7

133,0

1.19

0.96

0.95

1.91

103.4

122.2

101.6

120.4

1.43

I

0.76

1.37 0.91

77,B

91.8

99.7

109.4

115.9

125.0

95.4

103.9

116.6

125.9

144.0

160.4

Bo.4

B8.9

101.6

109.4

121.0

132.4

1.71

0.99

0.89

1.22

103.7

124.5

102.4

123.2

0.44

0.93

75.7

86,2

97.6

105.1

114.9

124.1

89.9

101.0

111.6

124,7

141.2

160.0

74.9

86.0

96.5

108.7

119.1

132.0

75.8

87.3

96.3

104.0

113.0

125.2

B8.2

101.3

112.0

122.1

141.6

161.9

73.2

86.3

97.0

10S.6

119.3

133,4

79.6

90.8

101.2

107.8

116.2

129.0

94.3

10s.0

115.4

132.3

140.8

161.6

80.2

91.0

101.4

113.6

119.3

131.B

7B.4

92.2

100.3

109.2

115.9

124.9

95.8

103.9

116.B

126.2

143.7

160.4

80.9

88.9

102.4

109.6

120.7

131.2

Standarderrorof the mean

0.79 1.18 1.10 1.&l

0.92 2.36 0.93 0.9B

0.96 1.06 0.B3 0.90

0.92 2.50 1.65 1.18

Mean skeletal age in months

9s.4 100.2 103.7 104.0

122.2 119,9 122.7 124.6

I 00.9 101,7 102.0 102.8

123.7 121.8 120.7 123.4

Standard error of the mean

%1 :21%1 ‘w

76.2

87.1

9B.5

105.9

114.8

124.8

90.2

101.1

112.5

124.7

141.8

160.0

76.2

86.1

98.5

10s.7

119.6

131.0

0.85

1.11

0.99

1.01

77.4

87.9

96.8

104.2

112.8

125.2

B8.8

101.6

112.2

122.5

141.9

162.0

73.8

86.6

9s.2

107.2

119.6

132.0

1.23

2.0s

1.03

2.33

100.1 100.5

122.4 120.3

01.2 102.1

23.9 122.0

0.57

I

1,37

0.82 1.34

82.9

92.5

102.3

109.4

116.9

129.8

95.8

106.2

116.3

131.7

141.2

160.5

80.B

91.6

101.6

113.6

119.1

131.2

0.71

0.90

1.11

2.18

105.3

123.0

103.4

120.8

0.59

1.03

&kk

80.3

93.6

101.1

109.7

115.1

125.7

96.B

103.6

116.7

126.1

143.2

159.1

81.B

B9.6

101.4

109.6

120.2

130.6

0.89

0.74

0.77

1.26

79.3

88.6

99.8

107.1

116.5

125.1

91.9

102.1

112,5

125.0

140.7

150.0

77.4

88.7

97.5

109.0

llB.B

131.0

0.92

0.93

1.12

0.93

104.6 101.6

124.2 122.9

104.2 102.7

123.5 124.2

0.36

I

0.58

0.87 0.81

B1.1

90.3

98.4

106.4

113.8

126.6

90.6

101.9

112.5

122.6

141.4

161.5

76.6

87.9

97.5

107.3

119.2

131.5

1.06

1.99

O.BO

2.43

102.5

120.6

103.6

122.2

1.26

0.93
Table 10. Mean bone-specific skeletal ages for the 31 individual hand-vmist bones of boys and girls, by g+cgraphic region and chronological age at last birthday, with selected

Standard of reference,

sex, and chronological

age at last birthday

Male standard

BOVS —

6years ...,...,.

7years . . . . . . . . .

8years . . . . . . . . .

9years ..,.,.,..

Ioy’ears ...,....

llvenrs ..,.....

Girls —

6years . . . . . . . . .

7years .,.......

Bears. ..,.....

9years ..,......

10years . . . . . . . .

llvears ...,,,..

Female aquiv.alcmt

Girls —

6ymrs . . . . . . . . .

7years .,......,

8vmrs ...,,....

9yt3ar5, . . . . . . . .

10yeara ...,.,..

llyears . . . . . . . .

Male standard

Boys —

6years . . . . . . . . .

11 years . . . . . . . .

GAs

6years . . . . . . . . .

11 years . . . . . . . .

Actual values

Boys: 6.11 years. . . .

Glrla: 6.11 years. . . .

Expected values

Boya:6.llyears, , . .

Glrls:6.11yeara. . . .

Boys: 6.11 years. , . .

Girls: 6.11 years . . . .

standard errors: United States, 1883J35-Con.

Middle phal.mx III IMiddla phalanx IV I

Middle phalanx V IDistal phalanx I

81.1

91.3

101,2

10B.7

118.6

129.1

84.7

105.6

115.2

131.4

140.7

161.3

79.7

91.3

101.1

113.5

118,8

131.4

0.45

0.93

1.15

1.66

78.7

91.9

99.8

109.1

114.s

125.6

95.3

102.6

115.1

125.9

143.5

158.9

80.3

88.6

101.0

109.4

120.5

130.4

0.87

0.76

0.85

1.30

77.9

87.4

98.6

106.5

115.7

125.0

90.2

101.0

111.2

124.5

140.4

159.8

76.2

B7.O

98.2

106.5

118.7

130.9

0.90

0.83

1.20

0.94

79.2

88.4

97.3

105.6

113.3

126.4

89.B

100.8

111.9

121.6

140.7

161.4

75.8

86.8

96.9

106.8

118,8

131.5

1.29

2.26

0.67

2.56

104.3 103.B 100.7 101.5

122.5 123.7 122.0 119.9

102.5 103.2 101,7 102.6

120.2 122.9 123.4 121.5

WI ::1 RI :5:

North- MidSouth West

east west

81.2

91.7

101.6

108.4

116.0

128.2

95.1

105.5

114.8

130.4

138.8

160.6

80.1

91.2

100.7

113.1

118.4

131.2

0.71

0.90

1.10

2.01

104.2

122.1

102.5

119.9

0.63

1.05

79.4

93.0

100.5

106.5

114.2

124.6

96.0

102.9

114.5

125.2

142.2

158.3

81.0

88.9

100.2

108,1

119.6

130.2

0.83

O.B1

0.72

1.40

103.8

123.4

103.3

122.6

0.38

0.83

North.

east

MidSouth west

Nmth- Midwest east west

Mean skeletal age in months

78.2

88.1

99.2

106.9

115.2

123.8

79.8

89.5

97.9

105.8

113.0

125.2

90.6 90.4

101.2 101.3

111.2 111.3

123.6 121.1

139.1 139.9

159.0 161.1

76.6 76.4

87.2 87.3

96.2 88.3

107.8 106.1

118.0 1 lB.4

130.5 131.4

80.S

91.2

101.2

108.2

116.3

12S.7

95.2

105.6

115.1

131.1

140.3

160.3

78.3

91.3

100.1

112.6

118.3

130.6

78.6

92.2

101.1

109.2

114.4

125.2

96.4

103.5

115.0

125.6

142.4

159.4

80.1

89.5

100.0

108.6

119.7

130.5

Standard error of the mean

0.91 1.26 0.94 0.64

0.83 2.28 0.74 0.62

1.21 0.90 1.08 0.80

1.00 2.63 1.99 1.19

Mean skeletal age in months

100.B 101.7 104.0 103.9

121.6 119.7 122.2 123.8

101.s f 02.7 102.5 103.4

123.1 121.2 120.1 122.9

Standard error c.f the mean

%1 %[ MI ::

76.9

87.6

88.6

107.3

115.7

124.7

91.1

100.8

111.3

123.6

140.1

159.7

72.2

S5.6

96.3

107.3

118.1

130.6

1.02

1.11

1.32

1.02

100.7

122.0

101.8

123.5

0.s6

0.63

79.6

89.6

98.4

105.7

113.2

125.9

91.0

101.3

111.7

121.6

140.2

161.8

72.0

85.4

96.7

108.3

118.2

131.6

1.09

2.18

0.62

2.76

101.B

120.1

102.7

f 21.6

1.40

t .06

76.2

89.0

101.0

108.9

116.5

128.9

93.9

104.9

114.0

130.8

140.0

159.3

77.9

69.9

99.0

112.8

118.0

130.6

0.97

0.61

1.08

1.65

103.0

121.1

101.1

I 16.B

0.84

0.93

74.2

89.C

99.9

?08.9

115.4

125.0

94.1

102.5

115.1

124.7

141.1

157.7

78.1

87.5

100.1

107.6

119.0

129.7

1.11

0.62

0.69

1.17

102.6

122.4

101.8

121.6

0.41

1.04

South I West

73.3

85.1

98.8

107.2

114.8

124.6

88.7

99.8

110.6

123.8

139.2

158.4

72.7

84.8

95.6

107.4

117.6

130.2

1.15

0.91

1.30

0.85

99.4

120.8

100.2

122.3

0.76

0.68

73.4

85.5

96.9

105.5

112.6

125.2

87.6

101.3

111.7

120.7

139.3

159.6

71.B

86.3

96.7

105.7

117.6

130.9

1.52

2.28

1.11

1.96

99.7

116.5

101.2

120.2

1.54

1.30

65
Table 10. Mean bone-specific skeletal ages for the 31 individual hand-wrist bones of boys and girls, by gf+zgraphic region and chronological age at last birthday, with selected

standard errors: United States, 1883.85-Con.

I I I

Distal phalanx I I I Distal phalanx I I I I Distal phalanx IV I Distal phalanx V

Standard of reference,

sex, and chronological

age at last birthday South West

North- MidSouthwest North- MidSouth

east west

West

east west

North. I

Mideast westMidwest

76.5

91.0

100.1

10s.9

116.1

125.1

95.8

104.2

114.2

123.2

139.6

155.7

81.8

91.1

100.2

107.6

118.6

128.4

0.81

1.03

0.90

1.36

jouth

76.8

88.6

101.3

108.1

115.0

124.0

90.9

I 02.2

111.6

123.3

137.6

157.3

75.9

87.2

96.6

107.6

116.8

129.3

1.05

0.94

1.24

0.83

Male standard

—80YS

6years . . . . . . . . .

7years . . . . . . . . .

8years . . . . . . . . .

9years . . . . . . . . .

10years . . . . . . . .

llyears . . . . . . . .

Meanskeletalage inmonths

77.4

91.0

101.8

109.6

116.1

127.6

95.6

106.5

113.7

129.6

138.2

158,1

80.6

91.5

98.7

111.6

117.2

130.0

0.89

0.60

1.25

1.72

103.6

121.2

102.3

119.0

0.75

1.06

77.0

91.6

100.4

109.0

115.9

124.8

96.3

104.4

114.4

123.2

139.3

155.2

81.3

89.4

99.4

107.6

118.3

128.1

0.80

0.97

0.82

1.48

76.8

91.0

101.6

109.3

116.2

127.8

95.1

106.4

113.7

129.7

139.2

158.1

81.1

92.4

99.7

112.4

115.2

130.0

0.91

0.65

1.25

1.79

75.9

87.5

98.2

106.5

113.6

125.1

91.0

101.8

111.2

119.5

137.2

158.9

76.0

87.8

97.2

104.5

116.6

130.4

76.6

90.9

101.4

109.3

116.0

128.1

95.2

106.3

113.7

129.8

138.6

158.4

81.2

92.3

99.7

112.4

117.6

130.2

76.1 I

91.1

100.2

109.0

115.9

125.2

95.6

104.3

114.4

123.1

139.8

156.4

81.6

91.2

100.4

107.6

118.8

128.7

75.4

87.8

101.2

75.3

87.4

98.3

106.7

113.6

125.3

90.4

101.8

111.1

119.7

137.6

159.3

75.4

87.8

97.1

104.7

116.8

130.6

1.62

2.05

0.75

2.01

100.9

118.6

102.2

t20.3

76.6

91.0

100.0

109.0

115.4

125.5

95.6

103.8

114.4

123.1

140.1

157.0

60.6

88.8

99.4

107.6

118.6

129.0

0.93

0.87

0.96

1.28

103.4

122.4

102.9

121.8

75.6

87.8

100.8

108.0

115.4

124.7

90.4

101.6

110.9

123.2

130.9

156.2

75.4

86.6

95.9

107.6

117.9

130.2

1.21

1.00

1.24

76.4

87.2

97.9

106.6

113.6

125.3

91.0

101.8

111.0

119.6

137.9

159.4

76.0

86.6

96,0

104.6

116.9

131.2

1.74

2.11

0,93

2.01

101.0

118.7

102.2

120.3

1.76

1.13

76.8

87.7

98.8

106.5

113.6

125.0

91.4

102.3

111.4

119.7

137.2

158.8

76.4

87.3

96.4

104.7

116,6

130.3

1.60

1.99

0.85

2.12

101.2

118.7

102.4

120.2

76.0

88.3

101.3

108.2

115.2

124.1

90.5

101.9

111.3

123.4

136.4

157.4

75.5

87.9

97.3

107.7

117.4

129.4

76.2

90.6

101.3

109.3

116.0

128.4

94.8

106.5

113.4

129.8

139.3

158.7

79.8

91.5

98.4

112.4

118.2

130.7

0.69

0.80

1.25

1.77

103.3

121.2

102.1

119.0

0.68

1.11

108.0

116.2

124.1

—Girls

6years . . . . . . . . .

7years . . . . . . . . .

8years . . . . . . . . .

8years . . . . . . . . .

10years . . . . . . . .

11 years . . . . . . . .

90.6

101.9

111.2

123.5

138.9

157.8

75.6

87.9

97.2

107.8

117.9

129.8

1.06

0.87

1.34

0.95

1043.8

121.3

101.2

122.2

Female equivalent

Girls —

6years . . . . . . . . .

7years . . . . . . . . .

8years . . . . . . . . .

9years . . . . . . . . .

10years . . . . . . . .

11 years . . . . . . . .

Male standard

—80YS

6years . . . . . . . . .

11 years . . . . . . . .

Standard error of the mean

1.01 1.48 1.03 0.89

0.92 2.02 0.67 1.05

1.32 0.86 1.33 1.00

0.82 2.05 1.78 1.37

Mean skeletal age in months

101.0 101.0 103.4 103.4

121.1 118.5 121.1 122.4

101.3 102.3 102.0 102.9

122.1 120.2 119.0 121.8

Standard error of the mean

Girls —

6years . . . . . . . . .

11 years . . . . . . . . 0.80

Actual values

80YS: 6-11 years. . . .

Girls:6-ll years. . . .

103.6

122.2

101.2

121.1

103.4 103.4

121.1 122.2

100.9

121.2

101.2

122.3

Expected values

80YS: 6-11 years. . . ,

Girls:6.llyears. . . .

103.1

121.7

101.5

122.2

102.1 102.9

118.9 121.7

60Ys:6-11 years. . . .

Girls: 6-11 years. . . . El-E 0.70 1.62 0.79 0.45 0.72 1.66

o.6a 1.09 1.05 0.85 0.90 1.10 &l-&

66
Table 11. Mean bone-specifio skeletal ages for salected hand-wrist bones of boys and girls, by annual family income and chronological age at last birthday, with

Standard of reference, sex, and

chronological ege at

last birthday

Male standard

Boys —

6years . . . . . . .

7years .,.....

Bears, . . . . . .

9years ...,,,.

10years . . . . . .

11 years . . . . . .

Girls —

6 years..,.,..

?years ..,.,,.

6years, ..,...

9years, ,, ...,

10years .,, ,..

11 years . . . . . .

Female equivalent

Girls —

6years ...,...

?years ..,....

Bears . . . . . . .

9yeers, . . . . . .

10years . . . . . .

11 years ., ..,.

Male standard

Boys —

6 years ...,..,

11 years . . . . . .

G&s

6years, . . . . . .

11 years . . . . . .

Actual values

Boys: 6-n years. .

Girls: 6.11 years, ,

Expected values

Boys: 6.11 yeers. .

Girls: 6.11 years, ,

Boys: 6-11 years. .

Girls: 6-11 years. .

selected standard errors: United States, 1853-65

Triquetral Metacarpal Ill

Less than

$3,000

72.3

65,2

96.4

104.2

113,5

124.2

91.2

102.6

1OB.6

120.1

134.1

150.4

76.2

68.6

94.3

106.0

115.0

124.7

$3,00G $5,000- $7,000- $10,OOB $15,000 Less than $3,00G $5,000-

$4,999

$7,000 $10,000- $15,000

55,999 $9,999 $14,999 or more $3,000 $4,999 $8,999 $9,999 $14,999 or more

74.6

B5.9

88.8

106.5

115.3

125.7

69.6

100.9

112.1

119.3

133.6

148,9

76.6

66.9

97.1

104.3

114.6

123,9

2.54 1.51

1.60 1.21

1.00 1.47

1.67 1.52

99.2

116.5

99.8

116,6

0,76

0.68

100.4

115.9

99.5

116.4

0.80

0.71

75.6

87.3

96.9

107.2

115.1

123.7

87.1

101.5

111.3

119.9

133.8

151.2

74.1

87.5

96.3

104.9

114.8

125.1

1.36

1.63

1.53

0.99

100.2

116.8

99.5

117.3

0.57

0.94

71.4

34.2

97.2

105.2

115.1

123.5

90.3

102.8

112.3

123.9

133.9

150.0

77.3

88.8

97.3

106.9

114.9

124.5

1.91

1.11

1.60

1.12

100.4

116.8

101.2

116.0

0.94

0.58

N

72.7

90.2

64.0

108.9

111.9

124.6

90.5

101.0

109.8

122.1

132.5

149.0

77.5

87.0

94.9

105.0

113.8

124.0

n skeletal ageinmon

76.2

85.2

95.5

106.6

115.1

125.6

86.8

107.4

111.5

124.2

136.6

153.5

75.6

93.4

95.5

107.2

115.3

126.5

73.6

84.0

94.8

102.0

111.7

125.0

90.2

102.2

107.5

119.4

138.2

154.1

75.3

86.2

93.5

104.7

117.2

76.0

68.6

96.5

104.7

112.9

123.9

90.1

100.6

111.5

120.5

135.9

155.2

75.2

85.6

97.5

105.5

115.9

128.1

Standerd error of the mean

3.43 2.20 1.90 1.16

1.71 2.32 1.76 1.41

1.79 3.73 1.48 1.97

2.(24 3.53 1.60 1.51

Mean skeletal age in months

101.0

117.1

100.8 97.7

120.7 117.9

100.9

I

100.3 I

98.7

117.7 118.6 118.4

76.1

67.4

95.0

106.6

113.1

123.1

B6.4

101.0

111.4

121.3

135.8

155.4

74,2

87.0

97.4

105.3

115.8

128.2

73.9

86.2

95.9

104.7

113.4

121.8

90.8

102.0

112.5

123.7

135.5

155.1

75.2

B8.O

98.5

108.4

116.2

128.6

1.04 1.73

1.61 1.06

1.73 0.91

1.07 1.26

99.2 99.4

117.9 118.8

96.6 98.7

118.2 119.2

%andard error of the mean

1.30 I

2.17 I

1.13 0.78 I0.45

1.23 1.97 1.07 0.89 1.11

100.1

118.8

10Q.2

117.8

0.B5

0.70

73.6

87.4

64.6

108.0

110.1

122.4

87.8

101.1

109.0

125.3

135.1

153.6

73.2

87.1

95.0

109.3

115.1

127.3

3.33

1.87

1.82

2.06

99.8

118.7

100.0

119.3

1.24

1.40

72.6

86.3

96.7

107.5

111.0

123.9

92.2

108.5

113.1

122.3

140.5

157.7

78.2

94.5

99.1

107.3

119.2

129.7

2.69

2.81

4.26

4.10

99.7

123.6

99.6

120.6

2.22

1.90

67
Tabla 11.Mean bOne-sDecific skeletal aaes for selected hand-wrist bones of bovs and girls, bv annual familv income and chronological age at last birthdav, wnh

selected standard errors: United States, 1963-66—Con.

Standard of reference, sex, and

chronological age at

last birthday

Male standard

6vears . . . . . . .

7 years . . . . . . .

8vears . . . . . . .

9vear5 . . . . . . .

10years . . . . . .

11 years . . . . . .

Girls —

6 years . . . . . . .

7years . . . . . . .

8 years . . . . . . .

9vears . . . . . . .

lOyears . . . . . .

11 years . . . . . .

Female equivalent

Girls —

6years ...,...

7years . . . . . . .

8years . . . . . . .

9 years . . . . . . .

lOyears . . . . . .

11 years . . . . . .

Male standard

Boys

.

6vears . . . . . . .

11 years . . . . . .

—Girls

6years . . . . . . .

11 years . . . . . .

Actual values

Boys: 8-11 years. .

Girls: 6-11 years . .

Expected values

Boys: 6-11 years. .

Girls: 6-11 years . .

Boys: 6-11 years. .

Girls: 6-11 years. .

Metacarpal V

Less than $3,000 $6,00@ $7,000- $1o,ooo- $15,003

$3,000 $4,999 $6,999 $9,999 $14,999 or more

71.8

64.1

94.0

101.7

111.8

124.8

89.8

101,7

107.3

119.9

139.4

155.2

74.8

86.7

92.4

1W.9

118.2

128.1

2.04

1.70

1.40

1.74

97.1

118.2

98.3

118.6

1.09

1.19

75.1

85.7

98.4

104.1

112.8

124.6

89.0

99.9

111.4

120.4

137.5

158.7

74.0

84.9

96.4

105.4

116.5

128.8

1.29

1.47

2.08

1.44

98.9

118.1

98.2

118.4

0.80

0.97

74.6

87.3

96.1

106.1

112.7

122.6

87.8

99.8

110.8

121.9

137.0

158.7

72.8

84.8

95.8

106.4

116.0

128.8

1.08

1.82

1.75

1.08

98.9

118.9

98.3

119.4

0.45

1.11

73.4

85.9

95.9

104.6

113.2

122.0

90.3

101.6

112.1

124.9

137.5

157.3

75.3

68.6

97.1

107.9

116.5

129.3

1.90

1.23

1.07

1.18

99.9

118.1

99.8

117.9

0.91

0.71 I

Proximal phalanx III

Less than $3,000- $5,000- $7,000- $10,OOW $15,000

$3,000 $4,999 $6,999 $9,999 $14,999 or more

Mean skeletal age in months

72.1

85.6

94.2

10B.O

109.9

122.3

87.8

99.8

108.3

125.6

136.8

155.4

72.8

84.8

94.2

108.5

115.9

128.2

71.2

87.3

96.4

108.8

111.6

123.8

81.6

107.3

112.6

122.7

141.6

159.2

76.6

92.4

97.6

106.8

119.3

131.1

74.9

85.4

97.0

102.3

112.4

125.2

92.0

103.1

109.5

122.6

141.5

158.9

77.0

88.1

95.2

1ffi.8

119.2

131.9

Standard error of the mean

78.5

89.0

97.9

105.8

113.5

125.6

89.0

101.9

114.9

122.3

141.3

160.5

74.0

86.9

89.9

106.6

119.2

132.5

3.22 2.53 1.15 1.03

2.14 3.C6 1.89 1.43

1.87 4.34 0.90 1.93

1.75 3.84 1.65 1.52

Mean skeletal age in months

99.2

119.0

99.5

123.8

89.6 99.2

119.6 121.0

Standard erl

1.30 2,28

1.44 2.07

98.8

120.7

100.9

120.6

101.2 101.1

121.9 121.7

of the mean

1.36 0.78

1.19 1.02

79.5

90.8

97.3

107.6

115.5

124.5

91.0

101.2

113.4

125.8

141.5

160.5

76.0

86.2

98.4

109.4

119.2

132.5

1.25

1.63

1.52

0.88

101.8

122.0

101.1

122.6

0.46

1.14

80.2

89.7

100.2

107.3

115.9

124.9

95.3

105.0

116.5

129.8

142.0

161.5

80.3

90.0

101.5

111.8

119.5

133.2

1.32

1.22

1.01

1.69

103.7

123.4

102.6

121.2

0.78

0.79

76.5

91.0

99.8

109.8

112.7

126.1

91.4

102.1

112.4

129.3

142.3

160.2

76.4

87.1

97.4

111.3

119.6

132.2

2.29

2.22

2.27

1.77

103.0

123.0

102.4

122.9

1.34

1.55

76.6

90.9

100.8

109.8

116.2

125.5

94.6

108.8

112.7

129.2

144.8

163.5

79.6

94.7

97.7

111.2

121.4

134.2

1.19

2.36

4.77

3.74

103.2

127.0

102.0

124.4

2.05

2.07

68
Table 11, Mean bone-specific skeletal ages for selected hand-wrist bones of boys and girls, by annual family income and chrcmological age at last birthday, with

Standard of reference, sex, and

chronological age at

lm.t birthday

Male standard

Boys —

6yoars . . . . . . .

7 years .,,,...

8ycars, .,,...

9ycms . . . . . . .

10 years . . . . . .

llycars . . . . . .

Girls —

6 years . . . . . . .

7yt3ars, . . . . . .

8years . . . . . . .

9ycws, .,....

10years ,., ,..

11 years . . . . . .

Female equivalent

G&

6ycars . . . . . . .

7ymrs . . . . . . .

8years . . . . . . .

9yews, . . . . . .

10years ., .,..

llycws . . . . . .

Male standard

Boys —

G ears . . . . . . .

11 years . . . . . .

Girls —

6 years . . . . . . .

11 years . . . . . .

Actual VdUeS

BOVS: 6.11 yews, .

Glrls:6-llvears. ,

Expected values

BOys: 6.11 years. .

Girls: 6-11 years. .

BOvs: 6-11 years, .

Girls: 6-11 yews. .

selected standard errors: United States, 1963-65-Con.

Proximal phalanx IV’ Middle phakmx V

Less than $3,000- $5,000- $7,000- $1 o,ooC- $15,000 Less than $3,000- $5#ooo- $7#oo@ $10,000- 15,000

$3,000 $4,999 $6,999 $9,999 $14,999 or more $3,000 $4,999 $6,999 $9,999 $14,999 or more

Mean skeletal age in months

74.3

B5.2

96.9

102.4

112.B

125.4

92.0

103.2

10B.9

122.9

141.5

160.3

77.0

88.2

94.B

106.9

119.2

132.3

1.29

1.7B

0.99

1.69

96.7

120.8

101.2

122.1

1.38

1.20

77.3

89.0

9B.O

108.1

114.1

126.1

88.B

102.1

115.6

122.9

141.3

160.6

73.8

87.1

100.6

108.9

119.2

132.6

1.12

1.44

1.96

1.57

100.9

120.B

101.1

121.8

0.B4

1.06

78.8

90.4

97.5

107.6

116.0

125.4

90.8

101.7

113.3

126.0

141.9

150.8

7EuB

86.7

9B.3

109.5

119.4

132.8

1.31

1.86

1.63

0.98

78.9

89.6

100.0

107.4

116.9

125.3

95.2

104.9

117.1

129.9

142.0

161.6

BO.2

89.9

102.1

111.9

119.5

133.3

1.45

1.24

1.OB

1.65

101.B 103.7

122.2 123.5

101.1 102.7

122.7 121.3

0.46 I

0.81

1.16 0.77

75.9

91.0

100.0

109.6

113.5

126.7

91.0

102.0

113.2

129.8

142.2

159.9

76.0

B7.O

98.2

111.8

119.6

131.9

75.9

90.7

100.4

110.2

116.5

127.2

93.5

109.4

112.6

129.8

144.9

164.1

78.5

95.2

97.6

111.8

121.4

134.4

75.9

87.5

97.B

103.7

113.6

125.9

93.5

102.1

109.0

121.3

141.0

160.2

75.0

87.6

94.0

106.2

119.0

130.7

80.2

90.0

100.1

107.6

114.0

126.6

91.4

102.1

114.1

121.6

139.4

159.3

72.6

87.6

99.1

108.3

117.4

130.4

Standard error of the mean

2.44 1.25 1.46 1.40

2.11 2.15 1.36 1.62

2.16 4.57 1.24 1.50

1.57 3.70 1.68 1.73

80.4

91 .B

99.5

109.0

115.8

126.1

91.3

102.5

112.8

124.7

140.1

160.3

72.4

88.2

97.B

107.B

llB.1

130.8

1.24

1.48

1.50

0.93

Mean skeletal age in months

103.2 103.4 99.8 102.3 103.0

123.0 127.1 120.5 120.3 121.B

102.4 102.0 102.0 102.1 102.1

122.9 124.5 121.9 121.6 122.5

Standard error of the mean

B1 .0

90.6

101.4

108.0

116.7

125.5

96.9

‘104.8

116.0

131.3

141.1

161.2

80.8

90.8

101.0

112.6

119.0

131.2

1.39

1.02

1.30

1.79

104.5

123.6

103.6

121.0

1.44 2.10 1.21

1.52 *2.17 I

0.77 I

0.52 0.B7

1.42 0.97 1.11 0.81

75.3

90.9

101.0

109.6

113.6

126.5

92.2

100.3

113.4

129.7

140.4

15B.6

74.1

85.3

9B.4

111.7

11 B.4

130.2

2.48

2.22

2.13

2.01

103.2

122.6

103.4

122.8

xil75.B

90.5

99.2

111.0

114.0

127.6

87.0

109.3

113.8

128.4

146.6

165.2

B1 .0

94.3

98.8

110.7

122.3

134.2

1.65

3.03

4.81

4.09

103.1

12B.O

103.0

124.0

2.12

2.25

69
Table 12. %lected percentiles inthedistribution of theindividual child's range in bone+pecific skeletal ages fortheradio-opaque (not

adult) bones inthehand-wrist forwhite and Negro boys andgirls, bychronological ageatlasttirthday: United States, 1963-65

Standard of reference, sex, and chronological age at last birthday

Male standard

Bovs

6years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sears . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10 years . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Girls

6 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sears . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

White

I

Negro

Percentile points

75 50 25 75 50 25

Bone-specific skeletal age range in months

36.7

36.1

34.2

29.9

26.4

26.4

34.3

31.4

28.9

30.5

32.2

33.9

29.2

28.4

26.4

22.6

20.1

18.7

27.1

23.4

21.5

22.3

24.3

24.3

22.7

20.8

19.0

15.1

14.2

14.2

20.6

15.1

14.5

15.4

17.3

17.0

40.5

35.9

35.4

36.7

28.5

27.2

36.4

32.5

28.7

27.8

30.9

32.3

28.8

26.9

25.8

25.1

21.9

20.8

28.1

24.9

22.0

22.1

24.7

24.4

22.4

19.2

16.8

14.2

14.3

14.7

19.9

17.7

14.9

14.5

20.2

17.9

Table 13. Selegted percentiles in the distribution of the individual Chi[d’s range in bone-specific skeletal ages for the radio-opaque (not

adult) bones in the hand-wrist for boys and girls, by geographic region and chronological age at last birthday: United States,

1863-65

Standard of reference, sex, and

chronological age at last birthday

Male standard

Boys

6years . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . .

Girls

6years . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . .

Sears . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . .

Northeast Midwest South West

Percentile points

75 50 25 75 50 25 75 50 25 75 50 25

Bone-specific skeletal age range in months

36.7

35.6

36.6

27.7

25.5

27.1

34.4

29.7

30.1

30.2

29.4

28.9

29.2

28.3

24.1

20.5

20.3

18.6

27.8

21.8

20.9

22.2

23.1

22.6

22.1

22.0

17.6

14.8

14.3

13.6

20.1

14.7

14.3

16.2

16.6

17.2

37.4

36.3

33.5

30.3

26.1

25.5

32.5

31.4

31.3

33.2

33.5

35.8

30.2

28.3

26.6

23.8

20.3

20.1

26.9

23.6

22.6

23.9

25.8

24.9

22.1

20.3

20.3

16.1

14.3

14.5

22.4

15.4

16.2

15.4

18.6

18.6

36.5

36.7

34.9

29.6

29.3

24.5

35.7

34.7

27.7

30.1

30.4

33.1

27.4

28.3

26.2

20.3

22.4

18.7

29.3

26.6

20.8

22.7

24.9

24.7

22.5

20.4

19.6

14.2

14.9

14.4

21.8

18.5

13.6

16.2

18.8

15.7

37.0

37.4

34.3

30.6

24.8

28.3

34.4

30.2

28.6

27.0

32.6

32.8

31.0

28.3

27.6

24.1

17.9

19.4

26.4

22.3

22.2

18.5

22.6

24.2

24.3

20.8

20.2

14.8

13.3

13.3

19.9

14.2

15.4

13.9

16.0

17,4

70
Table 14. Selected percentiles in the distribution of the individual child’s range in bone-specific skeletal ages for the radio-opaque

(not adult) bones in the hand-wrist for boys and girls, by annual family income and chronological age at last birthday: United

States, 1963-65

Standard of refarence, sex, and chronological age

at Iast birthday

Male standard

Bow

6years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8yaars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

llyears .,, d o . . . . . . . . . . . . . . . . . . . . . . . . . .

Girls

6years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . . . . . . . . . . ..$.

Lessthan $5,000 $5,000-$9,999 $l0,000ormore

Percentile points

75 50 25 75 50 25 75 50 25

Bona-specific skelatal ege range in months

36.4

35.4

34.3

30.5

27.4

26.0

34.8

32.8

25.9

28.0

30.2

32.7

29.5

26.6

26.4

23. ?

20.6

19.8

27.1

24.0

19.8

21.8

23.7

24.9

23.4

20.1

19.2

14.8

14.1

14.4

20.4

16.7

12.1

15.1

17.9

18.0

38.9

36.8

36.6

30.9

30.2

29.0

34.5

31.7

28.9

32.3

32.1

34.1

30.2

29.9

27.9

23.0

22.5

21.5

27.6

24.2

20.8

23.1

24.5

23.2

22.8

21.9

20.5

16.4

16.0

15.1

20.7

16.7

14.4

15.2

16.7

17.5

36.9

41.0

34.4

30.1

25.7

26.6

33.0

31.1

28.1

29.9

34.5

32.2

28.7

30.3

26.4

23.0

20.1

18.5

27.4

18.2

20.7

21.3

24.9

24.5

22.8

22.5

20.1

14.9

14.5

13.6

23.2

12.2

14.5

16.2

18.3

16.5

Table 15, Median (chronological) age of onset of ossification in selected hand-wrist bones for boys and girls 6-11 years: United States,

1963-65

Race, ragion, and annual family income

Race

White . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Negro . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Region

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

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

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

West, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Annual family income

Lessthan $5,000. , . . . . . . . . . . . . . . . . . . . . . . . .

$5,000-$9,999. . ! . . . . . . . . . . . . . . . . . . . . . . . .

$lO,OOOormore . . . . . . . . . . . . . . . . . . . . . . . . . .

8oys I Girls

Ulna I Trapezium I Trapezoid I pitiform I F%iform I Add.ctor

7.2

7.0

7.0

7.0

7.3

7.3

7.2

7.1

7.0

6.4

4.9

6.3

6.5

6.2

6.0

6.2

6.3

6.3

Chronological age in years

6.4

6.1

6.2

6.5

6.4

6.0

6.5

6.4

6.0

11.2

11.3

11.0

11.5

11.0

11.4

11.2

11.3

11.3

8.7

8.9

8.5

8.8

8.8

8.9

8.9

8.8

8.7

10.6

10.7

10.7

10.7

10.6

10.7

10.6

10.9

10.5

71
APPENDIX I

STATISTICAL NOTES

Survey Design

The sample design for the second cycle of the

Health Examination Survey, similar to the one

used for the first cycle, was that of a multistage

stratified probability sample of loose clusters of

persons in land-based segments. Successive elements dealt with in the process of sampling are

primary sampling unit (PSU), census enumeration district (ED), segment, household, eligible

child (EC), and finally, the sample child (SC).

At the first stage, the nearly 2,000 PSU’S into

which the United Stat es (including Hawaii and

Alaska) had been divided and then grouped into

357 strata for use in the Current Population

Survey and the Health Interview Survey were

further grouped into 40 superstrata for use in

Cycle II of the HES. The average size of each

Cycle II stratum was 4.5 million persons, and all

fell between the limits of 3.5 and 5.5 million.

Grouping into 40 strata was done in a way that

maximized homogeneity of the PSU’S included

in each stratum, particularly with regard to

degree of urbanization, geographic proximity,

and degree of industrialization. The 40 strata

were classified into four broad geographic regions (each with 10 strata) of approximately

equal population and cross-classified into four

broad population den;ity groups (each having 10

strata). Each of the 16 cells contained either two

or three strata. A single stratum might include

only one PSU (or only part of a PSU, as, for

example, New York City, which represented two

strata) or several score PSU’S.

To take account of the possible effect that

the rate of population change between the 1950

and 1960 census might have had on health, the

10 strata within each region were further classified into four classes ranging from those with no

increase to those with the greatest relative

increase. Each such class contained either two or

three strata.

One PSU was then selected from each of the

40 strata. A controlled-selection technique was

used in which the probability of selection of a

particular PSU was proportional to its 1960

population. In the controlled selection, an attempt was also made to maximize the spread of

the PSU’S among the States. While not every one

of the 64 cells in the 4 X 4 X 4 grid contributes

a PSU to the sample of 40 PSU’S, the controlled

selection technique insured the sample’s matching the marginal distributions in all three dimensions and being C1OSC1y representative of all crossclassifications.

Generally, 20 ED’s were selected within a

particular PSU. The probability y of selection of a

particular ED was proportional to its population

in the age group 5-9 years in the 1960 census

which by 1963 roughly approximated the population in the target age group for Cycle II. A

similar met hod was used for selecting one

segment (clusters of households) in each ED.

Each of the resultant 20 segments was either a

bounded area or a cluster of households (or

addresses). All the children in the age range 6-11

years normally resident at each household or

address were considered EC’S. Operational considerations made it necessary to reduce the

number of prospective examinees at any one

location to a maximum of 200. The EC’s to be

excluded for this reason from the SC group were

determined by systematic subsampling.

The total sample thus selected for the examination included 7,417 children (SC’s) from 25

different States in the 6-11 year age group with

approximately 1,000 in each of the single years

of age.

72
Reliability

Measurement and assessment processes employed in the Survey were highly standardized

and closely controlled. Of course, this does not

mean that the correspondence between the real

world and the Survey results is exact. Data from

the Survey are imperfect for three major reasons: (1) results are subject to sampling error,

(2) the actual conduct of a survey never agrees

perfectly with the design, and (3) the measurement or assessment processes themselves are

inexact even though standardized and controlled.

The first report on Cycle 115 describes in

detail the faithfulness with which the sampling

design was carried out. It notes that 7,119 out

of the 7,417 sample children were examined.

This is a response rate of 96 percent. The

examined children were a highly representative

sample of this age in the noninstitutional population of the United States. The response levels

for the various demographic subgroups, including those for age, sex, race, region, population

density, parent’s educational level, and family

income, show no marked differentials. Hence, it

appears unlikely that nonresponse could have

biased the findings markedly in these respects.

Further description of the sample design and

estimation procedures are contained in a subsequent report.l68

The general measures used to control the

quality of data from this survey have been cited

previously,s Y1G$J those relating specifically to

the assessment of skeletal age are outlined in an

earlier section of this report.

Data recorded for each sample child are

inflated in the estimation process to characterize

the larger universe of which the sample child is

representative. The weights used in this inflation

process are a product of the reciprocal of the

probability of selecting the child, an adjustment

for nonresponse cases, and a poststratified ratio

adjustment, which increases precision by bringing survey results into closer alignment with

known United States population figures by color

and sex within single years of age 6 through 11.

In the second cycle of the Health Examination Survey the sample was the result of three

stages of selection—the single PSU from each

stratum, the 20 segments from each sample PSU,

and the sample children from the eligible children. The probabilityy of selecting an individual

child is the product of the probability of

selection at each stage.

Since the strata are roughly equal in population size and a nearly equal number of sample

children were examined in each sample PSU’S,

the sample design is essentially self-weighting

with respect to the target population; that is,

each child 6 through 11 years old had about the

same probabilityy of being drawn into the

sample.

The adjustment upward for nonresponse is

intended to minimize the impact of nonresponse

on final estimates by imputing to nonrespondents the characteristics of “similar” respondents.

Here “similar” respondents were judged to be

examined children in a sample PSU having the

same age (in years) and sex as children not

examined in that sample PSU.

The poststratified ratio adjustment used in

Cycle II achieved most of the gains in precision

that would have been attained if the sample had

been drawn from a population stratified by age,

color, and sex. The adjustment makes the final

sample estimates of population agree exactly

with independent controls prepared by the

Bureau of the Census for the United States

noninstitutional population as of August 1,

1964 (approximately midsurvey point), by color

and sex for each single year of age 6 through 11.

The weights of every responding sample child in

each of the 24 age, color, and sex classes is

adjusted upward or downward so that the

weighted total within the class equals the independent population control.

In addition to children not examined at all,

there were 157 for whom there was no radiograph or else the radiograph could not be

assessed. The age and sex distribution for these

157 children as well as for the 6,962 for whom

assessments were made is shown in table I. No

attempt was made to estimate the skeletal age

for this group of children without usable radiographs. Hence it is assumed that the distribution

of their skeletal ages is similar to that for the

remaining 6,962. In other words, they were

treated as if they were nonresponders.

Among the usable radiographs of the 6,962

children, there were a few in which the film

quality was not good enough to permit assess73
Table 1. Number of examined children whose hand-wrist radiographs were assessed and of those whose radiographs were

not assessed for skeletal age, by chronological age in years

and sex: Health Examination Survay, 1963-65

Radiographs Radiographs

Chronological age at assessed not assessed

last birthday

Boys Girls Boys Girls

I

Number of children

Total .,.......

r

3,545

6 years . . . . . . . . . . . . 554

7years . . . . . . . . . . . . 615

8yaars . . . . . . . . . . . . 602

9years . . . . . . . . . . . . 582

10years . . . . . . . . . . . 570

11 years . . . . . . . . . . . 622

3,417

521

602

600

562

576

556

87

21

17

16

21

6

6 r

70

15

7

13

19

8

8

ment of all ossifying or ossified bones. In

general, these would have been bones that had

become radio-opaque recently. The number of

children for whom bone-specific skeletal ages

were assessed and in which the bone was

considered as ossifying or completely ossified

(adult) is shown in table II.

Sampling and Measurement Error

In the present report, reference has been

made to efforts to minimize bias and variability

of measurement techniques.

The probability design of the Survey makes

possible the calculation of sampling errors. The

sampling error is used here to determine how

imprecise the Survey test results may be because

they come from a sample rather than from the

measurements of all elements in the universe.

The estimation of sampling errors for a study

of the type of the HeaIth Examination Survey is

difficult for at least three reasons: (1) measurement error and “pure” sampling error are

confounded in the data—it is not easy to find a

procedure that will either completely include

both or treat one or the other separately, (2) the

Survey design and estimation procedure are

complex and accordingly require computationally involved techniques for the calculation

of variances, and (3) thousands of statistics came

from the Survey, many for subclasses of the

population for which there are few cases. EstiTable Il. Number of examinad children for whom skeletal age

assessments were made on each of the 31 hand-wrist bones,

by type of bone and sex: Health Examination Survey,

1963-65

Hand-wrist bone

Radius . . . . . . . . . . . .

Ulna . . . . . . . . . . . . .

Capitata . . . . . . . . . . .

Hamate . . . . . . . . . . . .

Triquetral. . . . . . . . . . .

Lunate . . . . . . . . . . . .

Scaphoid . . . . . . . . . . .

Trapezium . . . . . . . . . .

Trapezoid . . . . . . . . . .

Metacarpal I . . . . . . . . .

Metacarpal Il. . . . . . . . .

Metacarpal Ill . . . . . . . .

Metacarpal IV . . . . . . . .

Metacarpal V . . . . . . . .

Proximal phalanx I . . . . .

Proximal phalanx I I . . . . .

Proximal phalanx Ill . . . .

Proximal phalanx IV . . . .

Proximal phalanx V . . . . .

Middle phalanx II . . . . . .

Middle phalanx 1I I . . . . .

Middle phalanx IV . . . . .

Middle phalanx V . . . . . .

Distal phalanx I . . . . . . .

Distal pha]anx II . . . . , . .

Distal phalanx Ill . . . . . .

Distal phalanx IV . . . . . .

Distal phalanx V . . . . . .

Pisiform . . . . . . . . . . .

Adductor sesamoid . . . . .

Flexor sesamoid . . . . . . .

Number of children

3,540

2,806

3,540

3,540

3,518

3,448

3,161

3,046

3,180

3,538

3,541

3,542

3,542

3,542

3,539

3,542

3,543

3,543

3,543

3,538

3,536

3,538

3,526

3,533

3,532

3,531

3,532

3,532

746

88

21

1 In long and short bones, “radio-opaque” refers to the

3,417

3,201

3,375

3,387

3,322

3,363

3,352

3,311

3,338

3,409

3,4~1

3,411

3,411

3,410

3,407

3,410

3,410

3,406

3,406

3,405

3,411

3,410

3,388

3,371

3,380

3,383

3,387

3,382

1,789

837

321

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

26

24

62

25

19

32

32

6

3

3

3

3

6

4

4

7

8

4

2

2

6

18

19

20

18

17

s

9

6

epiphyses.

mates of sampling error axe obtained from the

sample data and are themselves subject to

sampling error, which may be large when the

number of cases in a cell is small or occasionally

even when the number of cases is substantial.

Estimates of approximate sampling variability

for selected statistics used in this report are

presented in the detailed tables. These estimates

have been prepared by a replication technique

74
that yields overall variability through observation of variability among random subsamples of

the total sample. The method reflects both

“pure” sampling variance and a part, of the

measurement variance.

In accordance with usual practice, the interval

estimate for any statistic may be considered the

range within 1 standard error of the tabulated

statistic, with 68-percent confidence, or the

range within 2 standard errors of the tabulated

statistic, with 95-percent confidence. The latter

is used as the level of significance in this report.

An approximation of the standard error of a

difference d = x - y of two statistics x and y is

given by the formula Sd = (% + S$)%, where

SX and SY are the sampling errors, respectively,

ofx andy.

(i =12, , . . . . ,6; %i = n) and the estimates of

mean skeletal age for all U.S. boys in the Zthage

group to be ~i, then the expected mean skeletal

age for boys in that area is:

The specific area may have higher values for

younger boys and lower values for older boys

than in the other areas. In that case the expected

average may obliterate one or both of these

differentials. These types of limitations need to

be kept in mind in interpreting these data. The

standard error of the difference between an

actual and an expected mean value may be

approximated by the standard error of the

actual value.

Expected Values

Small Categories

In the detailed tables both the actual and

expected mean skeletal ages are shown for

children in the various demographic groups. The

expected mean values are obtained by assuming

that the national age-specific mean values apply

within the appropriate age subgroup for which

the value is derived.

For example, if in an area (e.g., the Northeast) estimates from the Health Examination

Survey show ni boys in the Z%hage group

In some tables, magnitudes are shown for cells

for which the sample size is so small that the

sampling error may be several times as great as

the statistic itself. Obviously in such instances

the statistic has no meaning in itself except to

indicate that the true quantity is small. Such

numbers, if shown, have been included in the

belief that they may help to convey an impression of the overall story of the table.

000

75
APPENDIX II

DEMOGRAPHIC AND SOCIOECONOMIC TERMS

Age. –The age recorded for each child was the

age at last birthday on the date of examination.

The age criterion for inclusion in the sample

used in this survey was defined in terms of age at

time of interview. Since the examination usuaIly

took place 2-4 weeks after the interview, some

of those who were 11 years old at the time of

interview became 12 years old by the time of

examination. There were 72 such cases. In the

adjustment and weighting procedures used to

produce national estimates, these 72 were included in the 1l-year-old group.

Race. –Race was recorded as “white,”

“Negro,” or “other. “ “Other” included American Indians, Chinese, Japanese, and aIl races

other than white or Negro. Mexican persons

were included with “whit e“ unless definitely

known to be American Indian or of other

nonwhite race. Negroes and persons of mixed

Negro and other parentage were recorded as

“Negro.”

Geographic rep-on. –For purposes of stratification, the United States was divided into four

broad geographic regions of approximately equal

population. These regions, which correspond

closely to those used by the Bureau of the

Census, were as follows:

Rep”on

Northeast . . . . . .

Midwest . . . . . .

States included

Maine, Vermont, New

Hampshire, Massachusetts,

Connecticut, Rhode Island,

New York, New Jersey, and

Pennsylvania.

Ohio, Illinois, Indiana,

Michigan, Wisconsin, Minnesota, Iowa, and Missouri

South . . . . . . . . . Delaware, Maryland, District of Columbia, West Virginia, Virginia, Kentucky,

Tennessee, North Carolina,

South Carolina, Georgia,

Florida, Alabama, Mississippi, Louisiana, and Arkansas.

West . . . . . . . . . Washington, Oregon, California, Nevada, New Mexico, Arizona, Texas, Oklahoma, Kansas, Nebraska,

North Dakota, South Dakota, Idaho, Utah, Colorado, Montana, Wyoming,

Alaska, and Hawaii.

Urban-rural.-The definition of urban-rural

areas was the same as that used in the 1960

Census. According to this definition, the urban

population was comprised of all persons living in

(1) places of 2,500 inhabitants or more incorporated as cities, boroughs, villages, and towns

(except towns in New England, New York, and

Wisconsin); (2) the densely settled urban fringe,

whether incorporated or unincorporated of

urbanized areas; (3) towns in New England and

townships in New Jersey and Pennsylvania that

contained no incorporated municipalities as subdivisions and had either 2,500 inhabitants or

more, or a population of 2,500 to 25,000 and a

density of 1,500 persons or more per square

mile; (4) counties in States other than the New

England States, New Jersey, and Pennsylvania

that had no incorporated municipalities within

their boundaries and had a density of 1,500

persons or more per square mile; and (5)

unincorporated places of 2,500 inhabitants or
more not included in any urban fringe. The

remaining population was classified as rural.

Urban areas are further classified by population size for places within urbanized areas and

other urban places outside urbanized areas.

Grade in schooL-The grade that the child

attended at the time of the interview was used

here and later verified against school records.

The grade of those children on summer vacation

was considered to be the grade that they would

enter when school resumed.

Education of parent or guardian.–This was

recorded as the highest grade completed in

school. The only grades counted were those

attended in a regular school where persons were

given formal education in graded public or

private schools, whether day or night school,

and whether attendance was full or part time. A

“regular” school is one that advances a person

toward an elementary or high school diploma, or

a college, university, or professional school

degree. Education in vocational, trade, or business schools outside the regular school system

was not counted in determining the highest

grade of school completed.

Family income. –The income recorded was

the total income of the past 12 months received

by the head of the household and all other

household members related to the head by

blood, marriage, or adoption. This income was

the gross cash income (excluding pay in kind)

except in the case of a family with their own

farm or business, in which case net income was

recorded.

Parent.–A parent was the natural parent or,

in the case of adoption, the legal parent of the

child.

Guardian.–A guardian was responsible for the

care and supervision of the child. He or she did

not have to be the legal guardian to be considered the guardian for this survey. A guardianship

could only exist when the parent(s) of the child

did not reside within the sample household.

Head of household. –Only one person in each

household was designated as the “head.” He or

she was the person who was regarded as the

“head” by the members of the household. In

most cases, the head was the chief breadwinner

of the family, although this was not always true.

In some cases, the head was the parent of the

chief earner or the only adult member of the

household.

000

77
APPENDIX HI

RELIABILITYOF ASSESSMENTS

To provide the basis for determining the level

of reliability of the bone-specific skeletal age

assessments made by the six medical students at

Case Western Reserve University from handwrist radiographs of the 6- to 1l-year-old children examined in the Health Examination Survey of 1963-65, a randomly selected sample of 1

in 24 films was reassessed by the same reader

and approximately 1 in 24 independently randomly selected films was reassessed by another,

as described previously. All six readers, before

starting these final assessments, had been trained

by Dr. Pyle in the Greulich-Pyle method using

the HES Standard to the point that their ratings

were in close agreement with hers. In all, 297

self-replicate assessments and 288 cross-replicate

assessments were obtained. Thus, each reader

made approximately the same number of selfand cross-replicate assessments.

All six readers maintained a high level of

consistency in their own assessments throughout

all 40 stands of examinations in the Survey. The

mean difference in self-replicate assessments for

all six readers combined was 0.8 month for all

31 bones and just slightly less–O.7 month–if the

bones that are late to ossify (the pisiform,

adductor sesamoid, and flexor sesamoid) are

excluded. Considering data from all 31 bones,

the mean difference per reader between his

original and self-replicate assessment ranges from

0.0 to 1.4 months (combining data for the two

sexes). For the 28 bones that ossify relatively

early, the mean differences ranged from 0.0 to

1.5 months among the six readers (table III).

A consistently high level of agreement in

bone-specific skeletal age assessments was also

maintained among the 6 readers but the level

was, as expected, somewhat lower than that for

the individual readers with themselves. On all 31

hand-wrist bones, the mean cross-replicate differences between the original and the replicate

assessment by another reader was 0.0 months. It

ranged between +1.4 and i-3.6 months for three

of the readers and –1.2 to –3.3 for the other

three readers. When only the 28 centers that

ossify relatively early are considered, the overall

mean difference was nearly identical to that for

all 31 bones (table IV).

A further independent test of the validity and

reliabilityy of the skeletal age assessments in this

study was made on a randomly selected group of

50 hand-wrist radiographs among the 1l-yearold boys in the national study. These 50 films

were reassessed independently by an assesso~ at

Fels Research Institute who was proficient in

the use of the Greulich-Pyle method but had not

been trained by Dr. Pyle. The assessor at FeLs

Institute was not told the age or sex of the

children nor did she have access to the previous

skeletal age assessments. Her mean skeletal age

(hand-wrist) for the 50 radiographs was 0.7

month lower than the original assessment for

them in the national study. Her mean bonespecific skeletal ages ranged from 3.6 months

greater on the scaphoid to 2.9 months less on

the ulna than the original assessments (table V).

The aspects considered include consistency

within observers (intraobserver differences),

comparabilityy between observers (int erobsewer

differences), and differences resulting from vari78
Tabla II1. Mean difference in cross-and salf-replicate assessmentsof bone-specific skaletal agesfrom hand-wrist radiographs of axaminaes

of chronological agas 6-11 years (at last birthday), by reader: Health Examination Survey, 1963-65

Assessor

Self-replicate I Cross-raplicate Type

of

replication Range in mean

differences

Averaga mean

difference

==I==

Range in mean

diffarencas

31 bonas 28 bones’

Average mean

difference

1

31 bonas I 28bones1 31 bones 28 bonas’ Cross I Self

Number of

Both sexas Months of skelatal age bonas assessad

Assassor1,; .

Assessor2.. .

Assessor3.. .

Assassor4.. .

Assessor5.. .

Assessor6.. ,

Bovs

0.0

0.3

0.7

0.6

0.7

1.5

0.2

0.1

0.7

0.8

0.9

1.2

0.0

0.4

0.6

0.4

0.6

1.7

0.7-10.7

0.04-10.5

0.03-5.6

0.1-13.1

0.1-7.0

0.2-5.1

0.6-10.7

0.03-7.5

0.3-5.5

0.1-6.7

0.1-6.5

0.7-5.1

0.2-5.5

0.6-10.5

0.3-5.6

1.6-13.1

0.2-7.0

1.0-3.8

724

1,771

2,130

970

1,395

1,415

360

932

1,063

461

502

663

364

839

1,067

508

893

552

0.0-1.8

0.0-7.0

0.1-3.0

0.1-2.4

0,1-4.7

0.6-3.6

0,1-1.8

0.0’7.0

0.1-3.0

0.02.1

0.1-4,7

0,1-3.5

0.0-1.0

0.03-1.7

0.1-1.6

0.1-2.4

0,1-2.7

0.6-3.6

0.0-1.8

0.0-2.5

0.1-2.1

0.1-2.4

0.1-4.7

0.6-3.6

0.1-1.8

0.0-2.5

0.1-2.1

0.0-2.1

0.14.7

0.1-3.5

0.0-0.9

0.03-1.7

0.1-1.6

0.1-2.4

0.1-2.7

0.6-3.6

0.0

0.3

0.7

0.6

0.7

1.4

0.2

0.3

1.3

0.4

1.0

1.6

0.0

0.3

0.8

0.8

0.5

0.8

0.7-10.7

0.04-7.5

0.03-5.6

0.1-7.7

0.1-6.3

0.2-5.1

o.6-i 0.7

0.03-7.5

0.3-5.5

0.1-6.7

0.1-6.3

0.7-5.1

0.2-5.5

0.6-5.5

0.3-5.6

1.6-7.7

0.2-5.6

1.0s3.8

3.6

2.9

–2.2

–1 .2

-3.3

1.4

3.8

2.8

-2.5

-1.0

-3.6

1.7

3.3

2.9

–2.0

-1.4

-3.9

1.2

3.7

2.9

-2.2

-1.3

-3.2

1.5

3.9

2.6

-2.5

-1.4

–3.0

2.0

3.5

3.3

-2.0

-1.2

-3.9

1.1

758

1,694

1,869

936

1,283

1,597

384

869

869

477

710

612

374

825

980

459

583

985

Assassor1.. .

Assessor2.. .

Assessor3.. .

Assessor4.. .

Assessor5, . .

Assassor6.. .

Girls

Assessor1.. .

Assassor2, . .

Assessor3.. .

Assessor4.. ,

Assessor5.. .

Assessor6.. .

i Excluding the pisiform and adductor and flaxor sesamoids.

ations in the way the GreuIich-Pyle Atlas has Unfortunateely, the suggestionbyMoorel70 that

been used. This review is restricted to reports

based on samples of at least 10 radiographs and

to the chronological age range 6-11years.

While it is impossible to determine the true

maturity level of the bones visualized in a

radiograph, the reliability of assessments should

be defined both within and between observers.

As stated by Greulich and PyleG:

. .

sets of duplicate radiographs that have been

assessed by recognized experts be available to

those who wish to measure their level of

comparabilityy has not been implemented.

Area Skeletal Ages

It is not easy to compare reported findings

because workers have analyzed their data in

different ways. For intraobserver differences,

95-percent confidence limits of ‘7.2monthsl71

and mean differences ranging from 1.2 to 6.6

Though the ability to duplicate assessments with a good

degree of consistency must be possessed by a competent

assessor, it afone is not enough. It is even more important

that the assessments be made correctly, that is, that they be

made accordhg to the method recommended by the particular radiographic atlas on which they purport to be based.

79
Table IV. Mean differences in cross- and self-replicate assessments of bone-specif ic skeletal ages from hand-wrist radiographs of examinees of chronological ages 6-11 yaars (at last birthday), by bone: Health Examination Suwey, 1963-65

Hand-wrist bone

Radius . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Ulna . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Capi~ate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Hamate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Triwetral . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Lunata . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Scaphoid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Trapezium . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Trapezoid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Metacarpal I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Metacarpal 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Metacarpal ill . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Metacarpal IV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Metacarpal V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Proximal phalanxl . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Proximal phalanxll . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Proximal phalanx ill . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Proximal phalanx lo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Proximal phalanxV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Middlephalanx lo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Middlaphalanx Ill . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Middlephalanx lo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Middlephalanx V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Distal phalanx l . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Distal phalanx ii . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Distal phalanx ill . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Distal phalanxlV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Distal phaIanxV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

pisiform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Adductorsesamoid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Flexorsesamoid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Self-raplicate

=Jl_=l=

0.8

0.3

0.2

0.4

1.2

0.1

0.2

0.3

0.4

0.9

1.0

0.6

0.7

0.7

0.8

0.3

0.4

0,8

0.4

0.6

0.5

0.5

0.9

0.2

0.4

0.6

0.7

0.5

0.3

0.5

0.4

Cross-replicate

*

Months of skalatal age

,’0.4

0.2

0.5

0.3

1.6

0.0

0.2

0,2

0.5

1.0

1.1

0.7

0.8

0.9

0.5

0.2

0.3

0,9

0.5

0.8

0.7

0.7

1.0

0.5

0.5

0.5

0.9

0.7

0.4

0.2

0.3

0.9

0.3

0.2

0.5

0.6

0.2

0.2

0.3

().4

0.9

1.1

0.7

0,7

0.6

1.2

0.4

0.6

0.7

0.4

0.5

0.3

0.3

0,8

0.2

0.3

0.6

0.6

0.4

0.2

0.4

0.6

0.0

0.0

0.0

0.1

0.0

0.5

0.1

0.3

0.0

0.0

0.6

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

3.6

0.1

0.0

0.0

0.0

0.0

0.6

0.0

0.5

0.1

0.0

0.7

1.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.1

0.0

0.1

0.1

0.1

0.0

0.1

0.0

0.0

0.1

0.1

0.2

0,1

0.4

0.2

0.2

0.0

0.1

0.6

0.1

0.1

0.1

0.1

0.1

0.1

0.1

0.1

0.1

0.1

0.1

0.0

0.l

0.0

0.0

0.0

0.1

0.0

0.0

3.6

months have been re~orted8~17z-175 in addi- armears iustified. Re~orted mean interobserver

tion to variable &rors of 1.4 to 4.2

months.lTG,lTT The median intraobserver differences range from zero to4months.1 78-180A

report of zero median differences seems surprising at first but it is possible because Moed and

his coworkers made overall assessments to the

nearest atlas standard. The reliability of theHES

data compare favorably with the preceding.

Todd’s 18 claim that interobserver differences

less than 6 months could be achieved readily

d’;ffere;ces rang; from 1.3 to 4.2

months.8j181>182 In addition, a root mean

square of 6.2 months and confidence limits of

7.4 months have been reported} 71~lT5 Reported incidence of particular interobserver

differences indicate that the medians were less

than 3 months for the study by Hansman and

Maresh183 and lessthan 6monthsfor the study

by Moed et al.178 The mean interobserver

differences among readers in th; national sur80
Tabla V. Mean difference on 50 radiographs of 1l-year-old

boys between original assessmentsat Case Westarn Reserve

University and reassessment at Fels Research Laboratory:

Health Examination Suwey, 1963-65

Hand-wrist bone

Total . . . . . . . . . . . . . .

Radius, . . . . . . . . . . . . . . . .

Ulna, . . . . . . . . . . . . . . . . . .

Cavitate . . . . . . . . . . . . . . . .

Hamate, ., .,, ..,...... . .

Triquetral. . . . . . . . . . . . . . .

Lunate . . . . . . . . . . . . . . . . .

Scaphoid, . . . . . . . . . . . . . . .

Trapezium, . . . . . . . . . . . . . .

Trapezoid . . . . . . . . . . . . . . .

Metacarpal I . . . . . . . . . . . . . .

Metacarpal 11. . . . . . . . . . . . . .

Metacarpal ill, . . . . . . . . . . . .

Metacarpal IV . . . . . . . . . . . . .

Metacarpal V, . . . . . . . . . . . . .

Proximal p.lanx l........ . .

Proximal phalanxll. . . . . . . . . .

Proximal phalanxlll . . , . . . . . .

Proximal phalanxlV . . . . . . . . .

Proximal phalanx V, , . . , . . . . .

Middle phalanx lo, . . . . . . . . . .

Middle phalanx ill. . . . . . . . . . .

Middle phalanx IV, , . . . . . . . . .

Middlaphalanx V .,, . . . . . . . .

Distal phalanx l . . . . . . . . . . . .

Dk.telphalanx lo, . . . . . . . . . . .

Distal phalanxlll . , . . . . . . . . .

Distal phalanx lo . . . . . . . . . . .

Distal phalanx V., . . . . . . . . . .

Pisiform, . . . . . . . . . . . . . . . .

Adductor sesamoid , . . . . . . . . .

Flexor sesamoid . . . . . . . . . . . .

Mean difference

Skeletal age in months

–0.7

–0.1

–2.9

–2.8

–1.6

+0.9

+1.0

+3.6

+1.7

+0.9

+1.4

+0.3

+0.5

0.0

–0.3

–1.3

–2.6

–1.2

–1.5

–1.5

+0.9

–0.3

–1.7

-0,7

+1.2

–1.6

–1 .9

-1.6

–2.0

-2.6

–0.5

-.

vey are toward the lower end of the sample

values reported by others.

BoneSpecific Skeletal Ages

Few have reported relevant data. The intraobserver differences were almost all less than 3

months in the study of Sproul and Peritz.l80

Moorel70 reported interobserver differences

that were less than 12 months in 94 percent of

bones.

Factors Influencing Replicability

There is no indication that the level of

replicability is related to the difference between

chronological and skeletal age.l 73~176 However,

the range of maturity between the bones of a

hand-wrist influences the replicability of overall

but not bone-specific assessments.8~173 The

quality of the radiographs (exposure, positioning) has no effect on replicability within the

range usual in research studies,* but unusually

poor radiographic quality does reduce replicability.l 76 The method by which the Greulich-Pyle

Atlas is used has an effect. Mareshz3 reported a

technical error of 3.0 months between overall

assessments and those obtained as the means of

bone-specific skeletal ages. The direction of

these differences was not reported. Peritz and

Sprou177 considered assessment more difficult

in short or tall children and in the hamate and

second metacarpal than in other hand-wrist

bones. The latter statement has not been confirmed in the Health Examination Survey on

either self- or cross-replication data.

000

~ U. S. GOVERNMENT PRINTRiG OFFICE : 1975 .?10-981tL?

81
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