Data from the

NATIONAL HEALTH SURVEY

Total Serum

Cholesterol Values

of Youths 12-17 Years

United States

Serum cholesterol values are presented and discussed by age, sex,

race, and socioeconomic level of youths 12-17 years of age in the

United States, 1966-70.

DHEW Publication No. (H RA) 76-1638

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

Public Health Service

Health Resources Administration

National Center for Health Statistics

Ro,ckville, Md. May 1976

Series 11

Number 156
Library of Congress Cataloging in Publication Data

Main entry under title:

Total serum cholesterol values of youths 12-17 years, United States.

(Vital and health statistics: Series 11, Data from the National Health Survey, Data

from the health examination survey; no. 156) (DHEW publication no. (HRA) 76-1 638)

Includes bibliographical references.

Supt. of Dots. No.: HE 20.6209:11/156

1. Youth–Health and hygiene–United States–Statistics. 2. Blood cholesterol.

3. Health surveys–United States. I. Levy, Paul S. II. 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. 156. III. Series: United States, Dept.

of Health, Education, and Welfare. DHEW publication; no. (HRA) 76-1 638) [DNLM:

1. Cholesterol–Blood. 2. Blood chemical analysis-In adolescence. W2 N148vk no. 156]

RA407.3.A347 no. 156 [RA564.5] 312’.0973s [612’.12] ISBN 0-8406-0051-875-619260
NATIONAL CENTER FOR HEALTH STATISTICS

DOROTHY P. RICE, Director

ROBERT A. ISRAEL, Deputy DireckxJACOB J. FELDMAN, Ph.D., Associate DirectorforAna@is

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

ELIJAH L. WHITE, Associate Director for Data Systems

GEORGE P. FAILLA, Associate Director for Management

PETER L. HURLEY, Associate Director for Operations

JAMES M. ROBEY, Ph.D., Associate Director for Program Deveibpment

ALICE HAYWOOD, Information Officer

DIVISION OF HEALTH EXAMINATION STATISTICS

ARTHUR J. McDOWELL, Director

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

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

JEAN ROBERTS, Chiej Medical Statistics Branch

ROBERT MURPHY, Chief Survey Planning and Development Branch

Vital and Health Statistics-Series 1l-No. 156

DHEW Publication No. (HRA) 76-1638

Library of Congress Catalog Card Number 75-619260
CONTENTS

Introduction . . . . . . . .

Method . . . . . . . . . . .

Race . . . . . . . . . . .

Blood Specimen and Total

Findings . . . . . . . . . .

Age and Sex . . . . . . .

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

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

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

Serum Cholesterol Determination

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

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

Geographic Region, Age, and Sex . . . . . . . . . . . . .

Race, Age, and Sex . . . . . . . . . . . . . . . . . . . .

Annual Family Income, Education of Parent, Age, and Sex

Discussion . . . . . . . . . . . . . . . . . . . . . . . . . .

Age and Sex . . . . . . . . . . . . . . . . . . . . . . . .

Race . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Annual Family Income . . . . . . . . . . . . . . . . . .

Other Studies . . . . . . . . . . . . . . . . . . . . . . .

References . . . . . . . . . . . . . . . . . . . . . . . . . .

Listof Detailed Tables . . . . . . . . . . . . . . . . . . . .

Appendix I. Technical Notes on Methods . . . . . . . . . .

The Survey Design . . . . . . . . . . . . . . . . . . . . .

Some Notes on Response”Rates . . . . . . . . . . . . . .

Parameter and Variance Estimates . . . . . . . . . . . . .

Standards of Reliability and Precision . . . . . . . . . . .

Imputation . . . . . . . . . . . . . . . . . . . . . . . .

Appendix II. Demographic Variables . . . . . . . . . . . . .

.

.

.

.

.

.

.

.

.

.

.

.

.

.

Appendix III. Techniques of Measurement and Quality Control

Measurement . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . .

The HES Blood-Drawing Technique and Its Historical Development . . . . . .

Cholesterol Chemistry Determinations . . . . . . . . . . . . . . . . . . . . .

Monitoring Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Methods of Taking Replicate Measurements . . . . . . , . . . . . . . . . . .

Results of the Replicate Study for Cholesterol . . . . . . . . . . . . . . . . .

Data Handling Verification . . . . . . . . . . . . . . . . . . . . . . . . . .

Page

1

2

2

3

3

3

4

4

5

6

7

9

10

10

11

13

26

26

27

28

29

29

30

31

31

31

32

32

33

33

35
SYMBOLS

I

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

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

I

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

I

I

Quantity more than Obut less than 0.05---- 0.0

Figure does not meet standards of

reliability or precision ----------------------------

*
TOTAL SERUM CHOLESTEROL VALUES

OF YOUTHS 12-17 YEARS

Paul S. Levy, SC.D., Peter V. V. Hamill, M.D., M.P.H., Felix Heald, M.D., and Michael Rowlanda

INTRODUCTION

This report of serum cholesterol values as

determined from blood samples of youths 12-17

years of age in the United States is one of a

series of reports presenting findings from Cycle

III of the Health Examination Survey (HES).

The means and selected percentiles of total

serum cholesterol values are examined here by

sex, age, race, family income, education, and

geographic location in the United States. As

described in a detailed report of its general plan

and operation, 1 the Health Examination Survey

is conducted in a succession of cycles.

Cycle I of the HES, conducted from 1959 to

1962, obtained information on the prevalence’ of

certain chronic diseases and on the distribution

of a number of anthropometric and sensory

characteristics in the civilian, noninstitutionalized population of the continental United

States aged 18-79 years. The detailed plan of

Cycle I has been described,z and most of the

results are published in other reports in Series 11

of Vital and Health Statistics.

Cycle II of the HES, conducted from July

1963 to December 1965, involved selection and

examination of a probability sample of noninstitutionalized U.S. children aged 6-11 years. This

program succeeded in examining 96 percent of

the 7,417 children selected for-the” sample. The

‘AssociateProfessorof Biometry,Universityof Wlnok,

School of Public Health; Medlcaf Adviser, Children and Youth

Programs, Division of Health Examination Statistics; Professor of

Pediatrics, D]rector, Division of Adolescent Medicine, University

of Maryland, School of Medicine; Analytical Statistician,

Division of Health Examination Statistics, respectively.

examination had two focuses: (1) factors related

to healthy growth and development as determined by a physician, a nurse, a dentist, and a

psychologist and (2) a variety of somatic and

physiologic measurements performed by specially trained technicians. The detailed plan and

operation of Cycle II and the response results

are described in Vital and Health Statistics,

Series l-Number 5.3

HES Cycle III, conducted from March 1966

to March 1970, was essentially an agewise extension of Cycle II into adolescence. As described

in detail in “Plan and Operation of a Health

Examination Survey of U.S. Youths, 12-17

Years of Age,”h Cycle III was more similar to

Cycle II than to Cycle I not only in form,

content, and style but also in having its major

emphasis on factors of “normal” growth and

development rather than on chronic diseases.

These analyses on “normal” growth and development of adolescents have been well underway

since 1970, and some of the results from the

battery of body measurements have already

‘ been published,s ‘T as have the initial results of

the hematocrit findingsg and the serum uric acid

values.g

The present report of cholesterol values is the

third in the series presenting findings from the

sample of blood drawn from each youth. No

blood specimens were obtained from children in

Cycle II, but specimens were obtained from the

adults in Cycle I.

The information from the analysis of blood is

intended for use as much needed reference data

both for clinical and for epidemiologic estimates”

of variation in a well-defined population. It also
enables examination of another aspect of growth

and development during adolescence. The procedure by which the Division of Health Examination Statistics obtained advice on the selection

of the analyses to be made on the blood specimens and the cooperative arrangements which

were subsequently made with the Lipid Standardizatipn Laboratory of the Center for Disease

Control (CDC) have been described elsewhere.A

The authors and the Division of Health

Examination Statistics are grateful for the technical advice given by Dr. Gerald Cooper, Dr.

Myron Kuchmak, and Dr. Alan Mather and for

their administrative assistance in arranging the

laboratory determinations that were performed

by the Lipid Standardization Laboratory at

CDC, and to Mrs. Margie Sailors for coordination and verification of the laboratory data and

its transmission.

METHOD

At each of 40 preselected locations (see

appendix I for sample design) throughout the

United States, the youths were brought to the

centrally located mobile examination center for

an examination that lasted about 3% hours. Six

youths were examined in the morning and six in

the afternoon. Except during vacations, they

were transported to and from school and/or

home.

When the youths entered the examination

center, their oral temperatures were taken, and a

cursory screening for acute illness was made; if

illness was detected, the youth was sent home

and reexamined later. The examinees changed

into gymnasium-t ype shorts; cotton sweat socks;

a terry-cloth robe; and, for the girls, a light,

sleeveless topper. All six then proceeded to

different stages of the examination, each one

following a different route. The 3?4-hour examination was divided into six 35-minute time

periods, each consisting of one or more detailed

examinations at a designated station. At the end

of each period, the youths rotated to other

stations, so that at the end of 3% hours each

youth had been given essentiality the same

examinations by the same examiners, but in a

different sequence. Four of these examination

time periods were allocated to examinations by

a pediatrician, a dentist, and a psychologist,b

and the other two were allocated to a group of

examinations performed by highly trained technicians. This last group of examinations consisted of X-rays of the chest and hand-wrist,

hearing and vision tests, measures of respiratory

function, a 12-lead electrocardiogram, a submaximal exercise tolerance test on a treadmill

with chest leads to a continuous electrocardiogram, a battery of body measurements, grip

strength measurements, examination of blood

and (on girls only) urine cultures for bacteria,

and a privately administered health behavior and

health attitude questionnaire.

Race

Race was recorded as “white,” “Negro,” and

“other races’” (see appendix II). In Cycle III,

white youths constituted 84.74 percent of the

total youths examined; Negro youths, 14.76

percent; and youths of other races, only 0.50

percent. In Cycle II, white children constituted

85.69 percent of the examined subjects and

Negro children, 13.86 percent. (The differential

response rate by age, sex, and race is analyzed

and discussed in appendix I. The increased

proportion of Negro subjects in Cycle 111was

bThe entire examination by the psychologists consisted of

two consecutive time periods (70 minutes). Two psychologists

performed identical examinations simultaneously at separate

stations.

“rhe same classification scheme as used in the 1960 census

was employed here. As described in the previously mentioned

report on the operation of HES Cycle 111,4 this information was

obtained at the initial household interview by the U.S. Bureau of

the Census fieldworker. The accuracy of the information was

checked at the subsequent home visit by the highly experienced

representative from HES and again at the examination in the

@roller. A final record check by birth certificate turned up only

seven inconsistencies, and these were mostly pertaining to the

category “other races,” Hence, the possible extent of misclassification of the race variable, as described, is so minimal that it

could have no effect on the data analyzed in this report.

However, when comparing the present HES findings to those of

other variouply defined racial groupings in the world, the degrees

of genetic admixture, as first discussed by Herskowitsl Oin 1928

and later by Glass and U, 11 by Robertsjl 2 Roberts and

Hioms, la and by Reed14 should be taken into consideration.
due to their better response rate–the overall

Negro response rate wa~ 96.6 percent and the

overall white response rate was 89.1 percent.) As

in Cycle II, because so few youths of “other

races” were part of the sample, data for them

have not been analyzed as a separate category.

Whenever data are analyzed independently of a

classification by race, however, data for these

youths are included.

Blood Specimen and Total Serum

Cholesterol Determination

The analyses for total serum cholesterol (i.e.,

both free cholesterol and esterified cholesterol)

were performed for the Health Examination

Survey at the Lipid Standardization Laboratory

of the Center for Disease Control; Public Health

Service, Atlanta, Ga.. There, a semiautomated

procedure was employed using the Abell-Kendall

method,l 5 details of which are presented in

appendix III. This method, with a specificity y for

total cholesterol of 99 percent, is considered an

accurate measure of total cholesterol. 1s>1G It

has the additional advantage of being used in

most of the controlled studies on the role of

cholesterol in heart disease, as it yields high

comparability y.

The development of the technique used by

the HES for obtaining and processing the blood

specimen is also described in appendix III. As

described in the two previous reports,s ‘g the

microhematocrit was the only complete laboratory determination performed on the blood

specimen directly in the examination trailers.

The bulk of each blood specimen, after preliminary laboratory preparation, was properly

separated into its various subsamples and packed

into specially devised styrofoam containers for

shipment via air freight to either the Immunogenetics Laboratory of The Johns Hopkins University, Baltimore, Md., or the Center for Disease

Control in Atlanta, Ga.

A frozen specimen for the total serum cholesterol was shipped directly to the Clinical Chemistry Section of the Center for Disease Control

for analysis. A specimen of clotted blood was

sent directly to the Venereal Disease Research

Laboratory of the CDC for analysis.

FINDINGS

Age and Sex

The estimated number and percent distribution of male and female youths 12-17 years of

age falling into each of 19 groups according to

their levels of cholesterol are shown in tables 1

and 2, respectively. The patterns shown in these

distributions are discussed below in terms of a

few summary statistics.

The estimated mean cholesterol levels for

each of the 12 age-sex classes are shown in table

3 and figure 1. Among male youths 12-17 years

of age, mean cholesterol levels were highest in

12-year-olds (181.3 mg/100 ml), decreased in

the next two age groups (174.7 mg/ 100 ml in

13-year-olds and 169.9 mg/100 ml in 14-yearolds), and remained relatively stable in the next

three age groups. The mean cholesterol levels of

females aged 12-16 ranged from 175 to 178

mg/ 100 ml; but for 17-year-olds, however, the

mean level was 184.5 mg/ 100 ml—indicating a

rise of more than 6 mg/100 ml from 16 to 17

years of age. With the exception of 12-year-olds,

200

F=

.- - —------------ —------------

— Male

---- Female

“12 13 14 15 16 17

AGE IN YEARS

Figure 1. Mean cholesterol levels for youths 12-17 years of age,

by age and sex: United States, 1966-70.

3
females in each age group had higher mean

cholesterol levels than males in the same age

group.

Percentiles of the cholesterol distributions are

shown by age for male and female youths (table

3 and figure 2). For each age-sex group, the

mean cholesterol level was always greater than

the median, which indicates that the cholesterol

distribution was skewed to the right (positive

skewness). This skewness was most pronounced

in 17-year-old females for whom the mean

cholesterol level was 5.3 mg/ 100 ml greater than

the median. The age patterns described above

for the mean were also apparent when percentiles at both the upper and lower ends of the

distribution were examined.

Geographic Region, Age, and Sex

Mean cholesterol levels are shown by age and

sex for the four geographic regions defined in

the Health Examination Survey in table 4 and

figure 3. In general, mean cholesterol levels were

highest in the Northeast, and there were few, if

any, differences in mean cholesterol levels

among the other three regions.

Race, Age, and Sex

The estimated number and percent distribution of white and Negro youths falling into each

of 19 groups according to their cholesterol levels

are shown, respectively, in tables 5, 6, 7, and 8.

Patterns observed in these distributions are discussed below in terms of a few summary statistics.

The main cholesterol patterns observed above

for the entire sample of U.S. youths aged 12-17

. . .——.

years were similar to those observed for white

and Negro youths separately (table 9 and figures

4 and 5). Mean cholesterol levels in white males

were highest for 12-year-olds (180.2 mg/100 ml)

and decreased with age to a low of 166.7

mg/100 ml for 16-year-olds. For white females,

there was little change with age in mean cholesterol levels except for a sharp increase from

177.7 mg/100 ml for 16-year-olds to 184.2

mg/ 100 ml for 17-year-olds. Mean cholesterol

280

240

120

Male

01

12 13 14 15 16 17

AGE IN YEARS

280

t

Female

u! I

0

12 13 14 15 16 17

AGE IN YEARS

Figure 2. Selected estim6ted percentiles of the cholesterol distribution in youths aged 12-17 years, by age and sex: United .St8teS,

1966-70.

4
190

t Male

_ Northeast

J

---Midwest

___ Seuth

---- West

o~12 13 14 15 16 17

AGE IN YEARS

190

t

Female

160--

.. ~,--:>...<,’

%... ..% “.. /’ .7-/

------ ,x. /“ ‘\\

~. #

.“,’ .. ... ..~

170

‘6:d ’12. 13 14 15 16 17

AGE IN YEARS

Figure 3. Mean cholesterol Ievelsof maleand femeleyouths 12-17years ofage, byageand geographic region: United States, l9~7O.

&

Males

200

Females

200 I-

----------------------- ---------------- -- ---e --------

w

d

--------------- -------

d

~z

&- +A

gs

5!8

~ ~ 100-

:: 100 -

Zz

00

$Z

$

z

White _ White

Negro

2

---- —--- Negro

0

I , , 0

t t 1 ,

12 13 14 15 16 17 12 13 14 15 16 17

AGE IN YEARS AGE IN YEARS

Figure 4. Mean cholesterol levels of male and female youths 12-17 years of age, by age and race: United States, 1966-70.

levels in Negro males were highest for 12-yearolds (187.2 mg/100 ml) and decreased with age

to a low of 173.3 mg/100 ml for 16-year-olds.

At every age except 12 years, both white and

Negro female youths had higher mean cholesterol levels than their male counterparts. At age

12, however, the mean levels were higher for

boys of both races than for girls.

In addition, Negro male and female youths

had higher mean serum cholesterol levels than

their white counterparts at every age except 12,

with interracial differences being greater for

males than for females. The average differences

between the mean cholesterol levels of white

and Negro youths over the six age groups was

7.8 mg/100 ml for males and 2.7 mg/100 ml for

females. In general, interracial differences were

greater at the upper end of the cholesterol

distribution than at the lower end (figure 5).

Annual Family Income, Education

of Parent, Age, and Sex

Mean cholesterol levels are given by annual

family income, age, and sex in table 10 and

education of parent, age, and sex in table 11. No
240

t

Males

I

------- ..z~

3

~ 200

g

------ 3 ----------------- ----- SO*

~

~ 160

z

~

----------------------- ---- UJ

2

0

a 120

I

_ White ----Negro

0’ 1 , 1 ,

12 13 14 15 16 17

AGE IN YEARS

[– y

Females

24o

------ goth

-.0-... ---------

~--- -.

----

-------

=

z 200

~ ..--% --- z

.-- ----------- ------ 5oth

~

P

‘----

~ 160

K

w

~

t-

/ Ioth

- ---------- --- - -------

*

w.

----------

I

— White

---- Negro

01 t 1 , 1 1

12 13 14 15 16 17

AGE iN YEARS

Figure 5. Selected estimated percentiles of the cholesterol distribution in male and female youths 12-17 years of age, by age and race:

United States, 1966-70.

consistent relationship was observed between

cholesterol levels and either annual family

income or education of parent within individual

age groups. However, when all age groups were

combined, the mean cholesterol levels averaged

3.4 mg/ 100 ml higher for male youths and 6.8

mg/ 100 ml higher for female youths whose

families had annual incomes of $10,000 or more

than for those youths whose families had incomes of less than $3,000 per year (table 12).

Similar patterns were observed in the relationship between mean cholesterol levels and parental education.

Mean cholesterol levels are shown separately

for white and Negro youths by annual family

income, age, and sex in table 13 and by education of parent, age, and sex in table 14. When all

age groups were combined (table 12), a general

increase in mean cholesterol with increase in

family income was observed for both white and

Negro youths. Likewise, both white and Negro

youths whose parents had 12 years or more of

education generally showed higher mean cholesterol levels than those whose parents had less

than 12 years of education. When contrasting

the socioeconomic extremes, youths of aIl ages

in the highest socioeconomic groups had higher

cholesterol levels than those in the lowest socioeconomic groups.

DISCUSSION

The role of cholesterol as a risk factor in

increased morbidity and mortaIity from cardiovascular disease has been an issue for decades.

Evidence of its centrzd role in the development

of atherosclerosis comes from three sources.

First, certain disease states in man involving

abnormally high serum cholesterol levels are also

associated with accelerated atherosclerosis. Examples of such disease states are hyperlipoproteinemias (Fredrickson Types II, III, and IV) and

poorly controlled diabetes mellitus, both entities

known to be associated with accelerated atherosclerosis.17 Second, “epidemics” of atherosclerosis currently occurring in the United States

and the Scandinavian countries are unknown in

populations where serum cholesterol levels are

low. Although high levels of serum cholesterol in

epidemiological studies are not always associated

with high rates of atherosclerosis, low levels of

serum cholesterol always appear to be associated

with low levels of atherosclerosis. 18 Third, it h=

been known for many years from animal experiments and human autopsy data that esterified

cholesterol is the principal lipid constituent of

the fatty streak and the fibrous plaque.19 ~zO

Despite these facts, there has been considerable debate over the role cholesterol plays in the

6
pathogenesis of atherosclerosis. The debate has

ranged from advocating cholesterol as the major

and primary determinant in the development of

atherosclerosis to the other extreme of describing its role as only a secondary or facilitating

one. Current opinion seems to implicate elevated

levels of serum lipids as one of a number of

major risk factors such as hypertension, smoking, and diabetes mellitus.z 1 Nongenetic elevation of serum cholesterol occurring in one of the

technologically developed countries is usually

associated with a high-calorie diet characterized

by significant amounts of cholesterol and animal

fat. To complicate the issue even more, recent

evidence implicates hypertriglyceridemia as an

independent risk factor in the development of

ischemic heart disease.z z Therefore, it is possible that serum cholesterol may not be the only

lipid in the serum to signify higher risk for heart

disease in middle-aged adults.

It is important to note, however, that serum

cholesterol may continue to be a useful index

determination for high &k for cardiovascular

disease for three reasons. First, the exact role of

hypertriglyceridemia as a predictor of risk in

cardiovascular disease is not as solidly based as

that of hypercholesterolemia. Second, cholesterol levels are not as affected by the immediate

fed or fasted state as are the serum triglycerides.

Third, serum triglycerides may reflect the current nutritional status in days or weeks, whereas

serum cholesterol is more likely to be representative of lipid metabolism over a period of

months. Therefore the’ accurate measurement

and interpretation of serum triglyceride levels

requires immediate dietary knowledge which is

not as important when using serum cholesterol

for survey or screening purposes.

Much of our epidemiologic knowledge about

the clinical implications of elevated serum cholesterol and triglycerides in adult morbidity and

mortality is relatively recent, and it is based

essentially on adult data such as the classical

longitudinal study conducted in Framingham,

Massachusetts.z1 There are no analogous longitudinal data gathered directly from adolescents

that link elevated cholesterol in adolescence

(whether it be of genetic and dietary origin or

secondary to other diseases such as hypothyroidism, diabetes mellitus, and the nephrotic syndrome) with future morbidity and mortality.

There ‘ is, however, evident; from autop;y

studies that fatty streaking of the abdominal

aorta, a precurser to atherosclerosis, can be well

established during adolescence and may accelerate more rapidly at adolescence than at any

other time,z 3 and that accelerated coronary

disease can be found (though uncommonly) in

men in their twenties and with increasing frequency in men in their thirties.z4 Thus, if

elevated serum cholesterol plays a significant

causal role in adult atherosclerotic disease, and if

it could be demonstrated that purposefully

lowering these levels by dietary and/or other

means significantly lowers the risk, then the

adolescent period would not be too early to

attempt its detection and control.

Age and Sex

The relationship between serum cholesterol

levels and age is different in adolescent males

and females in the United States. Mean cholesterol levels in males declined from a high of

181.3 mg/100 ml in 12-year-olds to 167.7

mg/ 100 ml in 16-year-olds, with the biggest

differences between adjacent age groups occurring between ages 12 and 13 (6.6 mg/100 ml)

and between ages ,13 and 14 (4.8 mg/100 ml).

From age 14 on, there appeared to be little if

any change in mean cholesterol levels among

males. On the other hand, there was little if any

difference in mean cholesterol levels of females

aged 12-16 years, with mean levels ranging from

175 to 178 mg/100 ml. At age 17, however,

there was a sudden increase of 6.4 mg/ 100 ml in

mean levels over that observed from 16-year-old

females–178.l mg/100 ml vs. 184.5, respectively. Except at age 12, female youths in each

age group had higher mean cholesterol levels

than their male counterparts (table 3).

Among adolescent males and females of all

ages, the distribution of cholesterol levels was

not symmetric but skewed to the right (positive

skewness). In male youths 12-17 years of age

and in female youths 12-16 years of age, the

mean of the cholesterol distribution was 1.5 to

3.0 mg/100 ml higher than

17-year-old females, however,

the median. In

the distribution

7
was much more skewed with the mean being 5:3

mg/ 100 ml greater than the median.

These estimates for U.S. youths with respect

to age and sex can be compared with findings of

other studies of cholesterol in adolescents. A

study conducted in Tecumseh, Mich., k 1959-60

involved an extensive medical examination of 88

percent of the town’s entire population (approximately 9,800 persons at that time). Included in

this examination were serum cholesterol deterrninations.z5 The Tecumseh study represents

more than just a collection of persons since its

results can be extrapolated to a specified population (i.e., that of Tecumseh, Mich., 1959-60).

Unfortunately, because Tecumseh findings on

cholesterol were presented for the combined age

groups 10-14 years and 15-19 years, a more

detailed comparison with HES results is not

possible. However, in both of the Tecumseh age

groups, females had higher mean cholesterol

levels than males, a finding consistent with that

of the HES.Zs

In other studies such as the following, it was

found that adolescent girls have higher cholesterol levels than adolescent males:

●

●

●

On

Among 1,200 healthy males and females of

all ages in New York City, females aged

13-17 years had higher mean cholesterol

levels than males of comparable ages.zG

In a longitudinal study of 152 girls and 169

boys in Utah, girls were found to have

higher mean cholesterol levels than their

male counterparts.z T

Analysis by single years of age of data for

885 volunteer and nonvolunteer male and

female students aged 12-18 attending

public and parochial schools in Burlington,

Vt., revealed that 12-year-old males had

higher mean cholesterol levels than 12-yearold females; 13-year-old males and females

had approximately equal cholesterol levels;

but beginning with age 14, however,

females had higher levels than their male

counterparts.z 8

the other hand, a study conducted in rural

Georgia showed no consistent differences in

8

mean cholesterol levels between male and female

adolescents.z g

The decrease with age in mean cholesterol

levels found in HES adolescent males was observed through age 16 both in the Burlington,

Vt., studyz8 and in the survey of 613 school

boys 11-18 years of age conducted in Sydney,

AustraliansO Different patterns were observed,

however, among adolescent males in two rural

surveys: the one already mentioned above conducted in Geor~iaz g and another one conducted

in Busselton, Australians1 The sharp increase in

cholesterol levels from age 16 to age 17 observed

in U.S. females was also apparent among females

in the Burlington, Vt., survey.zs The validity of

the age-sex patterns found in Cycle III is further

strengthened by the fact that when mean cholesterol levels are plotted by age and sex for white

and Negro youths separately, the curves for

white youths are parallel to those for Negro

youths (figure 4), even though the curves for the

latter group are based on relatively small sample

sizes in each age group.

The estimates of cholesterol levels for U.S.

adolescents obtained from Cycle III of the

Health Examination Survey can be compared by

extrapolation with those that have been reported for adults in HES Cycle 1.sz Table 13

shows mean levels of cholesterol obtained for

adults in Cycle I by age and sex along with

standard deviations of the population distribution, and figure 6 shows these mean cholesterol

levels in conjunction with those found for U.S.

adolescents in Cycle III. In comparing the mean

levels of 17-year-old males (mean age 17.5

years), the oldest age group of Cycle 111,with

those of 18- to 24-year-old males (mean age 21.5

years), the youngest age group of Cycle I, we

note an average increase of 1.82 mg/ 100 ml per

year (figure 6). Similar examination of Cycle I

data for males in other age groups shows an

average yearly increase of 3.27 mg/ 100 ml from

age 21.5 to age 30, 2.09 mg/100 ml from age 30

to age 40, and much smaller increases thereafter.

Thus, the mean cholesterol level obtained for

17-year-old males in HES Cycle III is consistent

with the Cycle I finding that cholesterol levels

rise sharply with age in young men. Similar

analysis of the mean cholesterol level in 17-yearold females (mean age 17.5 years) with those of
— Male

---- Female

160 -

150-

Cycle III ~ Cycle I u

o

1 , I 1

10 20 30 40 50 60 70 80

AGE IN YEARS

18- to 24-year-old Cycle I women (mean age

21.5) shows practically no difference in mean

cholesterol levels between the two age groups

(figure 6). Thus, the sharp increase in mean

cholesterol level observed in these HES data

between 16- and 17-year-old femalesd is not

followed by continued increase during the age

interval 18-24 years, and the gradual rise in

cholesterol level among women apparently does

not begin until the mid or late twenties, whereas

in males the rise is not only steeper but it begins

earlier.

‘The 80.2 percent response rate in 17-year-old females was

the lowest obtained in the survey (see appendix); and this may

account for some of the unexplainable findings observed in this

age-sex group.

Figure 6. Meen cholesterol levels for adults in HES Cycle I (1960-62) and youths in HES Cycle III (1966-70): United States.

Not only are the mean cholesterol levels

higher in U.S. adults than in U.S. adolescents

but also the distributions have greater variability

in adults than in youths 12-17 years of age

(tables 3 and 15). The coefficient of variation of

the cholesterol distribution averages about 17

percent in adolescents, whereas it averages about

22 percent in adults.

All other major studies of cholesterol in

adults have also obtained mean levels that were

considerably higher than those obtained in this

Cycle III survey of male and female youths

12-17 years of age.zl *Zs~ze

Race

One of the most striking findings of this

survey was that both male and female Negro

9
youths showed higher cholesterol levels than

white youths of comparable age and sex. These

differences between white and Negro youths

were greater in males than in females and were

greatest at the upper percentiles of the distribution. The average difference over all six age

groups in mean cholesterol levels between white

and Negro youths was 7.8 mg/ 100 ml in males

and 2.7 mg/100 ml in females. Racial differences

also occurred in all socioeconomic classes as

measured by family income or education of

parent. Two other studies of cholesterol in U.S.

adolescents have reported findings of little or no

interracial differences in mean cholesterol.zg’ aa

However, the fact that one of these studies was

in a very rural areazg and the other was based

on a very small sample from both groups33

makes it difficult to relate the findings to HES

results.

In the HES survey of U.S. adults (Cycle I),

white males and females had consistently higher

mean cholesterol levels than Negro adults of

comparable age and sex. Other studies have

shown racial differences in cholesterol levels. A

study of cholesterol levels in Southwestern

American Indians and white controls showed

lower cholesterol levels among the Indians.34

Outside of the United States, a survey of children and adolescents in South Africa among

white, Bantu, and Cape Coloured populations

showed findings of higher cholesterol levels in

the white children than in either the Bantu or

Cape Coloured children.35

Annual Family Income

It appears from these data on U.S. adolescents

that a positive relationship exists between mean

cholesterol levels and family income although

the relationship is not consistent for all age-sex

groups. However, when all age groups are combined (table 12), there is a consistent increase in

the mean cholesterol levels of both male and

female youths with increase in family income.

The group of males whose families had annual

incomes of less than $3,000 had a mean cholesterol level of 170.6 mg/ 100 ml, whereas males

whose families had annual incomes of $10,000

or more had a mean level of 174.0 mg/100 ml,

reflecting an increase of 3.4 mg/ 100 ml from the

lowest to the highest of family income. The

comparable increase for females, was 6.8

mg/100 ml, from a low of 172.7 mg/100 ml

among those whose families had annual incomes

of less than $3,000 to a high of 179.5 among

those whose families had incomes of $10,000 or

more.

Since 34.8 percent of the Negro youths as

opposed to only 9.3 percent of the white youths

come from families with annual incomes of less

than $3,000, the income group showing the

lowest cholesterol levels, and since Negro youths

have higher mean cholesterol levels than white

youths at all income levels (table 12), the relationships observed above between annual family

income and mean cholesterol levels in the total

population are greatIy influenced by the disproportionate number of Negro youths in the

lower income groups. These two factors working

in opposite directions obscured and dampened

the effective relationship between family income

and cholesterol levels. Thus, we see that the’

relationship between mean cholesterol and

annual family income is stronger when examined

separately in the white population than when

examined in the total population (table 12). In

white males the gradient in mean cholesterol

level from the lowest to the highest income

group was 7.9 mg/100 ml, whereas in the total

male population the gradient was only 3.4

mg/ 100 ml. The comparable gradients in females

were 7.4 mg/ 100 ml for white females as

opposed to 6.8 mg/100 ml for the total female

population.

Other Studies

Several studies involving children and adolescents have investigated the relative influences of

heredity and environment as determinants of

cholesterol levels. The Busselton survey,~ 1 the

Tecumseh study,z 5 and a survey of residents of

two Greek villagessG indicated considerable

evidence of familial aggregation of cholesterol

levels. In each of these studies, correlational

methods were used to demonstrate parent-cKlld

and sibling-sibling relationships. The general conclusion of these studies was that the findings

10
were more compatible with a quantitive multi- in female pairs but not in male pairs.37 For this

factorial mechanism of inheritance than with a particular group of twins, it was concluded that

single-gene genetic model. genetic determinants of cholesterol levels were

On the other hand, a study of 108 like-sex generally of a smaller order of magnitude than

twin pairs showed that variation in cholesterol environmental determinants. Thus, it appears

level between monozygotic twins was signifi- that both heredity and environment influence

cantly smaller than that between dizygotic twins cholesterol levels.

,4

000

REFERENCES

1National Center for Health Statistics: Origin, program, and operation of the U.S. National Health Survey.

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

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

2Nation~ Center for He~th Statistics: pl~ ~d

initial program of the Health Examination Survey. Vital

and Health Statistics. PHS Pub. No. 1000-Series l-No. 4.

Public Health Service. Washington. U.S. Government

Printing Office, July 1965.

3National Center for Health Statistics: Plan, operation, and response results of a program of children’s

examinations. Vital and Health Statistics. PHS Pub. No.

1000-Series l-No. 5. Public Health Service. Washington.

U.S. Government Printing Office, Oct. 1967.

4Nation~ Center for Health Statistics: Plan ~d

operation of a Health Examination Survey of U.S.

youths 12-17 years of age. Vital and Health Statistics.

PHS Pub. No. 1000-Senes l-No. 8. Public Health Service. Washington. U.S. Government Printing Office,

Sept. 1969.

5National Center for Health Statistics: Height and

weight of youths 12-17 years, United States. Vital and

Health Statistics, Series 1l-No, 124. DHEW Pub. No.

(HSM) 73-1606. Health Services and Mental Health

Administration. Washington. U.S. Government Printing

Office, Jan. 1973.

6National Center for Health Statistics: Body weight,

stature, and sitting height: White and Negro youths

12-17 years, United States. Vital and Health Statistics.

Series 1l-No. 126. DHEW Pub. No. (HRA) 74-1608.

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

7Nation~ Center for Heal~ Statistics: Skinfold

thickness of youths 12-17 years, United States. Vital and

Health Statistics. Series 1l-No. 132. DHEW Pub. No.

(HRA) 74-1614. Health Resources Administration.

Washington. U.S. Government Printing Office, 1974.

8Nation~ Center for Health Statistics: Hematocnt

values of youths 12-17 years, United States. Vital and

Health Statistics. Series 1 l-No. 146. DHEW Pub. No.

(HRA) 75-1628. Health Resources Administration.

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

1974. ,

9National Center for Health Statistics: Serum uric

acid values of youths 12-17 years, United States. Vital

and Health Statz”stz”cs. Series 1l-No. 152. DHEW Pub.

No. (HRA) 76-1634. Health Resources Administration.

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

1975.

10Herskowits, M.J.: The Amen-can Negro; a Study in

Racial Crossing. New York. Alfred A. Knopf, 1928.

11GIxs, B., ~d Li, C.C.: The dynamics of raci?d

intermixture-an analysis based on the American Negro.

Am.J.Hum. Genet. 5(1):1-20, Mar. 1953.

12 Roberts, D. F.: The dynamics of racial intermixture

in the American Negro: Some anthropological considerations. Am. J.Hum. Genet. 7(4):36 1-367, Dec. 1955.

13 Roberts, D. F., and Hiorns, R.W.: The dynamics of

racial intermixture. Am.J.Hum. Genet. 14(3) :261-277,

Sept. 1962.

14 Reed, T. E.: Caucasian genes in American Negroes.

Science 165(3895): 762-768, Aug. 22, 1969.

15 Eavenson, E., Grier, O.T., Cisson, J.G. and Witter,

R. F.: A semiautomated procedure for the determination

of serum cholesterol using the Abell-Kendall method. J.

Am. Oil Chem. Sot. 43(12):652-656, 1966.

16Henry, Richard J.: Clinical Chemistry, Principles

and Technics. New York. Hoeber Medical Division,

Harper & Row, 1965.

11
17 Fredrickson, D.S., and Levy, R.L: “Fa&lial hyperIipoproteinemia,” in J.B. Stanbury, J.B. Wyngaarden,

and D.S. Fredrickson, eds., The Metabolic Basis of

Inherited Disease, 3rd ed. New York. McGraw-Hill Book

Co., 1972. pp. 545-614.

18Sherwin, R.: The epidemiology of atherosclerosis

and coronary heart disease. Postgrad. Med. 56(6):81-87,

1974.

19 Smith, E.B.: lntimd and medial lipids in hum~

aortas. Lancet, Vol. 1, Part II: 799-803, Apr.-June,

1960.

Zo%nith, E.B.: The influence of age and atherosclerosis on the chemistry of aortic intima. Part I. The

Lipids. J.Atheroscler. Res. 5:224-240, 1965.

21 K-el, W-B+, ad Gordon, “rQ,eds.: Me~s at each

exam ination and inter-examination variations of

specified characteristics. Section 29, The Framingham

Study, exam l-exam. 10. DHEW Pub. No. (NIH) 74-478,

Dec. 1973.

22 Cdson, L. A., and B6ttiger, L. E.: Ischaemic heartdisease in relation to fasting values of plasma triglycerides and cholesterol: Stockholm Prospective Study.

Lancet, Vol. 1, Part II: 865-868, Apr.-June, 1972.

2~HoIman, R. L., et al.: The natural history of atherosclerosis: The early aortic lesions as seen in New Orleans

in the middle of the 20th century. Am. J.Path.

34(2):209-236, Mar. 1958.

24 Enos, W. F., Holmes, R. H., and Beyer, J.: Coronary

disease among United States soldiers killed in action in

Korea. Preliminary Report. J.A.M.A. 152(12):1090-

1093, July 1953.

25Johnson, B.C., Epstein, F.H., and Kjelsberg, M.O.:

Distributions and familial studies of blood pressure and

serum cholesterol levels in a total community—

Tecumseh, Mlchlgan. ]. Chron.Dis. 18, 147-160, Feb.

1965.

26Adlersberg, D.A., Schaefer, L. E., SteinbeW, A. G.,

and Wang, C.-I.: Age, sex, serum lipids, and coronary

atherosclerosis. J. A.M.A. 162(7):619-622, Oct. 1956.

27M~lig~, C.A., Wilcox, E.B., and Galloway, L.S.:

Serum cholesterol and physical characteristics of preadolescents and adolescents. J. Am. Diet. Assoc. 49(4):

309-315, Oct. 1966.

28Clarke, R.P., et al.: Interrelationships between

plasma lipids, physical measurements, and body fatness

of adolescents in Burlington, Vermont. Am.J. Clin.Nutr.

J

23(6 :754-763, June 1970.

2 Hames, C.G., and Greenberg, B.G.: A comparative

study of serum cholesterol levels in school children and

their possible relation to atherogenesis. Am.J. Public

Health 51(3):374-385, Mar. 1961.

SoHickie, J. B<, et al.: Serum cholesterol and serum

triglyceride levels in Australian adolescent males. Med. J.

Aust. 1,825-828, 1974.

31 Godfrey, R. C., Stenhouse, N.S., CuUen, K.J., and

Blackman, V.: Cholesterol and the child: Studies of the

cholesterol levels of Busselton school children and their

parents. Aust.Paediat.J. 8, 72-78, 1972.

32 Nation~ Center for Health Statistics: Serum ch~

Iesterol levels of adults, United States– 1960-1962. Vital

and Health Statistics. PHS Pub. No. 1000-Series 1l-No.

22. Public Health Service. Washington. U.S. Government

Printing Office, Mar. 1967.

38Baker, H., et al.: vitm~s, total cholesterol, and

triglycerides in 642 New York City school children.

Am.J. Clin.Nutr. 20(8):850-857, Aug. 1967.

34 Sievers, M-L.: Semm cholesterol levels in southwestern American Indians. J. Chronic Dis. 21(2): 107-115,

1968.

“35Du Plessis, J. P., Vivier, F.S., and De Lange, D.J.:

The biochemical evaluation of the nutrition status of

urban school children aged 7-15 years: Serum cholesterol and phospholipid levels and serum and urinary

amylase activities. South Afn”can Medical Journal. 41,

1216-22, 1967.

36Mayo, O., Fraser, G. R., and Stamatoyannopoulos,

G.: Genetic influences on serum cholesterol in two

Greek Villages. Hum. HerecL 19, 86-99, 1969.

37 ~d, B.M., et al.: Study of serum lipid levek in

twins. Cardiovasc.Res. 2, 148-156, 1968.

38Nation~ Center for He~th Statistics: s~ple

design and estimation procedures for a national health

examination survey of children. Vital and Health Statistics. Series 2-No. 43. DHEW Pub. No. (HRA) 74-1005.

Health Resources Administration. Washington. U.S. Government Printing Office, Aug. 1971.

89 National Center for Health Statistics: Replication:

An approach to the analysis of data from complex

surveys. Vital and Health Statktics. PHS Pub. No.

1000-Series 2-No. 14. Public Health Service. Washington.

U.S. Government Printing Office, Apr. 1966.

12
LIST OF DETAILED TABLES

,

Table 1, Estimated number of youths aged 12-17 years in the population, by cholesterol group, sex, and age: United

States, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2. Percent distribution of youths aged 12-17 years by cholesterol group, according tosexand age: United States,

1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3, Unweighed and weighted sample sizes, mean cholesterol, standard deviation, standard error, and selected

percentiles,bysexandage: United States,1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4. Mean cholesterol and standard error of the mean for youths aged 12-17 years, by geographic region, sex, and

age: UnitedStates,1966-70. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5. Estimated number of white youths aged 12-17 years in the population by cholesterol group, sex, and age:

UnitedStates, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6. Estimated number of Negro youths aged 12-17 years in the population, by cholesterol group, sex, and age:

UnitedStates, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7. Parcent distribution of white youths aged 12-17 years by cholesterol group, according tosexandaga: United

States, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8. Percent distribution of Negro youths aged 12-17 yaars by cholesterol group, according tosexandaga: Unitad

States, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9. Unweighed and weighted sample sizes, meen cholesterol, standard deviation, standard error, and selectad

percentiles, byrace, sex, andage: United Statas, l966-7O . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10. Weightad sample size, maan cholesterol, andstandard error of themean foryouths agad.12-17 yaars, by age,

sex,andannualfamilyincoma: UnitedStatas,1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

11. Weighted sample size, maan cholesterol, and standard arrorof the mean for youths agad 12-17 years, by aga,

sex,andeducationofparant: UnitadStates,1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

12. Weighted sampla size, mean cholesterol, and standard error of the mean for youths aged 12-17 years, by race,

sex, annual family income, and education of parent: United States, 1966-70 . . . . . . . . . . . . . . . . . .

13. Weighted sample size, mean cholesterol, andstandard error of the mean foryouths agad 12-17 years, by age,

race, sex, andannual family incoma: United States, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . .

14. Waighted sample size, mean cholesterol, and standard error of the mean for youths aged 12-17 years, by age,

race, sax, andeducation ofparent: United States, l966-7O . . . . . . . . . . . . . . . . . . . . . . . . . . .

‘ 15, Mean cholesterol levels andstandard deviations of thepopulation distribution foradults, bysexandage: Unitad

States, 1960-62 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Page

14

14

15

15

16

17

18

19

20

21

21

22

23

24

25

●

13
Tablel. Estimated number ofyouths agd12-17years inthepopulation, bycholesterol group, sex, andage: United States,l966-7O

Male I

Female

Cholesterol group

12

years

13 I

14

years years

15 16 17 12 13 14 15 16 17

years years years years years yaars years years yaars

Estimatad number of youths in population in thousends

1,951 1,900 1,836 1,764 1,970

7

10

17

20

83

131

201

317

299

279

226

141

81

85

30

18

17

3

4

All groups . . . . . . 2,032 2,006 1,946 1,901 1,861 1,769 1,746

Under 100mgpercent . .

100-108 mgpercent . . . .

110-l 19mgpwcent . . . .

120-129 mgpercent . . . .

130-138 mg percent . . . .

140-149 mg ~rcent . . . .

150-159 mg percent . . . .

160-169 mg ~rcent . . . .

170-179 mg percent . . . .

180-189 mg percent . . . .

190-199 mg percent . . . .

200-209 mg p?rcent . . . .

210-219 mg percent . . . .

220-229 mg percent . . . .

230-239 mg percent . . . .

240-249 mg percent . . . .

250-259 mg percant . . . .

260-269 mg psrcent . . . .

270 mg percent and over .

-

8

3

24

65

116

224

251

255

273

217

184

94

120

70

37

29

21

5

10

6

19

47

59

143

228

243

289

227

226

179

102

78

44

27

16

11

3

6

4

16

45

57

171

210

271

290

230

229

130

77

70

23

38

25

3

9

4

6

14

51

71

139

210

252

276

250

229

137

56

64

26

21

13

7

8

7

11

15

32

68

113

194

232

242

221

186

160

92

98

37

22

7

6

7

10

5

3

37

75

104

142

222

227

257

278

184

142

88

60

24

17

8

16

13

6

11

14

19

105

181

222

218

287

238

197

116

101

52

21

23

10

5

22

4

10

31

28

115

204

222

273

214

156

144

115

51

42

52

30

12

33

3

17

43

86

136

179

269

291

287

220

183

113

85

52

25

11

5

27

15

53

97

185

240

245

246

238

170

159

126

78

44

36

6

5

3

18

37

83

173

232

179

280

232

187

87

98

82

61

10

7

9

15

Table 2. Percent distribution of youths aged 12-17 years by cholesterol group, according to sex and age: United States, 1966-70

Male Female

12 13 14 15 16 17 12 13 14 15 16 17

years years years years years years yeers years years yeers years years

Cholesterol group

Percent distribution

All groups . . . . . . . . . 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 I 100.0 100.0 100.0

0.3 0.3

0.2 0.6

2.0 0.8

4.0 1.0

6.5 5.7

7.4 9.8

11.7 12.0

11.9 11.8

13.5 15.5

14.6 12.9

9.7 10.6

7.4 6.3

4.6 5.5

3.1 2.8

1.3 1.1

0.9 1.3

0.4 0.5

0.9 0.3

0.7 1.2

Under 100 mg,percant . .

100-109 mg percant . . . .

110-119 mgpwcent . . . .

120-129 mg percent . . . .

130-139 mg percent . . . .

140-149 mg percant . . . .

150-159 mg percant . . . .

160-169 mg percent . . . .

170-179 mg percent . . . .

180-189 mg pwcent . . . .

190-199 mg pwcant . . . .

200-209 mg percent . . . .

210-219 mg percent . . . .

220-229 mg percent . . . .

230-239 mg percent . . . .

240-249 mg percent . . . .

250-259 mg p?rcent . . . .

260-269 mg percent . . . .

270 mg ~rcent and over .

0.4

0.1

1.2

3.2

5.8

11.2

12.5

12.7

13.6

10.8

9.2

4.7

6.0

3.5

1.9

1.4

1.0

0.2

0.5

0.3

1.0

2.4

3.0

7.3

11.7

12.4

14.8

11.6

11.6

9.2

5.2

4.0

2.2

1.4

0.8

0.6

0.2

0.3

0,2

0.9

2.4

3.0

9.0

11.1

14.3

15.3

12.1

12.1

6.8

4.1

3.7

1.2

1.9

1.3

0.1

0.5

0.2

0.3

0.8

2.8

3.9

7.6

11.4

13.7

15.0

13.6

12.5

7.4

3.1

3.5

1.4

1.2

0.7

0.4

0.4

0.4

0.6

0.8

1.8

3.9

6.4

11.0

13.2

13.7

12.5

11.2

9.1

5.2

6.6

2.1

1.2

0.4

0.3

0.4

0.5

0.3

0.5

0.9

1.0

4.2

6.6

10.2

16.1

15.2

14.2

11.5

7.1

4.1

4.3

1.5

0.9

0.9

0.2

0.2

0.2

0.6

1.8

1.6

6.6

11.7

12.7

15.6

12.2

9.6

8.3

6.6

2.9

2.4

3.0

1.7

0.7

1.9

0.2

0.8

2.1

4.2

6.7

8.8

13.2

14.3

14.1

0.7

2.7

5.0

9.5

12.3

12.6

12.7

12.1

8.7

8.1

6.5

4.0

2.3

1.9

0.3

0.3

0.2

1.0

2.1

4.6

9.7

12.9

10.0

15.6

13.0

10.4

4.9

5,5

4.6

3.4

0.6

0.4

0.5

0.8

10.8

9.0

5.5

4.2

2.5

1.2

0.5

0.3

1.3

NOTE: Percents may not add to 100.0 due to rounding.
Tabla 3. Unweighed and weighted semple sizes, mean cholesterol, stendard deviation, standard error, and salacted percentiles, by sex

and aw: United Statas, 1966-70

Percentile

n N E Sx Sk

5 10 25 50 75 90 95

Sex and age

Male

12 years . . . . . . . . . . . . .

13years . . . . . . . . . . . . .

14 years . . . . . . . . . . . . .

15 years . . . . . . . . . . . . .

16 years . . . . . . . . . . . . .

17 years . . . . . . . . . . . . .

Female

12 yaars . . . . . . . . . . . . .

13 years . . . . . . . . . . . . .

14 yaars . . . . . . . . . . ... .

16 years . . . . . . . . . . . . .

16 years . . . . . . . . . . . . .

17 years . . . . . . . . . . . . .

Cholesterol in mg/100 ml

843

626

618

613

556

489

547

582

586

503

536

469

2,032

2,006

1,951

1,900

1,836

1,764

1,970

1,946

1,901

1,851

1,789

1,746

181.3

174.7

169.9

188.5

16,7.7

170.8

178.0

177.7

175.3

176.8

178.1

184.5

29.85

31.19

30.20

29.84

28.57

30.36

27.87

29.46

31.86

30.26

30.01

34.16

1.40

1.17

1.56

1.40

1.76

1.70

0.98

1.74

1.59

1.59

1.86

1.31

137.4

128.3

125.1

126.3

123.3

125.3

135.8

133.4

125.8

133.8

136.1

141.0

146.4

138.4

134.7

135.4

134.7

133.7

143.8

141.5

137.1

141.5

143.3

148.4

160.9

152.8

149.4

148.5

149.1

150.4

161.0

156.0

155.1

156.1

156.3

161.8

?79.5

171.8

167.8

165.5

165.8

169.1

176.2

174.7

173.8

175.3

175.7

179.2

199.3

193.2

188.8

185.4

184.0

189.8

194.1

198.5

192.5

194.3

196.2

201.8

219.4

217.3

207.7

207.6

201.6

211.6

214.2

218.8

212.8

213.4

221.0

226.6

232.5

230.5

221.4

220.5

217.6

220.4

225.6

229.6

226.1

225.6

231.7

24a5

NOTE: n=sample size; N= estimated number of youths inthou~nds; ~=mean; sx=mandard deviation; s~=standard errorof

the mean.

Table 4. Meen cholesterol and standard error of themean for youths aged 12-17 years, bygeographic region, sex, and age: United

States, 1966-70

9

Sex and age

Male

12 years . . . . . . . . . . . . . . . . . . . . . . . . .

13 yaars . . . . . . . . . . . . . . . . . . . . . . . . .

14 years . . . . . . . . . . . . . . . . . . . . . . . . .

15 years . ...,.,. . . . . . . . . . . . . . . . . .

16 yaars . . . . . . . . ,., . . . . . . . . . . . . . .

17 years . . . . . . . . . . . . . . . . . . . . . . . . .

Female

12 years . . . . . . . . . . . . . . . . . . . . . . . . .

13 years . . . . . . . . . . . . . . . . . . . . . . . . .

14 years . . . . . , . , . . . . . . . . . . . . . . . . .

15 yaars . . . . . . . . . . . . . . . . . . . . . . . . .

16 years . . . . . . . . . . . . . . . . . . . . . . . . .

17 years . . . . . . . . . . . . . . . . . . . . . . . . .

Geographic region

Total

North- MidSouth Wast

east west

Mean cholesterol in mg/100 ml

Wast

Standard error

181.3

174.7

169.9

168.5

167.7

170.8

178.0

177.7

175.3

176.8

178.1

184.5

185’.2

175.2

172.6

169.9

172,6

175.6

176.5

183.9

179.5

180.0

184.7

184.6

181.1

173.8

174.3

169.2

165,3

165.4

180.8

177.2

170.9

177.6

174.5

184.4

182.4

175.3

166.3

168.0

163.9

167.6

175.7

173.1

176.2

179.6

179.3

185.2

177.0

174.5

165.9

166.9

170.4

175.3

177.9

177.1

175.6

170.7

175.9

184.0

1.40

1.17

1.56

1.40

1.76

1.70

0.98

1.74

1.59

1.59

1.86

1.31

2.36

2.69

3.79

2.25

2.25

3,42

2.02

2.49

3.01

3.26

2.84

2.58

1.90

1.98

2.92

3.50

2.76

1.91

2.21

3.69

3.02

2.48

3.65

1.87

3.25

3.10

2.15

3.06

4.84

3.28

3.84

3.67

3.09

3.32

3.97

3.64

4.12

1.58

2.16

3.76

3.22

2.61

1.52

3.87

3.03

4.13

3.57

3.50

16
Table 5. Estimated number of whita youths aged 12-17 yaarsin the population by cholesterol group, sex, andaga: United States,

Cholesterol group

Al I groups . . . . . .

Under 100mg percent . .

100-109 mgpercent . . . .

110-l 19mgpercant . . . .

120-129 mgpxcent . . . .

130.138 mgpercent ,.. .

140-149 mg percant . . . .

150-159 mg percent . . . .

160-169 mg percent . . . .

170-179 mg percent . . . .

180-189 mg ~rcent . . . .

190-199 mg percent . . . .

200-209 mg percent . . . .

210-219 mg percant. . . . .

220-229 mg percent . . . .

230-239 mg pwxmt . . . .

240-249 mg percent . . . .

250-259 mg percent . . . .

260-269 mg percent . . . .

270 mg percent and over

1966-70

Male I

Female

12

yaars

1,747

3

17

35

81

118

161

212

266

253

193

160

92

63

42

21

8

3

19

13

years

1,729

8

20

55

102

211

201

230

241

205

160

69

104

39

34

22

11

5

10

14

yaars

15 I

16

years years

17 I

12

years years

13 14 15 16 17

years years years years years

Estimated number of youths in population in thousands

1,686

6

17

43

56

125

208

216

258

190

166

160

88

69

28

27

13

8

3

3

1,646

4

14

45

49

157

195

257

237

178

200

107

58

54

23

31

25

3

9

3

1,594

6

14

37

64

132

201

233

225

218

186

110

47

57

18

18

9

7

8

7

1,528

11

15

32

54

101

168

195

232

190

178

133

73

74

32

19

7

6

4

3

1,685

7

10

14

20

70

102

176

270

246

242

206

123

68

68

28

12

14

3

4

1,667

12

42

92

162

212

214

223

213

131

129

98

62

35

35

3

3

1,633

2

3

27

66

98

118

204

180

221

245

160

121

73

51

21

12

3

13

13

1,594

~

6

11

8

19

85

167

199

177

251

203

180

90

93

40

14

19

10

5

19

1,542

18

23

78

159

197

157

250

202

148

67

91

68

51

6

5

7

15

1,502

4

8

28

23

88

173

187

263

199

129

132

90

42

28

36

27

12

30

16
Tabla 6. Estimated number of Negro youths aged 12-17 years in the population by cholesterol group, sex, and age: United States,

Cholesterol group

All groups . . . . . . . . . .

Under 100mg percent . . . . . .

100-109 mg percent . . . . . . .

110.119 mg percent ,., ,.. .

120-129 mg percent . . . . . . .

130-138 mg percent . . . . . . .

140-149 mg percent . . . . . . .

150-159 mg percent . . . . . . .

160-169 mg percent . . . . . . .

170-179 mg percent . . . . . . .

180-189 mg percent . . . . . . .

190-199 mg percent . . . . . . .

200-209 mg percent . . . . . . .

210-219 mg percent . . . . . . .

220-229 mg percent . . . . . . .

230-238 mg percent . . . . . . .

240-249 mg parcent . . . . . . .

250-259 mg percent . . . . . . .

260-269 mg percent . . . . . . .

270 mg parcant and over . . . .

1966-70

Male Female

12 13 14 15 16 17 12 13 14 15 16 17

years years years years years years years years years years years years

Estimated number of youths in population in thousands

280

~

8

5

18

18

57

24

34

27

19

21

22

10

3

3

3

8

262

3

3

10

14

13

38

24

29

12

24

25

16

31

3

7

10

256

2

4

3

18

20

27

31

34

52

19

14

8

15

3

3

2

241 231

2 -

14

9 7

14 4

16 9

14 19

50 50

52 33

23 39

23 27

19 10

13 8

8

5 -

3

2 -

225

14

12

26

37

10

31

17

24

19

24

3

2

6

-

272

3

13

29

25

47

53

37

18

12

13

12

2

2

3

275

2

7

5

23

28

32

23

23

39

30

27

16

9

3

3

5

266

3

10

10

5

24

18

47

36

30

23

21

15

8

3

5

5

3

I

235 243

6 -

14

21 5

12 14

18 35

31 22

37 30

37 27

17 37

23 19

8 7

12 13

7 10

4 5

2

2

3 -

237

2

3

6

26

31

31

10

15

36

12

25

9

14

10

3

2

17
Table 7. Percent distribution Of white youths agad 12-17 years by cholesterol group, according to sex and age: United States, 1966-70

Cholesterol group

All groups . . . . . .

Under 100 mg percent . .

100-109 mg percent . . . .

110-l 19mgpercent . . . .

120-129 mg percent . . . .

130-139 mg percent . . . .

140-149 mg percent . . . .

150-159 mg percent . . . .

160-169 mg percent . . . .

170-179 mg percent . . . .

180-189 mg percent . . . .

190-199 mg percent . . . .

200-209 mg percant . . . .

210-219 mg percent . . . .

220-229 mg parcant . . . .

230-239 mg percent . . . .

240-249 mg percent . . . .

250-259 mg percent . . . .

260-269 mg percent . . . .

270 mg percent and over .

Male Female

12 13 14 15 16 17 12 13 14 15 16 17

years years years years years years years years years years years years

Percent distribution

100.0

0.2

1.0

2.0

4.6

6.8

9.2

12.2

15.3

14.5

11.1

9.1

5.3

3.6

2.4

1.2

0.4

0.1

1.1

100.0

0.5

1.2

3.2

5.9

12.2

11.6

13.3

13.9

11.9

9.2

4.0

6.0

2.2

2.0

1.3

0.6

0.3

0.6

100.0

0.3

1.0

2.5

3.3

7.4

12.3

12.8

15.3

11.3

10.0

9.5

5.2

4.1

1.7

1.6

0.8

0.5

0.2

0.2

100.0

0.3

0.9

2.7

3.0

9.5

11.8

15.6

14.4

10.8

12.2

6.5

3.5

3.3

1.4

1.9

1.5

0.2

0.5

0.2

100.0

0.4

0.9

2.3

4.0

8.3

12.6

14.6

14.1

13.7

11.7

6.9

2.9

3.6

1.1

1.1

0.6

0.4

0.5

0.4

100.0

0.7

1.0

2.1

3.6

6.6

11.0

12.8

15.2

12.4

11.7

8.7

4.8

4.9

2.1

1.2

0.5

0.4

0.3

0.2

100.0

0.4

0.6

0.8

1.2

4.2

6.1

10.4

16.0

14.6

14.4

12.3

7.3

4.1

4.0

1.7

0.7

0.6

0.2

0.2

100.0

0.7

2.5

5.5

9.7

12.7

12.8

13.4

12.8

7.9

7.7

5.9

3.7

2.1

2.1

0.2

0.2

100.0

0.1

0.2

1.7

4.0

6.0

7.2

12.5

11.0

13.5

15.0

9.8

7,4

4.5

3.1

1.3

0.7

0.2

0.8

0,8

100.0

0.4

0.7

0.5

1.2

5.3

10.4

12.5

11.1

15.7

12.7

11.3

5.6

5.8

2.5

0.9

1,2

0.6

0.3

1.2

100.0

1.2

1.5

5.0

10.3

12.8

10.2

16.2

13.1

9.6

4.4

5.9

4.4

3.3

0.4

0.3

0.5

1.0

100.0

0,3

0,s

1.9

1,5

5,9

11,5

12.4

17.5

13.2

8.6

8.8

6.0

2.8

1.9

2.6

1.8

0,8

2.0

NOTE: Percents may not add to 100.0 due to rounding.

18
Table 8. Percent distribution of Neriro youths aged 12-17 years by cholesterol group, according to sex and age: Unitad States, 1966-70

Cholesterol group

All groups . . . . . .

Under 100 mg percent . .

100-109 mg percent . . . .

110-l 19mgpercent ., . .

120-129 mg percent . . . .

130-139 mg percent . . . .

140-149 mg percent . . . .

150-159 mg percent . . . .

160-169 mg percent . . . .

170.179 mg percent . . . .

180-189 mg percent . . . .

190-199 mg percent . . . .

200-209 mg percent . . . .

210-219 mg percent . . . .

220-229 mg percent . . . .

230-239 mg percent . . . .

240.249 mg percent . . . .

250.259 mg percent . . . .

260-269 mg percent . . . .

270 mg percent and over .

Male Female

12 13 14 15 16 17 12 13 14 15 16 17

years years years years years years years yaars years years yaars years

Percent distribution

100.0

2.8

1.8

6.6

6.5

20.2

8.7

12.2

9.5

6.6

7.4

7.9

3.6

1.2

1.1

1.0

2.8

100.0

1.0

1.3

3.7

5.2

4.8

14.7

9.2

11.0

4.6

9.3

9.4

6.2

12.0

1.2

2.6

3.8

100.0

0.9

1.5

1.3

7.0

7.7

10.6

12.1

13.3

20.4

7.4

5.4

3.2

5.9

1.1

1.1

0.9

100.0

0.9

3.6

5.8

6.5

5.6

20.7

21.5

9.6

9.7

8.0

5.2

2.1

0.8

100.0

6.0

3.1

1.7

3.9

8.3

21.8

14.1

16.8

11.5

4.2

3.4

3.7

1.4

100.0

6.2

5.5

11.3

16.4

4.4

13.7

7.7

10.7

8.3

10.5

1.3

1.1

2.8

I00.0

1.1

4.9

10.5

9.2

17.4

19.7

13.6

6.8

4.4

4.8

4.6

0.9

0.9

1.3

100.0

0.8

2.6

2.0

8.4

10.3

11.4

8.4

8.3

14.0

10.9

9.9

5.8

3.2

0.9

1.1

1.8

100.0

1.1

3.6

3.7

2.0

8.9

6.7

17.6

13.5

11.3

8.8

7.9

5.7

3.1

1.0

1.9

2.0

1.1

100.0

2.6

8.7

4.9

7.7

13.3

15.7

15.7

7.1

9.7

3.6

5.1

2.9

1.7

1.3

100.0

5.9

2.1

5.7

14.4

9.0

12.5

11.2

15.2

8.0

2.8

5.4

4.2

1.9

0.7

1.0

100.0

1.0

1.1

2.3

11.2

13.3

13.0

4.2

6.3

15.4

5.0

10.6

4.0

5.9

4.4

1.3

1.0

NOTE: Percents may not add to 100.0 due to rounding.

19
Table 9. Unweighed and weighted sample sizes, mean cholesterol, standard deviation, standard error, and salected percantilas, by race,

Race, sax, and age

Whita male

12 years . . . . . . . . . . . . .

13 years . . . . . . . . . . . . .

14 years . . . . . . . . . . . . .

15 years . . . . . . . . . . . . .

16years . . . . . . . . . . . . .

17 years . . . . . . . . . . . . .

White famale

12 years . . . . . . . . . . . . .

13years . . . . . . . . . . . . .

14 years . . . . . . . . . . . . .

15years . . . . . . . . . . . . .

16yaars . . . . . . . . . . . . .

17 years . . . . . . . . . . . . .

Nemo male

12years . . . . . . . . . . . . .

13years . . . . . . . . . . . . .

14years . . . . . . . . . . . . .

15years . . . . . . . . . . . . .

16years . . . . . . . . . . . . .

17years . . . . . . . . . . . . .

Negro female

12years . . . . . . . . . . . . .

13years . . . . . . . . . . . . .

14years . . . . . . . . . . . . .

15years . . . . . . . . . . . . .

16years . . . . . . . . . . . . .

17years . . . . . . . . . . . . .

sex, andaga: United States, 1966-70

Percentile

n N z

5X SF

5 10 25 50 75 90 95

540

542

527

525

496

417

455

490

484

425

441

393

101

80

88

84

57

69

88

91

101

73

93

74

1,747

1,729

1,686

1,646

1,594

1,528

1,685

1,667

1,633

1,594

1,542

1,502

280

262

256

241

231

225

272

275

266

235

243

237

180.2

173.5

168.8

167.3

166.7

169.7

178.0

176.6

175.0

176.5

177.7

184.2

187.2

183.1

176,9

175.6

173.3

176.8

175.4

185.5

177.0

179.7

180.9

185.9

29.22

30.40

29.57

29.46

28.59

29.62

27.97

28.92

31.75

30.27

29.91

33.97

33.02

35.41

33.62

31.50

26.64

33.94

25.98

31.08

32.60

30.71

30.72

34.91

Cholesterol

1.59

1.26

1.46

1.48

1.75

1.40

1.23

1.82

1.67

1.58

2.02

1.23

3.01

3.80

4.74

3.04

4.46

6.44

3.87

3.03

2.53

4.25

2.46

4.27

137.3

130.7

124.1

125.7

124.0

123.0

135.3

133.6

126.9

134.4

136.9

141.2

141.1

126.8

134.1

134.3

118.8

127.9

136.7

136.4

122.5

131.7

127.8

140.4

)mg/100ml

146.0

138.2

133.6

134.6

134.7

133.8

144.0

141.2

137.0

141.5

143.3

149.3

146.8

136.6

137.7

139.1

138.5

133.0

143.1

145.2

136.5

136.0

142.6

146.2

160,3

152.1

148.4

147.0

147.8

150.3

161.2

155.4

154.8

155.7

155.9

162.7

163.0

155.2

158.3

161.9

159.8

150.2

158.9

161.7

158.0

161.5

158.5

157.6

178,7

171.3

165.8

163.3

164.7

168.4

176.6

173.8

173.5

175.2

175.0

178.7

183.4

177.0

174.8

173.3

174.0

176.2

172.7

187.8

174.6

178.2

180.9

184.1

197.3

191.3

188.2

184.6

183.5

187.2

194.7

196.8

192.2

193.7

195.2

201.1

208.1

210.8

190.6

190.6

186.4

196.4

187.7

207.2

194.1

199.6

199.3

215.9

216.1

214.4

206.4

207.4

201.0

208.1

213.8

217.6

212.2

213.0

220.3

224.3

229.4

228.5

217.7

207.2

206.3

217.8

213.7

225.1

215.6

221.2

224.0

234.3

231.1

228.9

220.0

221.6

216,1

219.6

225.6

228.5

224.4

223.8

231.5

248,6

241.8

242.2

227.5

218.6

218.2

236.4

224.8

235.4

239.2

231.9

231.9

245.6

NOTE: n =sample size; N= estimated number of youths inthousands; ~=mean; sY=standard deviation ;sp=standard error of

the maan.

. . ,.

20
Tabla 10. WalQhtedmmplesize, m=ncholesterol.8 ndstan&rd error of themean foryouths Wd12-17vears, bve, sx, andannual family inmme:Unit& States,l*7O

-

12 years 13 years 14 years 15 years 16 years

3SXand annual family income

17 years

N x SF N F $2 N x % N J? SF N z $E N z SF

—Mole

I

Cholesterol in IWI1OO ml

All Incomes . . . . . . . .

L*I: thm $3,0W . . . . . . . . .

$3J200.34,999 . . . . . . . . . . .

$5,01X7.$9,8s9 . . . . . . . . . . .

$l0,0000rmcm . . . . . . . . .

Don’t know . . . . . . . . . . . . .

Blank orrafused . . . . . . . . . .

Female

Alllnc.mas . . . . . . . .

L**s than $3,000 . . . . . . . . .

$3,cmo-$4,999 . . . . . . . . . . .

$6,000.$B,999 . . . . . . . . . . .

SI0,0000rmOre . . . . . . . . .

Don’t know . . . . . . . . . . . . .

Blank orref used . . . . . . . . . .

2,032

—

180

306

669

575

55

45

181.3 1.40 I 2,005 174.7 I 1.17 1.9511 159.9 1.551.900 158.5 1.40 1.828 167.7 I 1.76 1.70

-

. _ _ —

f77.2

179.3

182.7

180.5

167.0

186.4

5.57 212

254

767

619

65

80

176.4 5.63

175.1 5.10

173.6 2.10

175.5 1.62

176.3 4.11

171.0 5.12

m

240

746

597

100

67

163.8

171.2

169.8

172.2

163.4

174.1

3.66

5..56

2.24

2.60

6.38

7.06

241

219

719

598

76

48

164.7

169.4

166.3

172.7

174.4

153.5

5.03

2.99

1.69

2.08

3.59

6.56

201

255

719

516

62

55 1

163.9 5.03

163.7 4.40

167.3 2.31

170.7 2.92

170.1 5.55

173.4 6.92

17s.1 1.86

17s.9 3.4s

172.6 3.22

177.3 2.66

179.5 2.92

177.8 3.64

188.5 11,50

226

245

692

479

49

74

178.2

167.0

169.2

171.6

163.0

176.1

3.70

5.08

1.90

2.99

9.10

B.14

3.56

1.95

Z.oa

5.13

‘1O.92

1,970 41,901 175.3

-

257

274

722

6KI

79

37

178.0

_

172.9

177.5

177.5

160.2

179.6

183,9

=L= T

177.7 1.74

166.9 4.31

179.6 2.71

181.3 2.31

176,22.68

183.1 9.08

176,2 11.03

1.59 1,851 176.8 1.59 1,7s9 1,746 134.5 1.31

. _ . . - - -

3.84 25a

4.33 301

2.50 802

2.00 484

4.39 46

42,82 35

213 154.s

3M 169.5

720 160,9

554 176.1

72 178.2

42 157.5

4.24

4.22

1.82

2.62

7.21

11.13

—

258

264

700

533

63

32

176.4

173.2

175.3

1s1.0

171.3

161.7

5.13

3.16

2.32

2.57

5.21

10.17

246

156

650

594

63

50

1S2

206

536

628

92

S2

176.7

194.9

182.9

1s3.0

190.5

197.5

6.15

7.04

2.43

2.29

5.61

9.69

NOTE: N = em!matednumber of youths in thousands;~ = mea., SF = standarderror of the mean.

Tablo 11,Welght8dsamplesize,mean cholesterol,and standarderror of the mean for youths aged 12-17 years,by age,tex, and education of parent United 8tates, 185$-70

Scx and education of parent

—

Mde Cholesterol In mg/100 ml

All aducationIJOUIIS .

Lessthan6ynars . . . . . . . . .

8.11 War$ . . . . . . . . . . . . . . .

12 years . . . . . . . . . . . . . . . .

13 yearaor mora . . . . . . . . .

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

Femalm

All education groups .

Lnssthan 8 years . . . . . . . . .

E.ll yams. . . . . . . . . . . . . . .

12v9mt . . . . . . . . . . . . . . . .

13ymrs0rm0r0 . . . . . . . . .

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

1,951 169.9 1.56 1,600 168.5

172 161.3 5.66 196 161.8

474 172.2 3.27 487 167.3

730 169.1 1.47 727 170.9 m

2,032 181.3 1.40 2,00% 174.7 1.17

176 177.1 4.77 175 166.8 3.79

543 182.3 2.89 502 176.6 3.24

736 180.S 2.04 760 175.0 2.2s Tl_ 1.40 1,636 167.7

4.10 217 164.1

2.70 474 167.0

1.96 630 168.6

562

16

182.5 I 2.96 I 527 I 174.6 I 2.24 549 172.2 2.29 472 169.6

25 157.4 18.05 16 144.7

1,901 175.3 1.59 1,651 176.8

2.28 480 169.1

12.26 35 182.7

1.59 1,769 178.1 4+

2.35 286 173.4 2.11

5.79 54 174.2 9.44

1.86 1.746 1S4.5 1.31

5.18 146 185.9 11.66

2.49 465 183.4 2.(33

2.54 525 164.7 2.62

4.17 542 161.9 2.67

25.53 67 209.1 17.72

186.2 45.40 23 182.1 9.27

1,970 178.0 I 0.98 I 1,946 I 177.7 I 1.74m Tr 6.16 167 175.2

2.80 453 173.2

2.66 623 177.0

1.32 612 163,8

211

430

729

509

174.1 4.58 228 172.9 8.39

176.1 2.82 507 177.4 1.70

178.8 1.86 727 161.3 2.43

180.2 1.84 463 175.3 2.45

41 I176.5 1G.39 97.- I .1 . 21 184.0 29.66 22 170.6 42.33 24 195.7 1 I

NOTE: N. tdtlmated number of youths in thousands; ~ = mean;s~ = standard error of the mean.

21

●
Table 12. Weighted sample size, mean cholesterol, and standard error of the mean for youths aged 12-17 years, by race, sex, annual

family income, and education of parent: United States, 1966-70

Variable

MALE

Annual family income

Lessthan $3,000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

.$3,000-.$4,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$5,000-$9,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$10,000 ormore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Education of parent

Lessthan8 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8-11 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

12years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

13yearsor more . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

FEMALE

Annual family income

Less than $3,000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$3,000-$4,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$5,000-$9,999 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$l0,000ormore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Education of parent

Lessthan8years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8-n years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

12years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

13 years or more . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Total White I

Negro

Cholesterolinmg/100m1

1,259

1,540

4,512

3,383

1,145

2,925

4,271

2,977

1,424

1,511

4,182

3,404

1,090

3,040

3,963

2,903

170.6

171.3

171.9

174.0

166.7

173.0

172.4

173.8

172.7

177.5

179.2

179.5

174.4

177.3

179.1

179.0

1.72

2.34

0.86

1.34

2.13

1.27

1.10

1.11

2.50

2.44

1.09

0.97

5.16

1,21

1.18

1.56

771

1,122

4,055

3,280

818

2,237

3,913

2,822

928

1,102

3,760

3,258

784

2,337

3,600

2,752

165.6

167.4

171.5

173.5

164.1

170.4

171.5

173.5

171.8

175.1

178.7

179.2

173.4

176.0

178.7

178.7

2.83

2.60

0.98

1.38

2.49

1.52

1.11

1.04

3.46

2.74

1.17

1.03

6.90

1.57

1.20

1.65

487

402

424

87

322

671

335

132

495

400

407

117

302

679

363

127

178.5

180.9

175.2

189.4

172.9

181.6

181.5

178.5

174.4

183.7

183.5

185.8

177.2

181.9

182.4

180.7

3.06

4.58

2.89

5.66

2.70

2.49

3.22

4.97

2.85

3.42

3,22

5.32

4.70

2.98

3.54

4.96

NOTE: N = estimated number of youths in thousands; ~ = mean;s~ = standard error of the mean,

22
Table 13. Weighted sample size, mean cholesterol, and standard error of the moan for youths aged 12-17 years, by we, race, sex, and mmud family income: United States, 1966-70

Race, sex, and annual

famOy income

Whltn male Cholesterol in mg/10D ml

All bwomes . . . . . . .

Lussthan $3,000 . . . . . . .

$3,000.$4,999 . . . . . . . . . .

$5,000.$9,999 . . . . . . . . .

$l0,0000rmOre . . . . . . . .

Don’t know . . . . . . . . . . . . .

Blank or refused . . . . . . . .

White female

AH fncomes . . . . . . .

Lessthan $3,000 . . . . . . . . .

$3,W0.$4,999 . . . . . . . . . .

$6,000.$9,999 . . . . . . . . . . .

$lO,OQO OrmOre . . . . . . . . .

Don’t know . . . . . . . . . . . .

Blank orrefused . . . . . . . . . .

168.8

.

155.2

165.6

169,4

172.2

162.2

173.7

176.0

-

163.6

167.2

179.9

176.3

173.B

156.3

176.9

.

174.5

192.3

171.9

171.2

171.2

.

177.0

.

166.7

174.9

192.0

172.7

166.9

.

1,646

153

151

553

578

E4

46

1,594

1,747 1.59 1.72S 1.594 166.: 169; 1.40

-

162;

162.,

166.(

169.[

167.,

173.4

1773

180.2 1.75[ 1.528

_

172,2

174.8

182.7

179.6

186,6

163.7

176.0

.

173.2

176.8

177.4

179.9

180,3

187.0

167.2

.

185,2

188.4

162.0

206.4

!88.1

.

I 75.4

—

172.4

176.9

178.3

171.4

.

,

173,5

.

170.4

172.3

173.1

175.3

175.4

168.6

176.6

.

160.9

176.4

180.2

176.5

179.2

172.0

183,1

.

185.4

182.3

179.1

.

.

.

1s5.5

.

175.8

190.4

182.6

162.9

.

.

1.26

9.80

6.84

2.28

1.90

4.62

4.66

1.82

.

5.20

2.82

2.28

2.72

10.76

11.62

3.8o

6.86

4.13

7.91

.

.

.

3.03

4.91

7.86

6.31

14.69

.

.

1,686

.

110

190

662

679

87

57

1,633

.

138

211

661

535

51

36

256

=

89

50

78

15

13

11

266

—

75

69

57

19

21

6

—

1.46

.

2.73

4.73

2.24

2.63

7.32

8.14

1.67

.

6.39

4.92

1.99

2.56

9.30

13.84

4.74

.

5.16

12.95

8.80

13.71

6.61

.

2.53

.

3.80

7.09

9.29

20.08

9.82

.

167.3

.

157.8

167.0

165.9

172,1

171.3

153.5

176.6

1.&

-

6.7:

3.71

1.9(

2.1/

3.54

6.5f

1.5:

=

6.3f

3,51

2.25

2.72

5.7s

13.18

3.04

.

6.20

5.17

7.73

14.29

.

4.25

9.21

5.59

9.14

t 0.62

.

.

—

. . _

111

209

786

567

41

43

1,665

7.71

3,86

1.94

2.04

6.66

11.23

1.23

127

1SC

681

606

58

76

1,667

129

211

632

501

67

55

1.542

3.69 142

5.23 181

2.11 540

2.62 459

6.84 37

6.92 66

2.02 1.502

175.5

162.[

169.<

170.s

162.E

174.t

184.2

=

173.5

186.8

183.2

182.1

191.3

199.5

176.8

7.84

5.35

2.03

288

11.C4

8.26

1.23

9.62

8.24

2.72

2.26

6.14

46.12

6.44

180

195

641

571

63

24

280

.

69

96

81

16

14

2

272

.

77

76

81

19

16

4

5.46

5.42

2.66

2.17

5.28

43.42

3.01

.

7.82

8.55

7.30

6.4o

42.62

.

3.87

4.06

6.49

8.51

8.93

●

.

160

229

729

4B2

36

31

262

.

85

60

78

9

6

3

275

.

108

72

74

9

8

4

18:

207

611

506

69

27

241

66

65

59

17

12

235

—

76

53

81

17

3

6

178.5

170.2

175.1

180.4

171.0

180.8

176.6

.

176.7

172.3

170.2

189.6

.

179.7

171.2

185.6

179.0

200.2

●

.

156

113

589

571

69

44

231

179.f

165.2

176.5

179.:

177.5

193.C

173.2

=.

166.9

168.E

178.0

.

.

1s0.9

.

177.6

189.3

180.2

183.8

179.2

.

5.2n 111

4.02 146

3.16 529

3.77 591

4.26 86

12.13 40

4.46 225

Negro male

All incomes . . . . . . . . . .

Less than $3,000 . . . . . . . . .

$3,000.$4,899 . . . . . . . . . . .

$B,000.$9,899 . . . . . . . . . .

$l0,0000rmOre . . . . . . . . .

Don’t know . . . . . . . . . . . . .

Slankorrefumd . . . . . . . . . .

Negro female

Alllncamec . . . . . . . . . . .

Lets than $3,OOO . . . . . . . . .

$3,000.$4,999 . . . . . . . . . . .

$5,0Q0.$8,999 . . . . . . . . . . .

$l0,0000rmOre . . . . . . . .

Don’t know . . . . . . . . . . . . .

Slankorrefwad . . . . . . . . . .

.

72

54

80

10

15

243

.

89

52

57

23

14

7

10.81 85

3.84 58

7.40 48

.

17

.

12

6

2.46 237

182.0

177.7

154.3

187.2

163.6

.

1s5.9

10.55

12.20

10.67

12.65

40.21

.

4.27 _

2.57 71

8.01 60

5.48 58

13.58 30

8.08 6

.

12

181.7

190.4

180.2

197.5

.

190.9

5.66

9.75

7.42

11.59

.

— 18.72

NDTE: N~estlmated numbrof youths inthousa"ds; ~=mean; s~=Sandard error of the mean.

23
Table 14. Wolghtedmmple size, mmncholesterol, andstandard error of themean forvouthsaged 12-17years, bvaw, mw, mx, and&u-tion ofwrenC United States, l966-7O

12 years I 13 years I 14 years I 15 yews I

16 year% I17 years

Sex and education of parent

White male Meancholesterol inmg1100m1 .

Alledu@ ion groups .

Lessthan8 years . . . . . . . . .

S-n years . . . . . . . . . . . . . . .

12y.sars . . . . . . . . . . . . . . . .

13years0rm0re . . . . . . . . .

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

White female

Alleducatlongrourx .

Lessthan 8 years . . . . . . . . .

S.ll years . . . . . . . . . . . . . . .

12years . . . . . . . . . . . . . . . .

13 yearsor more . . . . . . . . .

Unkncr.+n . . . . . . . . . . . . . . .

Negro male

Alleduwdion groups .

Lessthan 8 years . . . . . . . . .

S-n years . . . . . . . . . . . . . . .

12years . . . . . . . . . . . . . . . .

13 years or more . . . . . . . . .

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

Negro female

All education groups .

Lessthan 8 years . . . . . . . . .

%lly ears. . . . . . . . . . . . . . .

12y0ars . . . . . . . . . . . . . . . .

13 yearsor more . . . . . . . . .

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

180.2 1.59 173.5 1.26 1,586 188.8

145 169.8

341 167.8

632 VX3.6

523 172.2

14 .

1.633 175.0

107 166.3

429 175.9

548 174.6

440 176.0

9 ●

256 176,9

27 16S.6

130 183.6

Ed 173.9

20 170.3

11 “

25$ 177.0

167.3! 1.46 1,594 166.7 1,628 169.7 1.40

-

8.34

2.87

2.63

2.07

11,41

1,23

I ,747

.

119

412

675

528

13

1,886

.

lt%

379

650

454

28

230

-

57

130

53

32

3

272

1.728 1.46

.

6.44

3.08

1.46

2.21

.

1.67

6.93

2.54

2.36

3.87

.

4.74

.

39.5a

7.94

9.17

12.63

.

2.53

.

3.45

3.85

6.37

13.40

.

1,546

.

139

280

652

461

14

I .594

.

127

479

578

391

20

241

.

57

103

58

6

3

235

.

47

109

63

14

3

—

1.76

.

4.96

2.40

3.13

2.18

5.44

2.02

.

9.93

2.92

2.75

4.50

28.73

4.46

.

6.61

10.28

7.43

11.79

.

2.46

. . .

173.8

176.7

160.3

162.8

.

176.0

.

173.3

174.9

179.5

180,3

177.3

187.2

.

184.6

193.5

1S0.8

175.4

.

175.4

5.67

3.06

2.31

2.95

.

1.23

-

7.04

3.06

2.15

2.14

16.77

3.01

.

5.25

7.43

5.11

10.08

●

3.87

104

381

713

501

19

1,557

.

182

266

661

452

16

262

.

71

102

64

23

3

276

.

46

147

85

11

5

162.5

176.2

173.5

174.2

177.4

176.6

172.2

174.6

160.2

174.4

.

163.1

=

173.1

183.4

192.7

182.3

.

186.5

3.04

3.72

2.43

2.47

9.75

1.62

.

8.01

2.26

2.46

2.56

.

3.80

.

7.W

4.92

8.79

8.06

.

3.03

+

160.5 5.85

164.3 3.49

lm.5 1.92

158.2 2.24

149.5 13.96

176.5 1.58

170.1 9.25

176.8 2.58

179.0 2.62

174.6 1.43

. .

175.6 3,04

163

371

E80

446

28

1,542

106

349

572

490

24

231

161.3

167.3

167.4

167.9

166.6

177.7

.

176.1

171.3

176.0

183.3

200.7

173.3

143

342

632

2a3

49

1,602

-

96

344

491

615

56

225

188.3

167.6

l&3.8

173.0

175.0

184.2

166.4

182.3

184.1

181.9

217.2

176,8

19.16

2.42

2.46

2.48

23.21

6.44

. .

46

103

46

27

7

243

173,8

155.9

182.3

163.7

.

180.9

62

104

31

23

6

237

170,6

183.1

169.6

178.1

.

165.9

7.77

7.71

10.40

17.64

.

4,27

165.0 4.43

176,8 4.06

184.0 6.53

. .

. .

179.7 4.25

46

96

79

35

15

177.2

176.8

173.3

lffl.5

175.0

2.06

7.21

9.40

7.32

12.16

175.6

165.1

192.2

,

<

13.86

5.57

5.13

.

. -L53 173.1

186 1s0.5

71 176.5

25 171.5

12 “ ---L 178,0 4.41

178.1 7.27

180.4 6.45

196.5 16.20

. .

61

104

50

18

10

173.5

179.3

187.7

.

.

6.59

3,82

6.79

.

.

—

50

117

35

24

12

—

167.0

187.5

192.7

173.4

.

12.M

6.76

11.76

7.27

●

NOTE: N=estlmated numberof youths lnthoumnd%; ~=mean; s~=flandard error of the mean.

24
Table 15. Mean cholesterol levels and standard deviations of the population

1960-62

distribution foraduks, by sex and age: Unitad States,

Age

18-24 years

25-34 yaars

35-44 yaars

45-54 years

55.64 yaars

65-74 years

75-79 years

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

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

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

., ...,.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

.

,. .,..,. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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

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

lMgper~OOml.

NOTE; X=mean; sx=standard deviation.

Men

178.1

205.9

225.8

230.5

232.8

229.5

224.5

Sx

40.7

44.6

49.4

45.6

49.0

47.3

48.7

Women

184.7

197.9

213.6

236.8

262.3

265.7

245.3

Sx

47.9

41.9

45.3

50.0

63.0

58.8

65.7
APPENDIX I

TECHNICAL NOTES ON METHODS

The Survey Design

The sampling plan of Cycle III of the Health

Examination Survey followed a multistage, stratified probability sample of clusters of households in land-based segments in which a sample

of the U.S. population (including Alaska and

Hawaii) aged 12 through 17 years was selected.

Excluded were those youths confined to institutions and those residing on any of the reservation lands set aside for use by American Indians.

The sample design of Cycle III is similar to

that of Cycle II in that it uses the same 40

sample areas and the same segments. The decision to incorporate this feature into Cycle III

was not made prior to the selection of the Cycle

II sample, although it is consistent with the

initial concept of a single program for persons

6-17 years old. The final decision to use this

identical sampling frame was made during the

operation of the Cycle II program.

The successive elements for this sample design

are primary sampling unit; census enumeration

district; segment (a cluster of households);

household; all eligible youths; and finally, the

sample youth. Every eligible youth within the

defined population has a kfiown and approximately equal chance for selection into the

sample.

The steps of drawing the sample were carried

out jointly with the U.S. Bureau of the Census;

the starting points were the 1960 decennial

census lists of addresses and the nearly 1,900

primary sampling units (PSU’S) into which the

entire United States was divided. Each PSU is a

standard metropolitan statistical area (SMSA), a

count y, or a group of two or three contiguous

counties. These PSU’S were grouped into 40

strata so that each stratum had an average size of

about 4.5 million persons. This grouping maximized the degree of homogeneity of the PSU’S

within each strata with regard to the population

size, degree of urbanization, geographic proximity to one another, and degree of industrialization. The 40 strata were then classified into four

broad geographic regions of 10 strata each and,

within each region, cross-classified by four population density classes and by the rates of

population change from 1950 to 1960. Using a

modified Goodman-Kish controlled-selection

technique, one PSU was drawn from each of the

40 strata.

The sampling within the PSU’S was carried

out in several steps. The first step was the

selection of census enumeration districts

(ED’s)–small, well-defined areas of about 250

housing units. The entire nation was divided into

ED’s for the 1960 population census, and each

ED was assigned a “measure of size” equal to

the rounded whole number resulting from a

“division by nine” of the number of children

aged 5-9 in the ED at the time of the 1960

census. A sample of 20 ED’s in the sample PSU

was selected according to a systematic sampling

technique, with each ED having a probabilityy of,

selection proportional to the population of

children aged 5-9 years at the time of the 1960

census date. From each ED a random selection

of one measure of size (segment) was taken.

Minor changes required in the Cycle III design

were (1) that it be supplemented for new

construction to a greater extent than had been

necessary in Cycle II and (2) that reserve

segments be added. Although it was the plan for

Cycle III to use the Cycle II segments, it was

recognized that within several PSU’S additional

reserve segments would be needed to avoid the

26
risk of having an insufficient number of examinecs. This was prompted by the fact that four

of the PSU’S in Cycle II had yields of less than

165 eligible children and several others were

marginal in their yield. In addition, there was a

3-year interval between Cycle II and Cycle III,

so that it was quite possible” for some segments

to have been completely demolished due to

highway construction or urban redevelopment.

The time available for examinations at a

particular location, or stand, is necessarily set far

in advance of any preliminary field work at the

stand. Therefore, the number of examinations

that can be performed at a particular location is

dependent on the number of examining days

available. At the majority of locations, the

number of days available, excluding Saturdays,

is 17. At the rate of 12 examinations each day,

this provides for 204 examination slots. Examinations are conducted on Saturdays if necessary.

Because of rescheduling for cancellations or

no-shows, the maximum number of youths that

is considered for inclusion in the sample is 200.

When the number of eligible youths exceeds the

maximum, subsampling is performed to reduce

the number to manageable limits. This is accomplished through the use of a master list, which is

a listing of all eligible youths in order by

segment, serial number (household order within

segment), and column number (order in the

household by age). After the subsampling rate

has been determined, every nth name on the list

is deleted, starting with the yth name, y being a

randomly selected number between 1 and n.

Youths who are deleted from the Cycle 111

sample but who were examined in Cycle II and

any twin who may have been deleted are

scheduled, if time permits, for an examination

to be included only in the longitudinal study

portion or twin study portion of the survey.

Their data are not included in the report as part

of the regular sample.

Since the strata are roughly equal in population size and a nearly equal number of sample

youths were examined in each of the sample “

PSU’S, the sample design is essentially selfweighting with respect to the target population;

that is, each youth 12 through 17 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 “simiku-” respondents.

Here “similar” respondents were judged to be

examined youths in a sample PSU having the

same age (in years) and sex as those not

examined in that sample PSU.

The poststratified ratio adjustment used in

Cycle III 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, and it made the final sample

estimates of population agree exactly with independent controls prepared by the U.S. Bureau

of the Census for the noninstitutional population of the United States as of March 9, 1968

(approximate midsurvey point) by color and sex

for each single year of age 12 through 17. The

sampling weight of every youth examined in

each of the 24 age, race, and sex classes is

adjusted upward or downward so that the

weighted total within the class equals the independent population control.

A more detailed description of the sampling

plan and estimation procedures is included in

Vital and Health Statistics, Series 2-Number

43,38 and in Series l-Numbers 11, 53, and 8A,

which describe the plan and operation of the

first three cycles of the HeaIth Examination

Survey.

Some Notes on Response Rates

As mentioned previously, the sample designs

of the second and third cycles of the HES were

similar. Differences did occur, however, in response rates of various subgroups of these

samples, and these differences deserve some

consideration here.

Most importantly, the number of youths

selected for examination increased from 7,417

in Cycle II to 7,514 in Cycle HI. The response

rate—i.e., the number of youths selected who

were actually examined—decreased from 96 percent in Cycle II to 90 percent in Cycle III. Of

the youths examined in Cycle II, 13.9 percent

were Negro, compared with 14.8 percent of

Note.–A list of references follows the text.

27
those examined in Cycle III. This difference

does not reflect a difference in the percentage of

Negro youths selected for examination, but

rather, a smaller decrease in response rate for

Negro youths between the two cycles than was

the case for white youths. In actuality, 13.8

percent of the sample selected for examination

was Negro in Cycle III, corresponding to 13.5

percent in Cycle II. However, whereas the

response rate for white youths dropped from

95.6 percent in Cycle II to 89.1 percent in Cycle

III, the response rate for Negro youths dropped

far less, from 98.4 percent to 96.6 percent.

Thus, relatively better response from the Negro

portion of the sample in Cycle III increased their

percentage of actual examinations as compared

with the previous cycle.

Examination of sample sizes in this report

clearly shows that at every age group, fewer

females than males were actuaIly examined.

This, again, is not attributed to differences in

numbers of youths selected in the sampling

design, but rather to the following differential

response rates between males and females:

Age Male Female

Total . . . . . . . . . . . . . . . . . . . . . . 91.4 88.7

12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93.5 91.3

13 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93.2 91.9

14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91.7 90.7

15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91.6 87.9

16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89.8 87.7

17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87.6 81.8

Note that at each age group the response rate for

males exceeded that for females.

A similar analysis of response rates can be

done by age, race, and sex, as follows:

Age

White Negro White Negro

male male female female

Total . . . . . . . . . 90.5 97.6 87.4 95.8

12 . . . . . . . . . . . . . . . 92.6 99.0 90.1 98.9

13 . . . . . . . . . . . . . . . 92.5 98.8 91.1 96.8

14 . . . . . . . . . . . . . . . 91.0 97.8 89.6 96.2

15 . . . . . . . . . . . . . . . 90.7 97.7 86.4 98.6

16 . . . . . . . . . . . . . . . 89.2 95.0 86.6 93.0

17 . . . . . . . . . . . . . . . 86.5 95.8 80.2 91.4

The above clearly indicates that for all ages

under consideration in Cycle III of the HES, the

response rate for Negro youths exceeded that

for white youths of the same sex and age.

Reasons for differences in response rates are

many, but may range from the incentive to get

examined in order to miss a day of school, to

fear of the examination itself, to inhibitions

with respect to being examined. The worst

response rate was recorded for the oldest females, that is, those aged 17 years.

Parameter and Variance Estimates

Because each of the 6,768 sample children has

an assigned statistical weight, all estimates of

population parameters presented in HES publications are computed taking this weight into

consideration. Thus, ~, the estimate of a population mean p is computed as follows:

n

x

z wjx~ j=1

= ZWj

where Xi is the observation or

taken on the ith person and Wi is

weight assigned to that person.

measurement

the statistical

The HES has an extremely complex sampling

plan, and obviously, by the very nature of the

sample, the estimation procedure is complex as

well. For estimating the reliability of findings, a

method is required that “reflects both the losses

from clustering sample cases at two stages and

the gains from stratification, ratio estimation,

and poststratification.”8 9

The method for estimating variances in the

HES is the half-sample replication technique.

The method was developed at the U.S. Bureau

of the Census prior to 1957 and has at times

been given limited use in the estimation of the

reliability of results from the Current Population

Survey. This half-sample replication technique is

particularly well suited to the HES because the

sample, although complex in design, is relatively

small (6,768 cases) and is based on but 40 strata.

This feature permitted the development of a

variance estimation computer program that produces tables containing desired estimates of

28
aggregates, means, or distributions, together

with a table identical in format but containing

the estimated variance of the estimated statistics. The computations required by the method

are simple, and the internal storage requirements

are well within the limitation of the IBM 360-50

computer system used at the National Center for

Health Statistics.

Variance estimates computed for this report

were based on 20 balanced half-sample replications. A half sample was formed by choosing

one sample PSU from each of 20 pairs of sample

PSU’S. The composition of the 20 half samples

was determined by an orthogonal plan. To

compute the variance of any statistic, that

statistic is computed for each of the 20 half

samples. Using the mean, xi, asan example, the

weighted mean of the entire undivided sample

(~) is computed. The variance of the mean is the

mean square deviation of each of the 20

half-sample means about the overall mean.

Symbolically,

20

i~l (~. - 5?)2

Var(x)= Z.

and the standard error of the mean is the square

root of Var(~). In a similar manner the

standard error of any statistic may be computed.

A detailed description of this replication

process has been published in Vital and Health

Statistics, Series 2-Number 14.39

Standards of Reliability and Precision

All means, variances, and percentages appearing in this report met defined standards before

they were considered acceptably precise and

reliable.

The rule for reporting means and percentiles

consisted of two basic consecutive criteria: that

a sample size be at least five; and that the

estimated coefficient of variation (i.e., the standard -grror of the mean divided by the mean, or

(SX /X) be less than 25 percent. Thus, if the

sample size was too small, or if, given adequate

sample size, the variation with respect to the

mean was too large, then the estimate was

considered neither precise nor reliable enough to

meet the standards established for publication.

Imputation

In addition to the subject nonresponse discussed above, the problem of item nonresponse

merits consideration here. In this situation,

information about a respondent is complete

with the exception of a missing cholesterol

value.

A regression method was initially chosen for

the imputation of missing cholesterol values. If

other variables could have been found which

correlated with cholesterol, this other information could have been effectively used in a

regression scheme of imputation. Two “best

possible” predictor variabIes were chosen in

triceps and subscapular skinfolds. After standardizing these two variables by age, race, and sex

group, a regression was run. However, the

resultant multiple R of O.1316 was not considered to be sufficiently high to justify a

regression approach to replacing missing cholesterol values.

Instead, the technique of replacing a missing

datum by the value recorded for a randomly

selected respondent of the same age, sex, and

race was employed. When only one of the two

cholesterol values was missing, the recorded

measurement was substituted for the unknown

value. This occurred in only one instance.

Imputation where there was no value recorded

for examinees was necessary in 175 cases (i.e.,

for 2.6 percent of total respondents).

Uuo

29
APPENDIX II

DEMOGRAPHIC VARIABLES

Regional and demographic characteristics by

which the population has been classified for this

report are defined as follows:

Age and sex. –Population was classified into

12 age-sex groups-the six ages 12-17 years by

sex. Birth certificates verified the age of 92

percent of the youths. Age stated by the parents

was accepted as the true age for the other 8

percent. Age is expressed as years attained at last

birthday.

Race. –Serum cholesterol value was reported

by race for white and Negro youths. Youths of

other races were not sampled sufficiently for

comparison purposes and represented only 0.55

percent of the sample.

Re.~-on.–Regional data are presented for four A

regions of the continental United States.

Re~.on

Northeast

Midwest

South .

. . .

. . .

. . .

States Included

Maine, Vermont, New

shire, Massachusetts,

Island. Connecticut.

HampRhode

New

York, Pennsylvania, New Jersey

Minnesota, Wisconsin, Michigan, Iowa, Missouri, Illinois,

Indiana, Ohio

Delaware, Maryland, Virginia,

District of Columbia, West

Virginia, Kentucky, Tennessee, North Carolina, South

Carolina, Georgia, Florida,

West . . . . .

Alabama, Mississippi, Arkansas, Louisiana

Washington, Oregon, Idaho,

Montana, North Dakota,

South Dakota, Wyoming,

Nebraska, Kansas, Colorado,

Utah, Nevada, California, Arizona, New Mexico, Texas,

Oklahoma, Alaska, Hawtil

Family income. –The income recorded was

the total income received during the past 12

months 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 its own farm

or business, in which case net income was

recorded.

Education of parent or guardian.–This item

was recorded as the highest grade that had been

completed in school. The only grades counted

were those that had been completed in a regular

school in which persons were given formal

education: graded or private schools, either day

or night schools, with either full-time or parttime attendance. 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.

000
APPENDIX Ill

TECHNIQUES OF MEASUREMENT

AND QUALITY CONTROL

MEASUREMENT

The HES Blood-Drawing Technique and Its

Historical Development

For a variety of reasons, it was decided not to

‘ attempt to draw blood specimens from children

6-11 years of age in Cycle II. The children

included in the national probability sample came

from all regions of the country and all cultural

and socioeconomic groupings and ways of life. It

was assumed, therefore, that some had never

been to a physician before and that others

would have very bad memories of and associations with such visits. In addition, because the

sample covered the entire spectrum of behavioral and physical development extant in the

United States, severe technical and behavioral

problems resulting from immaturity of 6- and

7-year-olds would be likely. It was believed that

fear or extreme distaste for having a blood

sample drawn on the part of many potential

subjects might severely affect the response rate,

which is so crucial to a survey like this. When it

is remembered that the overall response rate for

Cycle II was a remarkable 96 percent, it is

difficult to argue with this line of reasoning.

Now, of course, it can never be known how

great a diminution of the response rate would

have been caused by the inclusion of a blood

sample from younger children in Cycle II.

In the early planning stages of Cycle III, it

was decided to obtain a blood specimen from

the youths 12-17 years if at all feasible, that is,

primarily if the price in terms of diminished

response rate and cooperation of the examinees

would not be too high. Accordingly, in three

separate pretests, investigations were conducted

regarding the problem of developing a satisfactory blood-collection technique for this age

group and examination setting. What was desired

was to draw the optimum amount of blood,

without causing emotional upset to the examinee, or without affecting his performance in

any of the procedures to follow. The amount of

usable blood that could “be drawn posed a

limiting factor on the number of blood chemistry tests that could be performed and greatly

influenced the acceptance or rejection of an

entire possible area of’ the examination, such as

the nutritional assessment. Logistical problems

also had to be resolved involving the handling,

separating, and packaging of drawn blood so

that there would be a minimum of blood loss

and packaging error. For the refrigerated but

unfrozen blood, time from shipment to delivery

was critical; therefore, arrangements had to be

made with postal authorities to assure prompt

delivery to the laboratories in order to avoid

spoilage.

There was a trial-and-error process, and there

was good advice and help from many sources in

developing a satisfactory blood-drawing technique. The chief sources of help, outside of the

immediate HES technical staff, were Dr. Wilma

Bias and Dr. Bernice Cohen of The Johns

Hopkins University; Dr. Gerald Cooper, Chief of

Laboratories, Center for Disease Control, Public

Health Service, Atlanta, Ga.; the many teenage

subjects during our pretest who gave valuable

suggestions and who pointed out, either as overt

advice or by their immediate reactions, specific

31
points to be avoided; and, finally, the professional and technical division of the BectonDickinson Company, Rutherford, N.J. The

latter, through several personal visits by a

representative of their technical division, not

only gave excellent technical advice on bloodcollection techniques and the use of alternative

equipment, but also devised a special fitting that

made the transfer from one vacutainer tube to

another much smoother.

During the pretesting, it was learned that

many subjects did not like to see any part of the

blood-drawing procedure, including their own

blood in tubes. Therefore, a technique was

employed that minimized the subject’s attention

to the operation. Effective screening was

achieved by having the subject lie down and by

draping and keeping the arm and tubes well

below the level of the examination table. After

the skin area was cleansed with alcohol, the

blood was drawn from the antecubital fossa by

the physician-nurse team. At the discretion of

the physician, a tourniquet was used to fill the

vein; however, once the needle was inserted into

the vein, the tourniquet was taken off the arm

so that the blood flowed freely.

A B-D blood culture needle and tube were

used to draw blood. Using the specially prepared

link fitting, the nurse inserted the short needle

into a vacutainer tube holder. The tube was

clamped with a hemostat until the vein was

punctured and the vacutainer was inserted into

the holder.

From the one free-flowing venipuncture, a

total of only 55 cm3 of blood was collected in

four separate vacutainer tubes from all male and

almost half of the female subjects. (The difference was that all males had a separate specimen

drawn to be frozen and stored as plasma for

future testosterone determination and almost

half of the females provided a replicate blood

specimen for quality control of the laboratory

determinations; the remaining females had 40

cm3 drawn.)

Each test tube was labeled with the examinee’s number and left in the test-tube holding

rack at room temperature for 1 hour. The nurse

then placed the tubes in the laboratory refrigerator, along with 10 extra examinee identification

labels for use by the technicians.

An analysis that attempts to estimate the

impact of the addition of a blood sample on the

Cycle III sample response rate is in progress.

Cholesterol Chemistry Determinations

The serum samples were shipped to the Lipid

Standardization Laboratory at the Center for

Disease Control in Atlanta, Ga., where they were

kept frozen until assay.

After being thawed, samples were divided and

stored in two vials. All sample vials were then

randomized over a 6-day period so that a pair

of duplicate samples might have been analyzed

on the same day or as many as 6 days apart.

A semiautomated method based on the

AbelI-Kendall procedure was employed to measure total cholesterol. Determinations were

carried out on an assembly-line basis so that two

analysts could analyze more than 120 samples in

duplicate per day.

MONITORING SYSTEMS

In addition to the sampling considerations

already discussed, the quality of data collected is

also a special concern. One of the main purposes

of the monitoring system employed in the

survey was to indicate whether the measurements produced by our measurement process

attained the desired quality. A second major

purpose was to make possible quantitative summary descriptions of residual measurement

errors to aid in the interpretation of survey data.

The monitoring system as applied to the

taking of blood samples consisted of a formal

system of replicate examinations (described later

in this appendix). Replicate measurements are

useful for a variety of reasons; for example, as a

means of increasing precision of estimates of

individual measurements, as a training technique, and as a monitoring system that includes

the objective of overall evaluation of measurement errors. These objectives are not incompatible, and replicate data collected primarily for

one of these objectives often indirectly, if not

directly, accomplish one or both of the remaining two. For this reason replicate data are most

often collected with a combination of these

objectives in mind.

32
Methods of Taking Replicate Measurements

A major source of uncertainty in estimates

derived from replicate measurements is in the

inability to make the replicate measurement

under precisely the same conditions and in the

same manner as the original measurement. This

uncertainty is difficult to evaluate, and most

attempts are restricted to subjective statements

concerning the direction and/or size of the bias

and the need for concern in the analysis of data.

In this study two extra blood samples were

drawn from a subsample of Cycle III examinees

and were included in the shipment sent for

processing to the Lipid Standardization Laboratory at the Center for Disease Control in

Atlanta, Ga. Replicate blood samples were taken

from the same venipuncture as the regular blood

samples and, from shipment to final processing

at the CDC, were treated the same as the original

samples. These replicates were labeled with

dummy examination identification numbers and

were recorded by the nurse in a replicate log

book. All samples were submitted for laboratory

analysis with no indication that any two samples

came from the same examinee. Each replicate

was analyzed as usual, where each sample was

split by the technician and duplicate determinations were performed; if a difference greater

than 9 mg/100 ml was found (it was usually a

reading or recording error), a second set of

duplicate determinations was performed. The

analyses of replicates and originals were performed under identical laboratory conditions by

the same technician in a true double-blind

manner.

Cycle III examinees were chosen systematically for replicate blood determinations. On

every third day for the first 15 days of each

examination center, two extra blood samples

were drawn (preferably from girls) for the

replicate study. Since in a voluntary survey it is

impossible to follow a statistically random process in scheduling subjects, the replicate desi~

did not ensure that its subjects would be

“representative” of those in the larger Cycle HI

Health Examination Survey. It is felt, however,

that this is not a crucial issue since the matter of

concern in undertaking the replicate study is not

the determination of possible differences in the

values of the measurements, but rather the

determination of possible differences in errors

associated with the measurements.

Results of the Replicate Study for Cholesterol

Two readings were made of the original split

sample obtained for each of the 6,592 examinees (97 percent of the total sample) by the

same technician. An extra blood sample was

drawn for replicate studies on 424 examinees, of

which 98 percent were adequate.

Frequency and percent distributions of the

absolute differences between the duplicated

determinations on the original specimen and also

between the duplicated determinations on the

replicate and original specimens are presented in

table I. The first two columns represent the

differences between the duplicated determinations on the original specimen; the second two

columns represent the differences between the

first recorded determination values of the original specimen and that of the replicate specimen;

and the third two columns represent differences

between the second (or duplicated) recorded

wdues of the original and replicate specimens.

As a summary statistic of the distribution of

differences between replicate and original

cholesterol determinations presented in table I,

we have computed V, the percentage technical

error of measurement which is given by

where

n

d:

x

is the number of pairs of measurements in

the study,

is the square of the difference between

members of the ith pair of measurements

(i=l,...,n), and

is the arithmetic mean of the 2n measurements in the study.

The percentage technical error, V, can be interpreted as a “coefficient of variation” and is a

33
Table 1. Fraquancy and parcent distribution of absolute differences betwean duplicated determinations of original specimans and

batwaan original and replicated specimans

Absoluta difference

(mg/100 ml)

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

lo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

13 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

19 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

21 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

22 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

23 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

24 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

28 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

30 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

31 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

33 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

35 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

37 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3a . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

39 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

43 . . . . ..-. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

44 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

47 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

49 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

50 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

53 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

58 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

59 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

69 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

71 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

73 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

75 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

79 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

80 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

82 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

91 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

101 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Difference betwean

duplicated determinations of original

specimans

Frequency

6,592

996

1,285

1,037

881

752

510

390

308

225

141

43

1

4

4

1

1

2

1

h1

2

1

1

1

1

1

1

1

of total

100.0

15.1

19.5

15.7

13.4

17.4

7.7

5.9

4.7

3.4

2.1

0.7

0.1

0.1

.-

Difference betwaan original and replicated

specimens

First determinations

Frequency

408

32

46

57

40

52

34

14

21

28

16

3

5

14

6

4

4

2

5

2

3

1

3

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

Percent

of total

100.0

7.8

11.3

14.0

9.8

12.7

8.3

3.4

5.1

7.1

3.9

0.7

1.2

3.4

1.5

1.0

1.0

0.5

1.2

0.5

0.7

0.2

0.7

0.2

0.2

0.2

0.2

0.2

0.2

0.2

0.2

0.2

0.2

0.2

0.2

0.2

0.2

0.2

jecond determinetions

Frequancy

407

35

46

37

43

42

34

25

27

22

17

15

12

11

6

5

6

6

2

1

1

1

1

1

2

1

2

1

1

1

1

1

1

Percent

of total

100.0

8.6

11.3

9.1

10.6

10.3

8.4

6.1

6.6

5.4

4.2

3.7

2.9

2.7

1.5

1.2

1.5

1.5

0.5

0.2

0.2

0.2

0.2

0.2

0.5

0.2

0.5

0.2

0.2

0.2

0.2

0.2

0.2

34
dimensionless constant. It essentially describes

the size of measurement error relative to the

mean value of a measurement. As one measure

of the differences between specified determinations, the values of V are given below.

Specified Determinations v

First determinations on original and replicate specimens 4.7 percent

Second determinations on

original and replicate

specimens 4.6 percent

Duplicated determinations on

original specimen 1.9 percent

The reason for the contrast in V in the figures

above is that the original split sample was

subject to a repeat analysis if the readings

diverged by more than 9 mg percent. Cholesterol

values were not as easily replicated at the Center

for Disease Control as uric acid values had

been.g When the cumulative frequency and

percent distributions in table I are examined, it

is found that more than 15 percent of each of

the two distributions on the right side of the

table are above the 9 mg/100 ml level. However,

the fact that the coefficient of variation is less

than 5 percent in each case above does attest to

the overalI reproducibility of cholesterol.

Data Handling Verification

Quality control considerations were not confined to the laboratory. Data were subject to the

possibility of error every time a human hand

touched a keyboard or moved a pencil across a

page. After the data had been put on punchcards, they were transferred to magnetic tape.

Subsequent handling of the data by programmers and transcription by clerks provided

other sources of error.

To verify all operations, the entire cohort of

16-year-old Negro maIes was subjected to a

thorough independent manual audit. The computer tape printout of each subject’s serum

cholesterol value was listed opposite his identification. These were individually checked against

the values originally recorded at the Center for

Disease Control. The mean was then computed

manually on the desk calculator and proved

identical to the computer’s mean value.

In addition, all age, race, and sex identification for members of this cohort were found to

correspond exactly to the information given on

the household interview forms completed by

census interviewers.

000

*U.S. GOVERNMENT PRINTING OFFICE: 1976– 21O-9SLS7

35
Series 1.

Series2.

VITAL AND HEALTH STATISTICS PUBLICATIONS SERIES

Formerly hblic Health Service Publicatwn No. 1000

Programsand Collection l+ocedures.-Reports which describe the general programs of the National

Center for Health Statistics and its offices and divisions, &ta collection methods used, definitions, and

other material necessary for understanding the data.

Data EvaluationandMethods Research.-Studies of new statistical methodology including experimental

Sm”es3.

Series4.

tests of new survey methods, studies of vital statistics collection methods, new analytical techniques,

-. -.

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

Analytical Studies.–Reports presenting analytical or interpretive studies based on vital and health

statistics, carrying the analysis further than the expository types of reports in the other series.

Documents a,~d Comms”ttee Reports. –Fd reports of major committees concerned with vital and

health statistics, and documents such as recommended model vital registration laws and revised birth

and death certitkates.

Series 10. Dataporn the Health Interview Survey.-Statistics on illness; accidental injuries; disability; use of

hospital, medical, dental, and other services; and other health-related topics, based on data collected in

a continuing national household irkterviewsurvey.

Sert”es11. Dataporn the Health Examination Survey.-Data from direct examination, testing, and measurement

of national “samplesof the civilian, noninstitutionalized population provide the basis for two types of

reports: (1) estimates of the medically detlmed prevalence of ipecitlc diseases in the United States and

the distributions of the population with respect to physical, physiological, and psychological characteristics; and (2) analysis of relationships among the various measurements without reference to an

explicit ftite universe of persons.

Series 12. Datafrom the InstitutionalizedPopulation Surveys.–Discontinued effective 1975. Future reports from

these surveys will be in Series 13.

Sers”es13. Data on Health Resources Utikration.–Statistics on the utilization of health manpower and facilities

providing long-term care, ambulatory care, hospital care, and family planning services.

Series 14 Data on Health Resources: Manpower and Facilities.–Statistics on the numbers, geographic distribution, and characteristics of health resources including physicians, dentists, nurses, other health occupations, hospitals, nursing homes, and outpatient facilities.

Series 20. Data on Mortality.-Various statistics on mortality other than ss included in regular snnual or monthly

reports. Special analyses by cause of death, age, and other demographic variables; geographic and time

series analyses; and statistics on characteristics of deaths not available from the vital records, based on

sample surveys of those records.

Sers”es21. Dataon Natality, Marn”age,and Divorce. –Various statistics on natality, marriage, and divorce other

than as included in regular annual or monthly reports. Special analyses by demographic variables;

geographic and time series analyses; studies of fertility; and statistics on characteristics of births not

available from the vital records, based on sample surveys of those records.

Series 22. Datufrom the NationalMortality and Natality Surveys.–Discontinued effective 1975. Future reports

from these sample surveys based on vital records will be included in Series 20 and 21, respectively.

Serz”es23. Dataj+om the Nats”onalSurvey of Family Growth. –Statistics on fertility, family formation and dissoP lution, family planning, and related maternal and infant health topics derived from a biennial survey of

<.+

., a nationwide probability sample of ever-married women 15-44years of age.

For a list of titles of reports published in these series, write to: Scientific and Technical Information Branch

National Center for Health Statistics

Public Health Service, HRA

Rockville, Md. 20852
POSTAGE AND FEES PAID

U.S. DEPARTMENT OF

[’. S DE PARTMENT OF HEW

HEALTH, EDUCATION, AND WELFARE

Public Health Service HE W390

Health Resources Administration

5600 Fishers Lane THIRD CLASS

Rockville, Md. 20852 BLK. RATE

OFFICIAL BUSINESS

Penalty for Private Use, $.300