Library of Congress Cataloging in Publication Data 

Engel, Arnold. 

Tuberculin skin test reaction among adults 25-74 years, United States, 1971-1972. 

(Vital and health statistics: Series 11, Data from the National Health Survey; no. 204) 

(DHEW publication; no. (HRA) 77-1649) 

Includes bibliographical references. 

1. Tuberculin test-United States-Statistics. 2. Health surveys-United States. I. 

Roberts, Jean, joint author. II. Title. III. S’eries: 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. 204. IV. Series: United States. Dept. of Health, 

Education, and Welfare. DHEW publication; no. (HRA) 77-1649. 

RA407.3.A347 no. 204 [ RA644.T7] 312’.0973s 

ISBN 0-8406-0086-O [614.5’42’0973] 77-608065 
Data from the 

NATIONAL HEALTH SURVEY 

Tuberculin Skin Test Reaction 

Among Adults 25-74 Years 

United States, 1971-72 

The prevalence of positive reaction to tuberculin skin tests, indicating exposure to and continuing hypersensitivity to tubercle bacilli, 

in the noninstitutionalized U.S. adult population, shown by age, 

sex, race, geographic region, family income, education, marital status, and a measure of crowding in the household. 

DHEW Publication No. (HRA) 77-1649 

Series 11 

Number 204 

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

Public Health Service 

Health Resources Administration 

National Center for Health Statistics 

Hyattsville, Md. July 1977 
NATIONAL CENTER FOR HEALTH STATISTICS 

DOROTHY P,, RICE, Director 

ROBERT A. ISRAEL, Deputy Director 

JACOB J. FELDMAN, Ph.D., Associate Directorfor Analysis 

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

ELIJAH L. WHITE, Associate Director for Data Systems 

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

ROBERT C. HUBER, Associate Director for Management 

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

PETER L. HURLEY, Associate Directorfir Operations 

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

PAUL E. LEAVERTON, Ph.D., Associate Directorfor Research 

A&ICE HAYWOOD, Information Officer 

DIVISION OF HEALTH E:XAMINATlON STATISTICS 

ARTHUR J. MCDOWELL, Director 

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

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

JEAN ROBERTS, Chie,( Medical Statistics Branch 

ROBERT S. MURPHY, Chief, Survey Pkwming and Development Branch 

ARNOLD ENGEL, M.D., Medical Adviser 

COOPERATION OF THE BUREAU OF THE CENSUS 

In accordance with specifications established by the National Health Survey, the Bureau of 

the Census, under a contractual agreement, participated in the design and selection of the 

sample, and carried out the first stage of the field interviewing and certain parts of the statistical processing for the Health Examination Survey. 

Vital and Health Statistics-Series 11 -No. 204 

DHEW Publication No. (HRA) 77-1649 

Library ofcongress Catalog Card Number 77-608065 
CONTENTS 

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

Testing Procedure ....................................................................................................................................... 3 

Classification of Results .......................................................................................................................... 4 

Findings ....................................................................................................................................................... 5 

Demographic .......................................................................................................................................... 7 

Marital Status ......................................................................................................................................... 9 

Sic of Residence ................................................................................................................................... 9 

Discussion ..................................................................................................................................................... 10 

summary ...................................................................................................................................

12 

References .................................................................................................................................................... 14 

List of Detailed Tables ” .............................................................................................................................. 16 

Appendixes 

L Statistical Notes ................................................................................................................................ 33 

IL Demographic and Socioeconomic Terms. ........................................................................................... 37 

LIST OF FIGURES 

1. Prevalence of tuberculin positive skin tests among adults, by age and sex: United States, 1971-72 . . . . . . . . 6 

2. Ratio of actual to expected prevalence of positive skin tests among adults 25-74 years, by race and sex: 

United States, 1971-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 

3. Ratio of actual to expected prevalence of positive shin tests among adults 25-74 years, by geographic 

region and sex: United States, 1971-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 

4. Prevalence of tuberculin positive shin tests among adults, by annual family income, age, and sex: 

United States, 1971-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 

5. Prevalence of tuberculin positive skin tests among adults 25-74 years, by number of rooms in residence: United States, 1971-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 

LIST OF TEXT TABLES 

k Proportion of adult examinees found tuberculin positive by 4 nurse observers in the Health and Nut& 

tion Examination Survey, 1971-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..~ 4 

B. Percent distributions of specific tests results or history for adults 25-74 years, classified as tuberculin 

positive and tuberculin negative, by sex: United States, 1971-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 

iii 
SYMIBOLS 

Data not available __-_-_--_-._-__-_--__ ---------- -_-_ - - _ - 

Category not applicable -.-__ --_-__- ____ - _-__ -_-_- . . . 

Quantity zero ________________. _ ______ - ________________ -___ _ 

Quantity more than 0 but less than 0.05~--- 0.0 

Figure does not meet standards of 

reliability or precision-- __________________ - ____ * 

iv 
TUBERCULIN SKIN TEST REACTION 

AMONG ADULTS 25-74 YEARS 

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

INTRODUCTION 

In this report basic data on the prevalence of 

positive reaction to tuberculin skin tests indicating exposure to and continuing hypersensitivity to tubercle bacilli are presented by age, 

sex, race, and various other demographic characteristics for U.S. noninstitutionalized adults 

25-74 years of age. The data in this report were 

obtained on a subsample of the first Health and 

Nutrition Examination Survey during the years 

1971-72. 

The Health Examnilln:ion Survey is one of the 

major programs of the Nsrional Center for Health 

Staristics authorized under the National Health 

Survey Act of 1956 by the 84th Congress as a 

continuing Public Health Service activity to determine the health status of the population. 

The data systems programs used to carry out 

the intent of the National Health Survey r include: 

the Health Examination Survey; the Health Interview Survey which collects health information 

from samples of people by household interviews 

focused primarily on the impact of illness and 

disability within various population groups; the 

Health Manpower and Facilities surveys which 

obtain data on hospitals, nursing homes, and other 

resident institutions; and the Health Resources 

Utilization surveys which obtain information on 

persons using and the extent of use of health facilities and manpower. 

The Health Examination Survey is the only 

one of these programs designed to collect needed health statistics information obtainable only 

through direct examinations of probability samples of the population. From direct examinations, 

tests, and measurements data are obtained in 

this program on the prevalence of medically defined illness-known and previously unknown or 

undiagnosed conditions-and on the distributions 

of a variety of health related physical, physiological, and psychological measurements from 

which normative data and appropriate cutting 

points for what is abnormal can be determined. 

Medical history, demographic, and socioeconomic 

data on the sample population under study are 

also collected so that the examination findings 

may be related to them. 

Since 1960 the Health Examination Survey 

has been planned and carried out as a series of 

separate, consecutive programs called “cycles,” 

each of which is limited to some specific segment 

of the U.S. population and to specific aspects of 

health. During the first cycle in 1960-62 the 

prevalence of certain chronic diseases and the 

distribution of various physical and physiological measures were determined among a defined 

adult population. 2v3 For that program a national 

probability sample of 7,710 persons, of whom 

6,672 or 86.5 percent were examined, were selected to represent the 111 million civilian noninstitutionalized adults 18-79 years of age in the 

U.S. population at that time. 

The target populations for the second and 

third cycles in 1963-65 and 1966-70 were, respectively, the Nation’s noninstitutionalized children 6-11 years and youths 12-17 years. 4,5 In 

both the examination was focused primarily on 

health factors related to growth and development. 

For the second program, the size of the probability sample selected to represent the nearly 

24 million noninstitutionalized U.S. children 6-11 

1 
years of age was 7,417 of which 7,119 or 96 percent were examined. In the youths’ program, the 

national probability sample size was 7,518, with 

6,768 or 90 percent examined, to represent the 

22.7 million 12-17 years of age in the civilian 

noninstitutionalized population. 

The first Health and Nutrition Examination 

Survey (HANES-I), from which the findings in 

this report were derived, was designed to measure the nutritional status of the U.S. population 

age l-74 years, to obtain some limited information on general health status of the entire age 

grow, and further information on the health 

status--with particular concentration on cardiovascular, respiratory, and arthritic conditions-- 

and medical care needs of adults 25-74 years of 

age in the civilian noninstitutionalized population. 

A detailed description of the specific content and 

plan of operation including sample design has 

been published.’ 

As in previous Health Examination Surveys, 

the U.S. Bureau of the Census cooperated in the 

sample design and in the initial visits and interviewing at the selected eligible households in 

the 65 primary sampling units throughout the 

United States. Additional house hold visiting, interviewing, history taking, and explaining the 

examination portion of the program were done by 

Health Examination Survey representatives from 

the mobile examination center, The selected sample persons for whom an appointment could be 

made were brought into the specially constructed 

mobile examination centers which were moved 

into a central location in each of the primary 

sampling units. The survey teams which traveled 

to the various survey locations throughout the 

country included professional and paraprofessional medical and dental examiners along with 

technicians, interviewers, and other staff. 

The probability sample design used in the 

study provided for oversampling, at predetermined rates, among the poor, preschool children, 

women of childbearing ages, and the elderly so 

that the nutritional status of these “high-risk” 

groups could be more accurately estimated. It 

further provided for a nationally representative 

subset of 35 of the initially planned primary sampling units throughout the United States SO that 

some preliminary national findings on the nutritional status of the population could be published 

before the total HANES-I survey was completed 

and so that national estimates could be obtained 

from those parts of the examination that were 

included only in the 35-stand subsample. 

Each adult ages 25-74 years selected in the 

sample for the more detailed examination was 

given a tuberculin skin test as part of the examination component relating to respiratory conditions. However, this test, which was administered by the survey staff nurse during the examination, had to be read by the nurseor another 

specially trained staff member between 48 and72 

hours later preferably at the examining center in 

order to save staff personnel time. Because of the 

burden imposed on the examinee by the necessity 

of a second visit, this test was discontinued after 

35 stands. While not on as large a sample base 

as originally planned, these data provide the first 

available national estimates of the prevalence of 

tuberculin positive skin test reactions among the 

civilian noninstitutionalized adults 25-74 years 

of age in the United States. 

For the 35 locations at which the tuberculin 

skin tests were given in HANES-I during the 

period between April 1971 and October 1972, a 

national probability sample of 2,798 adults ,ivas 

selected to represent the 103 million in the target population age 25-74 years. The 1,892 adults 

who came in for examination represent 68.7 percent of the sample adults selected when adjustments are made for the differential sampling 

rates for the age-sex-income defined population 

subgroups. (The unadjusted overall response rate 

for this adult subsample was 67.6 percent.). 

Surveys of the National Center for Health Statistics, including all earlier programs of the 

Health Examination Surveys, have achieved higher 

levels of response than that reached for the 35- 

stand subsample in this first HANES. The 65.7 

percent response rate, while higher than many 

smaller scale population health examination surveys, fails to meet fully the requirements of the 

original probability design. However, following a 

policy of remuneration of participants adopted 

after the completion of 20 PSU’s, there has been 

a significant increase in participation.7 

National estimates in this report are based 

on weighted observations, i.e., the data obtained 

for each examined adult are inflated to the level 

of the total target population. The estimates have 

2 
been calculated as though the examined adults in 

each of the age, sex, and income classes are a 

random subsample of the sample adults in the 

same class (appendix I). While there is evidence 

from the earlier examination surveys and medical 

history data from HANBS that this is a reasonable 

approximation, it is clear that some estimates 

are subject to considerable risk of bias when 

more than one-quarter of the sample persons 

in a particular age-sex-income class were not 

examined. 

While all 1,892 adult examinees 25-74 years 

of age in this detailed HANES subsample were to 

be given the tuberculin skin test, it was administered to 1,580 or 83.5 percent of those examined 

and readings on the degree of reaction were obtained for 1,494 or 79.0 percent oftheexaminees. 

Because of the small sample from which these 

tuberculin skin test results are available, the 

national prevalence estimates cannot be shown 

in as much relevant demographic, socioeconomic, or other detail as desired since the sampling variability is greater and hence the estimates 

less precise than those national estimates usually 

published in these findings reports from the Health 

Examination Survey data. 

TESTING 

PROCEDURE 

At each of the 35 preselected locations 

throughout the country, arrangements were made 

for sample persons to come or be brought into 

the specially designed mobile center for esamination in the morning, afternoon, or evening. 

In the tuberculin skin testing part of the examination the dual procedure of both a standard 

for the mammalian-type purified protein derivative (PPD-S) tuberculin antigen (prepared from 

Mycobacterium tuberculosis) and the only standardized purified protein derivative antigen available prepared from a Battey type of atypical (nontuberculous) mycobacteria (PPD-B) were used. 

The simultaneous skin testing with the PPD-S 

tuberculin antigen and PPD-B antigen permitted 

differentiation between reactivity caused by infection with M. tuberculosis and the other mycobacteria. 

The survey staff nurse, after thorough 

cleansing of the upper one-third of both volar 

forearms with alcohol and holding the forearm 

skin taut, injected intradermally 5 tuberculin 

units (TU) of PPD-S contained in 0.1 cc solution 

approximately 2 inches below the antecubital 

form on the volar surface of the left arm of each 

adult examinee. Similarly an injection of 5 units 

(I-J) of PPD-B in 0.1 cc solution was given in the 

right arm. Both antigens used in the survey examinations were obtained from the Tuberculosis 

Program of the Center for Disease Control (CDC), 

Public Health Service. Dr. Lydia Edwards and 

others of the CDC staff also advised on the dosage 

and methods used in this part of the examination. 

The tuberculin skin test was read 48-72 hours 

after injection. The extent of induration was the 

sole criterion for determining reactivity to the 

two antigens; erythema was ignored. The indurated 

area was measured precisely to the nearest millimeter at its widest transverse diameter after 

thorough palpation and close visual inspection. 

The survey staff nurses giving the injections 

and reading the reactions to the tests were trained 

for approximately 1 week by the experienced staff 

of the Tuberculin Program of CDC. Nurses administered all tuberculin skin tests in the examination and read 92.2 percent ofthem. Of the remainder 5.3 percent were read by other examining 

personnel who had also been carefully trained to 

do this and 2.3 percent by others, almost all (2.1 

percent) of whom were other physicians not specifically trained in the survey method. 

A number of investigators have drawn attention to differences in tuberculin skin test 

results due to variability in methods or observers.8.iOThesevariations may arise from differences in the amount of test material injected, 

the site of the injection, whether the test material leaks out, and the precision used by the reader 

in interpreting the reaction. In HANES-I these 

identifiable sources of variability were controlled as much as possible through training 

in the use of the standard methods but no actual 

program >f replicate readings was attempted. 

However, comparison of the percent of adults 

found to be tuberculin positive by the four nurses 

who did most of the readings (about 80 percent) 

show remarkably little variation among them 

(table A). 

3 
Table A. Proportion of adult examinees 

found tuberculin positive by 4 nurse 

observers in the Health and Nutrition 

Examination Survey, 1971- 72 

Nurse 

observers 

Number Percent 

of of 

examinees examinees 

observed tuberculin 

positive 

1 --------------- 399 22.3 

Each of the nurses was assigned to examination locations in different parts of the country. 

Hence some of the differences in these rates 

among the nurse observers may reflect area 

differences in tuberculin sensitivity. 

of those tested and read, 99.1 percent were 

read within 2-3 days after administration. The 

remaining 0.9 percent were read on the 4th day 

after administration. Tests were read in the home 

for 10.4 percent, at work for 2.7 percent, at the 

mobile examination center for 83.8 percent, and 

at some other location for 3.1 percent. 

In all, tuberculin skin tests were administered and read for 78.5 percent of theexaminees. 

There were 6.6 percent not given the test because 

their examination was done a day or two before 

the mobile examining unit was scheduled to move 

to the next location and survey personnel would 

not have been available to read the reaction. In 

addition 1.0 percent refused the test, giving as 

their reason a history of tuberculosis or INH 

prophylaxis, 0.7 percent because of a history of 

a previous positive test, and 0.7 percent because 

of a history of a recent negative test. The remaining 12.5 percent included 7.4 percent who 

were not administered the test because the examinee was unable or refused to return and 5.1 

percent to whom the test was given but who did 

not return for a reading. 

Classification of Results 

The following classification of the tuberculin 

skin test reactions or history were used in this 

report: 

Tubwculin positive 

1. All examinees with reactions toPPD-S 

2. 

3. 

equal to or greater than 10 mm. in 

diameter. 

All examinees with reaction to PPD-S 

of 5-9 mm. in diameter and with the 

reading of PPD-S at least 2 mm. 

greater than the PPD-B reading. This 

part of the classification is based on 

the findings from a followup study of 

625,000 naval recruits who showed a 

risk of developing tuberculosis similar to those in examinees groups 1 

and 2.11 

All examinees not given the tuberculin 

skin test because of a history of a 

positive reaction, tuberculosis, or INH 

prophylaxis. It was assumed that persons in this group would have ,had a 

positive reaction if the test had been 

given them. 

Tuberculin ns&~vs 

1. All those whose PPD-S reading was 

kSS than 5 mm. or with PPD-S of 

5-9 mm. but with the PPD-S less than 

the PPD-B reading plus 2 mm. 

1. Those not given the test because they 

were examined in the last day or two 

at a particular location. 

2. All others to whom the tests were not 

administered or were administered 

but not read. 

More than one-fifth of the examinees were 

classified as tuberculin positive on the basis of 

test results or history. This included 65 percent 

who had a strong reaction to PPD-S of 10 mm. 

or more in diameter, 25 percent who had a less 

marked skin reaction to the tuberculin antigen, 

and the remaining 10 percent who gave a history 

of tuberculosis or previous positive test reaction 

(table B). For the remaining four-fifths Iof the 

examinees classified as tuberculin negative, 96 

percent reacted more strongly to the PPD-B 

than to the tuberculin or had a PPD-S less than 

5 mm., 3 percent showed a PPD-S reaction 

5-9 mm. and an $qual reaction to the tuberculin 

and the Battey, and 1 percent gave a histary of’ 

a recent negative test reaction. 

4 
Table B. Percent distributions of specific test results or history for adults 25-74 

years, classified as tuberculin positive and tuberculin negative, by sex: United 

States, 1971-72 

25-74 years 

Test result or history 

Both 

sexes Men Women 

Total tuberculin positive------------------ 

PPD-S 10 nun. or more ------_--------_------------- 

PPD-S 5-9 min. with PPD-S 2 mm. or more----------- 

greater than PPD-B------------------------------ 

Tuberculosis history ---_---------_--------------- 

previous positive reaction----------------------- 

Total tuberculin negative------------------ 

PPD-S 5-9 mm. with PPD-S and PPD-B differing 

by less than 2 mm. _----------------_------------ 

PPD-S 5-9 mm. with PPD-B at least 2 mm. less 

than PPDS; PPD-S less than 5 mm.--------------- previous negative reaction----------------------- 

Percent dis tr ibut ion 

100.0 100.0 100.0 

65.1 71.5 58.1 

25.1 18.5 32.4 

2:; 2:: ?1 

100.0 100.0 100.0 

2.7 3.7 1.9 

96.2 95.8 96.5 

1.1 0.5 1.6 

Those 6.6 percent of the examinees classified as unknown with respect to their reaction to 

the tuberculin antigen who were not given the 

test because their examination was scheduled in 

the last day or two at a particular location are 

unlikely to have biased the findings from this 

study. Among the remainder of those classified 

as unknown with respect to tuberculin reaction 

or history (12.0 percent of all examinees) some 

small potential sources of bias in either direction 

may exist although the bias here is more likely 

to be positive. The proportion returningfor reading was slightly greater among those living in 

large urban areas, where the prevalence of tuberculosis and hence the proportion with positive 

reactions to the tuberculin antigen tends to be 

higher than among those living in smaller urban 

or rural areas who lived further from the examining center. Also contributing to this bias would 

be the expected greater likelihood of positive than 

negative reactors to return for a reading. The 

effect on the likelihood of the tested examinee to 

return for a reading among those who had been 

tested before would be varied depending upon 

their concern and previous experience. However, 

the distribution of income and educational levels 

of those classified as unknown with respect to 

their reaction to tuberculin do not differ significantly from that among those with known reactions. 

All further analyses of these data will be 

limited unless further specifically qualified to the 

total group of tuberculin positive reactors (those 

with reactions to PPD-S of 10 mm. or more, 

those with PPD-S of 5-9 mm. and PPD-S less 

PPD-B of -1-2 mm. or more, and those who were 

not tested but who had a history of tuberculosis 

or previous positive tuberculin reaction). It is 

assumed that the prevalence of the tuberculin 

positive among those individuals designated as 

unknown would be roughly similar to that for 

those whose test results were available in this 

study across all demographic and socioeconomic 

variables considered (appendix II). 

FINDINGS 

The prevalence of positive reaction to tuberculin skin tests among the civilian noninstitutionalized adults age 25-74 years in the United States 

5 
is 21.5 percent, as estimated from findings ofthe 

national probability sample examined in the Health 

and Nutrition Examination Survey of 1971-72. If 

those with sensitivity to tuberculin (PPD-S) of 

less than 10 mm. are excluded, the prevalence 

of this degree of tuberculin positive reaction 

among this age group is 16.1 percent (table 1). 

Men are more likely than women to be tuberculin positive. The prevalence for all tuberculin 

positive is 24.2 percent among men and 19.1 percent among women. Omitting the reactions to 

PPD-S of less than 10 mm,, the prevalence for 

this degree of reaction is 19.7 percent among 

men and 12.9 percent among women. 

In both men and women the prevalence of 

positive reaction rises steadily from 12.5 percent 

and 10.6 percent, respectively, in the youngest age 

group 25-34 to 30.1 percent and 27.3 percent, respectively, in the 45-54 age group (figure 1). 

In the age group 55-64 the prevalence of positive 

tests declines slightly for both sexes? ‘It continues to decline in women through the last age 

group (65-74) but there is a sharp rise among the 

oldest group for men. The rise appears to be 

statistically significant but due to sampling vari01 ’ I I I I 

30 40 50 60 70 

AGE IN YEARS 

Figure 1. Prevalence of tuberculin positive skin tests among 

adults, by age and sex: United States, 1971-72. 

ation may not reflect so large a rise in prevalence in the actual population which it represents. 

There is in general a paucity of comparable 

data on age trends in tuberculin reaction in the 

adult population. However, a community study in 

Muscogee County, Georgia and Russel County, 

Alabama in 1950 using 5 TU of PPD showed in 

general an age trend quite similar to that of the 

HANES findings.” In the Muscogee County study 

and three other community-wide studies in Palmier County, North Carolina; Falls County, 

Minnesota; and Plainsville, Montana the prevalence of TB positive reaction was higher for 

males than females.13 

The age distribution of TB positive reaction 

is undoubtedly the resultant of a number of factors. High rates of TB infection have been reported in older adult groups of the population in 

various early tuberculin skin test and autopsy 

studies. In one of these studies, autopsies of 

more than 1,000 New York City residents who 

died suddenly and unexpectedly during the years 

1944-47 revealed evidence of previous TI3 infection in 88 percent of those 60 years and 

older, i4 and 80 percent of those between 40 and 

50 years of age. In a 1934 study of University of 

Maryland Medical School freshman 65.4 percent 

were positive to 1 TU but by 1957 only 10.6 percent were positive to 1 TU. Opie in 1927 found 

70.4 percent of Philadelphia school children 

positive to 10 TU. I5 During the years 1949-64, 

a very large continuing study of naval recruits 

demonstrated a decrease in percentage of positive reactions of about % of 1 percent per year.13 

Lower prevalence rates found in younger individuals are undoubtedly the result of the much 

lower risk of exposure to and hence decreased 

probability of infection with tuberculosis in recent years. Testing programs for 2,334,960 first 

grade children in 1968-69 revealed the very low 

rate of only 0.37 percent tuberculin positive.r’ 

Two other factors may serve to reduce the 

prevalence rate in the oldest age groups. A followup study of a cohort of 1,324 children in Ontario, 

tested at two points in time 36 years apart demonstrated a decrease in prevalence of a positive reaction to 5 TU in the same children from 52 percent to 42 percent. It appears likely that new 

infection and reinfection may be needed to maintain the tuberculin hypersensitive reaction. l6 

6 
Another factor may be a diminished reactivity 

of the skin in old age. Woodruff found in new admissions to a tuberculosis hospital a reaction 

rate to 1 TU of old tuberculin (OT) in elderly 

patients only 77 percent of that in patients of all 

ages.17 

Because the sampling variability of age-sex 

specific values for each demographic subgroup is 

large in this study, a summary comparison was 

considered preferable to the presentation of prevalence rates specific by age and sex in the following sections of this report. For this reason, the 

actual prevalence rate for each group is compared 

with an expected rate. The expected value of a 

particular group is obtained by weighting age and 

sex specific rates for the total United States by 

the number in the corresponding age-sex classes 

for that group. This will eliminate from the expected rate the effect of differences due solely 

to those from age-sex distributions in the various 

groups of the population. A positive difference 

between actual and expected rates, for example, 

indicates that the prevalence rate for the group 

is higher than expected though such differences 

may arise by chance (or through sampling variability). Alternatively the data can be presented 

as a ratio of actual to expected rates. If the rate 

is greater than 1.0, the actual rate is higher 

than expected. If the rate is less than 1.0 the 

actual rate is less than expected. 

Demographic 

Rnx.- Prevalence rates for tuberculin positive reaction are greater among Negro than white 

adults for both men and women, although the difference is only statistically significant for men 

(table 2 and figure 2). This finding is consistent 

with those from the testing of naval recruits 

during the years 1958-69. During those years 

3.8 percent of white and 12.4 percent of Negro 

men had positive tuberculin reactions measuring 

10 or more millimeters in diameter>* Data from 

the Muscogee County Study previously ,cited l2 

also demonstrates a considerably higher prevalence of tuberculin positive in the Negro population of this county. 

Are&--Regional differences in the prevalence of tuberculin positive reaction are not 

particularly striking. Prevalence rates are lower 

MEN WOMEN 

2.0 r 

0.0 

White White 

Figure 2. Ratio of actual to expected prevalence of positive skin 

tests among adults 25-74 years, by race and sex: United 

States, 1971-72. 

among women in the South than those in the other 

regions. While the prevalence is higher among 

both men and women in the Northeast than elsewhere the differences are not large enough to be 

considered statistically significant (table 3 and 

figure 3). 

I MEN WOMEN 

North- Mid. 

rr(m( 

NMh- Mid- South Weat 

-w 

Figure 3. Ratio of actual to expected prevalence of positive skin 

tests among adults 25-74 years, by geographic region and sex: 

United States, 1971-72. 
There appeared to be some tendency towards 

higher prevalence of tuberculin positive reaction 

in central city areas than elsewhere among both 

men and women but only the total prevalence for 

all adults in this type of location is sufficiently 

higher to be statistically significant (table 4). 

Adults living in urbanized areas with populations 

of 3 million or more and of X-1 million have a 

somewhat higher than expected prevalence of 

tuberculin positive; the converse is true of adults 

living in rural areas, but neither of these relationships is statistically significant (table 5). A 

similar pattern of prevalence was found in the 

U.S. Naval Recruit Study i2 which showed a prevalence of 4.2 percent in metropolitan areas, 2.8 

percent in farm areas, and 3.6 percent in other 

areas. In some areas in the Naval Recruit Study 

such as Minneapolis-St. Paul rates were similar 

for the various counties included in the area. For 

other areas such as Boston, New York, Philadelphia, and San Francisco rates were higher in 

the densely populated counties. This of course 

may reflect the differences in the racial and 

socioeconomic composition of the population 

among the different cities in the U.S. 

The present national study also shows anextremely low prevalence rate of tuberculin positive among women living in farm compared to 

those living in nonfarm residences (table 6). This 

-group might be expected to have less exposure to 

active tuberculosis than other groups in the population. 

Inciwne.-- In order to delineate the tuberculin 

positive prevalence by income more fully, the 

summary approach was not used. A careful examination of individual age groups (table 7 and 

figure 4) reveals a markedly lower prevalence 

among those individuals with annual family inMEN WOMEN 

AGE IN YEARS 

Figure 4. Prevalence of tuberculin positive skin tests among adults, by annual family income, age, and sex: United States, 1971-72. 

8 
come of $10,000 and more in the younger age 

group under 35 years. This relative low prevalence among those in the high income level 

families in the younger groups becomes much 

less marked with increase in age and indeed in 

the two oldest groups in women and the oldest 

group in men this relation to income appears to 

reverse in direction. This may reflect conditions 

in the recent past where family income has had 

a strong influence on the opportunity of becoming 

tuberculin positive and in the more remote past 

where income may not have had as much as effect 

on the chances of becoming tuberculin positive. 

Changes in ‘residence and income over a life time 

are among the many factors that make an interpretation of these data difficult. It should be noted 

that in one careful study of household contacts 

to index cases 19 susceptibility to infection in 

households containing an index case of tuberculosis was found not to be significantly influenced by sex, age, or socioeconomic factors. 

For example, 71.4 percent of the white and 70.2 

percent of the Negro household members became 

infected when exposed to a sputum positive index 

case, while only 37.0 percent of the white and 

37.1 percent of the Negro became infected when 

exposed to a sputum negative case. Of course the 

chances of exposure and the degree of exposure 

to active cases of tuberculosis would be expected 

to vary greatly in different groups of the population of the U.S. at present. Such factors as the 

marked decrease in infectiveness following institution of adequate chemotherapy should also 

be considered.12 

In the present study the association oftuberculin positive reaction with education is similar 

to that shown with income (table 8). There is a 

lower prevalence of tuberculin positive among 

men with the highest level of education than 

others. A slightly lower than expected prevalence 

rate for this highest education group is also 

found among women. The differences are not 

large enough to be statistically significant. 

There does not appear to be any significant 

differences in these prevalence rates in regard 

to usual activity for either men or women (table 

9). Nor is there any particular pattern of differences in prevalence rates among those working 

in different industries (table 10). None of the 

differences in prevalence for occupational groups 

are statistically significant though in general the 

pattern of differences found is what might be expected on the basis of income and education. 

For example, lower rates are shown for professional and technical groups than others (table 11). 

The data are also somewhat similar to mortality 

data based on a U.S. 1960 Census sample, especially in regard to reduced rates for professional 

workers and increased rates forlaborers.13Mortality rates are influenfed of course by factors 

such as susceptibility to developing clinical 

disease following infection and the intervention 

of medical treatment. 

Marital Status 

There appears to be some tendency toward 

higher than expected prevalence of tuberculin 

positive in divorced or separated men andwomen 

(table 12). However, the elevation is not large 

enough to be significant considering the relatively small numbers in these two groups. It is 

interesting to note that in the tuberculosis cases 

reported in Denmark from 1960-68, the prevalence 

rates among divorced men and women were considerably higher than among married men and 

women.20 

Size of Residence 

There is a definite trend toward decreasing 

prevalence rates of positive tuberculin reaction 

among adults as the number of rooms in their 

residences increases (table 13 and figure 5). The 

trend is monotonic from one to five rooms with 

some considerable fluctuation following further 

increase in the number of rooms in the examinee’s 

residence. More specific data on the degree of 

crowding or space available per household occupant were not computed. 

Crowding has long been considered to be one 

factor involved in the transmittal of tuberculosis 

infection operating probably through decreased 

atmospheric dilution of the infectious agent. 

In a study of intrafamilial transmission of 

tuberculosis, i.e., household infection by an index case residing in that household, crowding 

correlated .22 with acquisition of infection.21 Of 

course, in common with other factors considered, 

the degree of crowding present at the timzof this 

9 
1.8 

E 1.4 

L 

L E 1.2 

e 

i 

1.0 

6 0.8 

< 

8 0 0.6 

0.4 

0.2 

l-l” -.- 

1 2 3 4 5 6 7 8 9 or 

nwrc 

NUMBER OF ROOMS 

Figure 5. Prevalence of tuberculin positive skin tests among 

adults 25-74 years, by number of rooms in residence: 

United States, 1971-72. 

examjnation may not represent the degree of 

crowding in an individual’s history at the time 

in the past during which he might have been at 

greatest risk of being infected with tuberculosis. 

Since the extent of crowding within households is 

also positively correlated with family income, 

some of the association of the degree of positive 

tuberculin reaction with crowding shown here may 

be due to the previously noted association with 

family income. 

DISCUSSION 

Tuberculin hypersensitivity is a specifically 

acquired capacity of lymphoid cells to interact 

with tubercule bacilliary antigens, The delayed 

or cellular type of hypersensitivity is a reaction 

to the protein antigens and perhaps to other constituents of the tubercule bacilli. 22 Purified 

protein derivitive of M. tuberculosis as prepared 

by Seibert (PPD-S) has been analyzed and found 

to be a proteinaceous preparation containing 1.2 

percent nucleic acid and 5.9 percent polysaccharide.23,Purified preparations of tuberculins are 

more likely to identify tuberculosis than their 

source material, Old Tuberculin, which has been 

aptly called a witch’s brew. l2 However, even 

standardized and purified tuberculosis such as 

PPD-S (United States) and PPD-RT23 (World 

Health Organization) may in practice give results 

which differ from each other.24 

Hypersensitivity to tuberculosis, once acquired, is persistently reactive throughout life 

in most people, This presumably occurs because 

the individual retains a focus of dormant bacilli 

and is occasionally exposed to freshly acquired 

tubercle bacilli. 22 The degreeof sensitivity may 

not remain the same from I. year to the next. but 

may vary gradually in either direction or mag- . 

nitude. 25 A number of conditions such as influenza, infectious mononucleosis, scarlatina, 

sarcoidosis, amyloidosis, Hodgkins disease, leukemia, measles, prolonged steroid therapy, and 

terminal tuberculosis may either temporarily 

or permanently remove an individual’s established 

tuberculin sensitivity.22 Tuberculin sensitivity 

may also be acquired through BCG vaccination. 

However, in this country relatively few persons 

would have been sensitized in this way. Aside 

from its use in field trials, BCG vaccination 

in the United States has been limited to special 

groups-nurses, medical students, laboratory 

workers, and others presumed to be at considerable risk of developing tuberculosis because of 

their environment. BCG has not been used extensively even among those special-risk groups.26 

The purpose of a dual test as used inthe 

HANES survey is to distinguish between sensitivity to the bacillus M. tuberculosis from sensitivity to other generically related bacilli.27 The 

control employed was a purified protein derivative 

of an atypical bacillus of the Battey strain (PPDB). This strain is antigentically related to M. 

tuberculosis and gives cross-reactions to it that 

will be less strong than to M. tuberculosis among 

individuals who have acquired sensitivity to the 

latter organism. The validity of this dual test 

has been determined in a followup study of 

625,000 U.S. naval recruits with the following 

results obtained: (1) PPD-S 12 mm. or greatertuberculin positive rate of 330 per 100,000; (2) 

PPD-S 6-11 mm. and greater in diameter than 

PPD-Battey by 2 or more mm.-tuberculin positive rate of 298 per LOO,OOO; (3) PPD-S 6-11 

mm. and either equal in diameter or +l mm. to 

PPD-Battey-tuberculin positive rate of 95 per 

10 
100,000; (4) PPD-S 6-11 mm. and smaller than 

PPD-Battey by at least 2 mm.-tuberculin positive rate of 17 per 100,OOO.rl 

Exposure to an individual who has tuberculosis in a household is not a guarantee that others 

in the same household will become infected with 

TB. For example, only 51 percent of children 

5- 19 living in households of sputum positive cases 

in rural Tennessee in the 1930’s were infected by 

the time the source case was diagnosed.28 The 

likelihood of contracting an infection from an 

active case in the household depends on such 

factors as the severity of the disease, crowding, 

intimacy of exposure, and the mode of family 

living.21 Factors affecting an individual’s resistance to disease will also determine whether 

an infection develops into a clinical condition. 

For example, in the study among naval recruits 

tuberculosis morbidity was found to increase with 

height and to be reduced by weight even though 

physique was not associated with any difference 

in the infection rate as determined by tuberculin testing.r2 

Improvement of host resistance accompanying rising standard of living has been credited 

with some of the reduction in TB morbidity which 

occurred prior to the more rapid decrease after 

chemotherapy introduction in 1947. Widespread 

malnutrition among the population of occupied 

Holland in the last year of World War II was 

accompanied by a substantial increase in tuberculosis. 24 

Mortality from tuberculosis in the United 

States showed a dramatic decrease during the 

20th century. In 1900 the mortality rate was 202 

per 100,000 population. By 1968 the rate had 

fallen to 3.3 per 100,000.29 However, as in other 

countries, it is likely that the overall decline in 

infection for all ages in the U.S. population does 

not parallel that of the TB mortality or morbidity 

but is much lower.30 

The reservoir of infected individuals is of 

interest because after successful recovery from a 

primary infection the body is unable to completely rid itself of invading organisms leaving 

an unknown but significant proportion of those 

individuals at risk of reactivation of the TB infection throughout the rest of their lives.i2 One 

study of bacteriologically confirmed cases found 

evidence of tuberculous lesions among 72 percent 

on available preexisting X-rays. These individuals 

were experiencing their first clinical episode of 

disease. The lesions encountered were apical 

abnormalities. 

Only 5 percent of the individuals studiedover 

50 years of age were able to give a history of close 

contact with an active case of TB in the preceding 

3 yearse31 By 1970, 55 percent of the new 

cases in the United States occurred among adults 

over the age of 45. Hence it was estimated in 

1971 that at that time the predominant source of 

new TB cases in the U.S. was endogenous breakdown of already infected individuals. Some of 

the factors that have been implicated in or associated with reactivation are old age, alcoholism, 

steroid therapy, diabetes, and silicosis. 31 

With the declining incidence of the disease 

in the United States and the correspondingly low 

level of transmission of infection, new c;;es are 

increasingly restricted to older persons. Further evidence of this change in the morbidity 

rate is available from a study in Minnesota showing 

an increase in the proportion of new TB cases 

among those 45 years and older from 16 percent 

in 1920 to 66 percent in 1968 in that State. This 

was accompanied by a rise in the proportion of 

TB deaths in Minnesota among adults over 45. 

This age group accounted for 23 percent of the 

TB deaths in that State in 1920 and 96 percent in 

1968. In general, the estimates for the tuberculin 

positive U.S. adults from HANES reveal thesame 

differentials in prevalence in regard to sex, race, 

income, and #other demographic and socioeconomic 

indicators as in many of the epidemiological 

studies reported in the literature. From the 

HANES data it would appear that socioeconomic 

factors, as represented by income, show at present 

a much stronger relationship with the prevalence 

of TB infection than they did in the 1st third of 

the 20th century. The HANES data also reveals 

that a considerable proportion (21.5 percent) of 

the adult population of the U.S. is infected with 

tuberculosis (tuberculin positive) and is therefore at risk of reactivation. 

This prevalence estimate of 21.5 percent of 

the tuberculin positive reactors among the adult 

U.S. population age 25-74 years is, of course, 

subject to sampling variability since it was based 

on the findings among a small national probability 

sample, as described. The 95-percent confidence 

11 
limits for this estimate are between 17.9and25.1 

percent. In other words, the actual prevalence rate 

for the tuberculin positive in the U.S. adult population may be as high as 25.1 percent or as low 

as 17.9 percent but is not likely to be higher or 

lower than these values. 

Increasingly, the goals of public health have 

shifted from only controlling a disease towards 

its eventual eradication. The year 1976 marked 

the apparent final eradication of smallpox. Tuberculosis, which killed Keats and Thoreau and 

marked the end of innumerable operatic prima 

donnas, is no longer the plague it used to be. As 

tuberculosis has diminished in prevalence public 

concern has shifted to other diseases. However, 

tuberculosis eradication is not a simple matter. 

These HANES data would indicate that there are 

still very large infected reservoirs of the disease 

in the population and no completely effective 

vaccine is available to protect the uninfected. 

The tuberculin testing component used in the 

HANES survey 197 l-72 in spite of its shortcomings 

with respect to sample size and possible nonresponse bias would appear to provide a prototype 

of a monitoring mechanism for evaluating the 

effectiveness of the national tuberculosis control 

in this country. Of course it cannot do more than 

act as a supplement to State and local tuberculosis 

control programs. These serve to pin point areas 

with high TB morbidity such as Central Harlem 

in New York City. Future national tuberculin 

surveys would need to include the pediatric as 

well as adult age groups. The sample size should 

also be greatly increased. 

In conclusion, while the prevalence of tuberculosis is greatly diminished from what it was 

40 years ago it is still a major health problem 

with a sizeable reservoir of infected individuals 

in the population. Disease in those individuals 

may reactivate at any time and can serve as a 

source of new infection. Continued progress in 

TB control depends on continuous efforts that will 

have to be maintained for many years to come. 

SUMMARY 

This report contains national estimates of the 

prevalence of tuberculin positive reaction among 

the civilian noninstitutionalized adults 25-74 years 

of age in the United States, based on the findings 

from the tuberculin testing component in the 

Health and Nutrition Examination Survey of 1971- 

1972. These prevalence rates are analyzed by 

age, sex, race, geographic region, and relevant 

socioeconomic factors. 

Major findings from this study incllude: 

0 In the United States an estimated21Spercent of noninstitutionalized adults 25-74 

years are tuberculin positive. Men are 

more likely than women to be tuberculin 

positive, the prevalence rates being 24.2 

percent and 19.1 percent, respectively. 

0 Prevalence of positive tuberculin reaction 

in both sexes increases with age from 

from 25 to 54 years but tends to decline 

somewhat after 55 years in women. For 

men, the rate increases again at 65-74 

years. 

l The highest prevalence rates are among 

Negro men. The next highest are those 

for Negro women and they are followed 

by those for white men and white women 

in that order. 

0 Lower prevalence of tuberculin positive 

reaction was found among white women 

in the South and women living on farms 

than others. Adults living in central city 

areas had higher prevalence rates than 

those living elsewhere. 

0 Marked income differentials are evident 

with the lowest tuberculin positive prevalence among young adults under 35 years 

with annual family income of $10,000 or 

more. In older adults, this income differential becomes progressively less with increasing age until by 55 years for women 

and 65 years for men the pattern reverses 

and the highest prevalence is found among 

the highest income group. 

l A significantly lower prevalence of tuberculin positive reaction was found in men 

with some college education than in those 

with lesser education. 

aA trend toward decreased prevalence of 

positive tuberculin reaction among adults 

as the number of rooms in their residences 

increased. 

000 

12 
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1 OLoudon, R. G.; Lawson, R. A. Jr.; and Brown, J.: 

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1 4Hoeprich, P. D.: Infectious Diseases; A Guide to the 

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and Schumacher, M.: Changes in the tuberculin pattern 

in students between 1930 and 1960. Am. Rev. Respir. 

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1 7Woodruff, C. E., and Chapman, P. T.: Tuberculin 

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23Moulton, R. G.; Dietz, T. M.; and Marcus, S.: Isolation of specific and nonspecific components from purified protein derivatives. Am. Rev. Respir. Dis. 

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14 
26Pahner. C. E.; Shaw. 1;. W.; and Comstock, G. W. 

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15 
LIST OF DETAILED TABLES 

1. Prevalence rates and standard errors for tuberculin positive adults 25-74 years, by age and sex: United States, 1971-72........... 

2. Actual and expected prevalence rates and standard errors for tuberculin positive adults 25-74 years, by race and sex: United 

States, 1971-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .................................................. 

3. Actual and expected prevalence rates and standard errors for tuberculin positive adults 25-74 years, by sex and geographic 

region: United States, 1971-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .......................... 

4. Actual and expected prevalence rates and standard errors for tuberculin positive adults 25-74 years, by sex and location of 

place of residence: United States, 1971-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . ...... 

5. Prevalence rates and standard errors for tuberculin positive adults 25-74 years, by sex and population size of place of 

residence: United States, 1971-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...................... 

6. Actual and expected rates and standard errors for tuberculin positive adults 25-74 years, by sex and farm-nonfarm residence: 

United States, 1971-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...................................... 

7. Prevalence rates and standard errors for tuberculin positive adults 25-74 years, by age, sex, and family income: United 

States, 1971-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ................................................... 

8. Actual and expected rates and standard errors for tuberculin positive adults 25-74 years, by sex and education: United 

States, 197 I-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..“....................... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ........................ 

9. Prevalence rates and standard errors for tuberculin positive adults 25-74 years, by sex and usual activity: United States, 

1971-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....... . ..................................................... 

19. Actual and expected rates and standard errors for tuberculin positive adults 25-74 years, by sex and industry: United States, 

1971-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .............................................................. 

11. Actual and expected rates and standard errors for tuberculin positive adults 25-74 years, by sex and occupation: United 

States, 1971-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .................................................. 

12. Actual and expected rates and standard errors for tuberculin positive adults 25-74 years, by sex and marital status: United 

States, 1971-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ................................................ 

13. Actual and expected rates and standard errors for tuberculin positive adults 25-74 years, by number of rooms in place of 

residence: United States, 1971-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .... . ................. 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

28 

30 

31 

16 
Table 1. Prevalence rates and standard errors for tuberculin positive adults 25-74 years, by age 

and sex: United States, 1971-72 

Age and sex 

Tuberculin positive 

Tuberculin positive 

excluding reaction to 

PPD-S of less than 

10 mm. diameter 

Rate per 100 Standard error 1 Rate per 100 1 Standard error 

25-34 

34-44 

45-54 

E44 

Both sexes 25-74 years-------- 21.5 1.78 16.1 1.33 I 

years------------------------- 

years------------------------- 

years------------------------- 

years------------------------- 

years------------------------- 

&fen 25-74 years----------------- 

25-34 years------------------------- 

35-44 years------------------------- 

45-54 years------------------------- 

55-64 years------------------------- 

65-74 years------------------------- 

Women 25-74 years--------------- 

, q p, 

11.4 2.83 7.5 I 1.86 

3.55 13.9 

3.71 22.9 

3.65 18.0 

2.46 19.7 

24.21 2.37 

I 

25-34 10.6 3.86 

35-44 

years------------------------- 

45-54 

years------------------------- 16.9 5.27 

years------------------------- 27.3 4.53 

55-64 years------------------------- 23.7 3.94 

65-74 years------------------------- 17.1 5.57 

10.5 

14.7 

24.4 

22.8 

31.3 

3.57 

2.88 

4.73 

';% . 

1.32 

17 
Table 2. Actual and expected prevalence rates and standard errors for tuberculin positive adults 25-74 years, by race and sex: United States, 1971-72 

Sex, rate, and standard error 

Both sexes 

Actual--------------------------------------------------- 

Expected --------------------------~-------------------- 

Actual/Expected1 _-----------------_-------------------- 

Standard error--------------------..-------------------- 

White 

%i . 

0.91 *1.70 

1.62 *5.50 

Men 

Actual ---_--_---------_-----------~-------------------- 

Expected----------------------------------------------- 

Actual/E~ectedl---------------------------------------- 

Standard error----------------------------------------- 

22.5 *41.7 

24.2 Jr24.4 

0.93 w.71 

2.32 Ji’6.89 

Women 

Actual----------------------------..-------------------- 

Expected ----_---------__-----------.-------------------- 

17.1 

19.2 

Actual/Expectedl------------------..-------------------- 0.89 

Standard error------------------------------------------- 2.03 

lActual/Expected means actual divided by expected. 

Negro 

3135.0 

Jr20.6 

k30.6 

kJ8.l 

*1.69 

*6.60 

18 
Table 3. Actual and expected prevalence rates and standard errors for tuberculin positive adults 25-74 years, by sex and geographic region: United States, 1971-72 

Sex, rate, and standard error 

Both sexes 

Actual ----------------------------------- 

Expected--------------------------------- 

Actual/Expectedl------------------------- 

Standard error--------------------------- 

Northeast Midwest south West 

26.9 

22.0 

1.22 

4.81 

21.6 

21.1 

1.02 

3.51 

18.6 18.2 

21.5 21.2 

0.87 0.86 

4.00 2.53 

Men 

Actual ----------------------------------- 

Expected--------------------------------- 

Actual/Expectedl------------------------- 

Standard error --------------------------- 

30.9 

24.7 

1.25 

4.86 

21.8 

23.8 

0.92 

4.91 

24.7 19.6 

25.0 23.5 

0.99 0.83 

6.62 2.49 

Women 

Actual----------------------------------- 23.9 21.5 13.8 16.9 Expected--------------------------------- 20.0 18.4 18.8 18.9 

Actual/Expectedl---------------.--------- 1.20 1.17 0.73 0.89 Standard error--------------------------- 6.34 2.86 2.38 3.32 

'Actual/Expected means actual divided by expected. 

19 
Table 4. Actual and expected prevalence rates and standard errors for tuberculin positive adults 25-74 years, by sex and location of place of residence: United Statles, 

1971-72 

Sex, rate, and standard error SMSA in SMSA not in 

central city central city 

Location nqt 

in SMSA 

Both sexes 

Actual--------------------------------- 27.8 18.7 18.9 

Expected -"----------------""-----""---- 21.3 21.2 21.8 

Actual/Expectedl------------------------ 1.31 0.88 

Standard error 

0.87 

--------------------_____ 3.12 1.89 3.08 

Actual---------------------------------- 

Expected------------------------------- 

Actual/Expectedl----------------------- 

Standard error------------------------- 

30.8 22.4 21.1 

24.2 23.6 25.0 

1.27 0.95 0.84 

4.16 2.51 4.71 

Women 

Actual--------------------------------- 25.5 Erected------------------------------- 19.1 

15.4 

19.2 

116.9 

1'9.0 

Actual/Expectedl----------------------- 1.34 0.80 0.89 Standard error------------------------- 4.04 2.25 2.65 

lActual/Expected means actual divided by #expected. 

20 
Table 5. Prevalence rates and standard errors for tuberculin positive adults 25-74 years, by sex 

and population size of place of residence: United States, 1971-72 

-I- Population size of place of residence 

Sex, rate, and 

standard error t 

Both sexes 

Actual---------------- 28.0 20.0 *28.0 18.9 Jr24.2 *30.0 21.0 16.2 

Expected-------------- 20.8 21.5 *22.0 21.8 *21.7 *20.6 22.8 21.4 

Actual/Expectedl------ 1.35 0.93 *1.27 0.87 *1.12 Jr1.46 0.92 0.76 

Standard error-------- 4.90 2.05 *10.70 2.04 Jr19.54 *10.40 5.15 3.86 

Actual---------------- 

Expected-------------- 

Actual/Expectedl------ 

Standard error-------- 

32.3 

23.0 

1.40 

7.04 

;3*; . 

0.75 

2.26 

*34.5 22.4 *37.4 *29.6 *22.5 

*25.1 25.0 *24.7 *23.1 *26.9 

*1.37 0.90 *1.51 *1.28 *0.84 

*13.99 1.64 *34.06 *11.29 *7.49 

E*i . 

0.79 

5.91 

Actual---------------- 24.6 22.2 *24.0 16.0 *15.5 *30.3 *19.3 13.7 Expected-------------- 19.1 18.8 x20.0 19.1 *19.8 *18.3 CL8.3 19.0 

Actual/Expected'------ 1.29 1.18 *1.20 0.84 *0.88 *1.66 *1.05 0.72 

Standard error-------- 5.85 3.81 Jr8.78 3.21 *13.14 *12.13 *6.79 2.83 

3,000,000 l-3 250,000- Less than 25,000 10 ) ooo- 2,500- 

or more million 999,999 250,000 or more 24,999 9,999 

Urbanized areas T Outside urbanized areas T 

Rural 

areas 

'Actual/Expected means actual divided by expected. 

21 
Table 6. Actual and expected rates and standard errors for tuberculin positive adults 

25-74 years, by sex and farm-nonfarm residence: United States, 1971-72 

Sex and residence Actual Expec:ted 

-- 

Both sexes 

Farm------------------------- 

Nonfarm---------------------- 

Men 

11.4 214.0 0.48 3.33 

22.0 21.3 1.03 1.91 

Farm------------------------- *25.2 *29.2 

Nonfarm---------------------- 24.2 24.0 

Women 

Farm------------------------- 

Nonfarm---------------------- 

*1.1 *20.3 

20.0 19.0 

1 Actual/Expected1 Standard error 

YcO.86 

1.01 

gco.05 

1.05 

*8.31 

2.45 

9~1.56 

2.15 

lActual/Expected means actual divided by expected. 

22 
.Table 7. Prevalence rates and standard errors for tuberculin positive adults 25-74 

years, by age, sex, and family income: United States, 1971-72 

Age and sex 

Both sexes 25-74 years----- 

25-34 years---------------------- 

35-44 years---------------------- 

45-54 years---------------------- 

55-64 years---------------------- 

65-74 years---------------------- 

Men 25-74 years--..---------..- 

25-34 years---------------------- 

35-44 years---------------------- 

45-54 years---------------------- 

55-64 years---------------------- 

65-74 years---------------------- 

Women 25-74 years------------ 

25-34 years---------------------- 

35-44 years---------------------- 

45-54 years---------------------- 

55-64 years---------------------- 

65-74 years---------------------- 

Annual family income 

Less than ;;,;;;- $lo,ooo ';;;i $; ,;;;- $lo,ooo 

$5,000 ' Or more $5,000 ' or more 

25.3 

Rate per 100 

‘k15.6 

*28.8 

36.2 

20.7 

26.4 

37.4 

*28.0 

*28.0 

Jr44.2 

*32.0 

46.1 

19.2 

*9.8 

*29.4 

*33.6 

16.8 

12.2 

24.5 17.4 

22.3 *3.0 

24.3 Jt10.3 

30.5 26.5 

24.5 27.9 

18.8 54.2 

27.8 18.2 

*28.0 

*24.6 

*34.6 

*26.3 

*22.3 

21.4 

*18.2 

*23.9 

*26.8 

*22.2 

*16.3 

*0.4 

*lo.8 

26.9 

24.5 

73.7 

16.7 

*5.2 

*9.8 

26.0 

Jr31.7 

*33.5 

Standard error 

4.20 

*lo.62 

*9.42 

9.12 

4.82 

3.36 

4.15 

*16.12 

*12.73 

*12.41 

*11.62 

7.65 

4.53 

*lo.42 

*11.87 

*lo.52 

5.37 

3.70 

3.57 2.11 

6.62 *1.65 

6.34 *3.31 

6.89 5.20 

5.47 5.38 

5.38 8.90 

5.01 2.44 

*11.17 

*11.24 

*lo.23 

*8.25 

*9.79 

*0.37 

*4.33 

67% 

11:15 

3.68 2.19 

*7.20 

*9.82 

*8.85 

*6.70 

*9.40 

Jr3.26 

‘k4.84 

6.90 

*9.72 

*15.45 

x 

23 
Table 8. Actual and expected rates and standard errors for tuberculin positive adults 

25-74 years, by sex and education: United States, 1971-72 

Sex and education Actual Expected Actual/Expected' Standard error 

Both sexes 

Less than 5 years------------ Jr40.8 *25.6 

5-8 years ---"-----"---"------ 30.3 2!4.7 g-12 years------------------- 20.9 2!0.9 

13 years or more------------- 14.5 1.9.8 

pgl 

Less than 5 years------------ e33.3 *33.4 

5-8 years -------------"----"- 36.3 2!8.1 g-12 years------------------- 27.4 214.1 

13 years or more------------- 13.5 2:1.4 

Women 

Less than 5 years------------ 9~46.8 *19.4 5-8 years-------------------- 23.7 20.9 9-12 years------------------- 17.3 19.1 

13 years or more------------- 16.0 17.4 

lActual/Expected means actual divided by expected. 

-- 

-- 

*1.59 Jr11.98 

1.23 4.79 

1.00 2.56 

0.73 2.71 

*1.00 *14.35 

1.29 6.87 

1.14 3.67 

0.63 2.25 

*2.41 *18.14 

1.13 4.28 

0.91 2.70 

0.92 4.37 

24 
Table 9. Prevalence rates and standard errors for tuberculin positive adults 25-74 

years, by sex and usual activity: United States, 1971-72 

Sex, rate, and standard error 

Both sexes 

Actual ---_-------------_--____________________ 

Expected ---_---------_------------------------ 

Actual/Expected'------------------------------ 

Standard error -------------------------------- 

Men 

Actual---------------------------------------- 

Expected --------------------__________________ 

Actual/Expected' ---_-------------------------- 

Standard error -------------------------------- 

Women 

Actual---------------------------------------- 

Erected-------------------------------------- 

Actual/Expectedl------------------------------ 

Standard error -------------------------------- 

Working 

20.4 

21.1 

0.97 

2.68 

21.8 

22.2 

0.98 

2.53 

18.3 

19.4 

0.94 

3.80 

Keeping house Other 

19.3 

18.7 

1.03 

1.79 

19.3 

18.7 

1.03 

1.79 

E . 

1.07 

5.53 

33.8 

32.4 

1.04 

5.55 

*27.1 

*21.3 

*1.27 

*11.63 

lActual/Expected means actual divided by expected. 

25 
Table 10. Actual and expected rates and standard errors for tuberculin positive adults 

25-74 years, by sex and industry: United States, 1971-72 

= 

1 

5 

6 

7 

8 

- 

Industry 

- 

r 

Agriculture, forestries, and 

fisheries--------------------------- 

Mining and construction-------------- 

Manufacturing------------------------ 

Transportation, communication, utilities--------------------------- 

Wholesale and retail trade----------- 

Finance, insurance,real estate------- 

Services----------------------------- 

Public administration---------------- 

Jr23.4 *25.5 *0.92 

*31.1 *24.0 *1.30 

21.2 20.8 1.01 

6117.3 

17.1 

*26.9 

19.0 

*21.9 

- 

lActual/Expected means actual divided by expected. 

- 

Actual 

- 

Both sexes 

Expected 

*19.4 *0.89 

20.5 0.83 

*23.5 *1.14 

21.4 0.89 

*21.9 *1.00 

Actual/ 

Expected1 

1 *7.15 

*10.77 II 

Standard 

error 

*7.15 

*10.77 

4.39 

*8.74 

3.48 

*10.34 

2.10 

*7.29 

26 
Table 10. Actual and expected rates and standard errors for tuberculin positive adults 

25-74 years, by sex and industry: United States, 1971-72-Con. 

Men Women 

Actual Actual/ 

Expected Expected1 'Qmdard Actual error Expected Actual/ 

Expected1 

Standard 

error 

22.2 27.3 0.81 6.88 *28.2 *18.2 Jc1.55 *30.78 

*26.8 *23.7 *1.13 Jr10.74 *68.2 *24.8 *2.75 *41.19 

22.5 21.1 1.07 4.23 *17.8 *19.9 *0.89 *9.14 

*20.2 *lg.6 *1.09 *lo.36 *8.1 *22.0 *0.37 *7.59 

*lg.8 *22.4 *0.84 *5.01 *l.5.3 *lg.6 *0.82 *6.92 

52.9 28.8 1.84 14.40 *0.6 *18.1 *0.03 *1.06 

18.2 23.7 0.77 3.70 19.5 19.6 0.99 1.90 

*27.1 Jc25.1 *1.08 *lo.25 *13.5 *16.6 *0.81 *5.93 

- 

4 

5 

6 

7 

8 

- 

27 
Table 11. Actual and expected rates and standard errors for tuberculin positive 

adults 25-74 years, by sex and occupation: United States, 1971-72 

- 

- f 

Occupation 

1 Professional and technical----------- 

2 Managers and administrators---------- 

3 Sales workers------------------------ 

4 Clerical ----------------------------- 

5 Craftsmen---------------------------- 

6 Operatives, except transport--------- 

7 Transport, equipment operatives------ 

8 Laborers, except fan---------------- 

9 Service workers---------------------- 

10 Private household workers------------ 

11 Farm---------------------------,------ 

Actual 

- 

e12.7 

20.5 

el7.2 

18.2 

21.5 

18.3 

5c31.5 

e42.7 

24.4 

9c31.4 

*32.1 

- 

Both sexes 

Expected 

*20.3 

21.5 

Jc21.7 

19.5 

22.4 

21.5 

*19.8 

a25.6 

19.7 

9t22.6 

fc23.5 

Actual/I 

Expected 

9~0.63 

0.95 

gco. 79 

0.93 

0.96 

0.85 

Jc1.59 

W.67 

1.24 

k1.39 

e1.37 

II 

1 Standard 

error 

*4.44 

5.71 

*8<,43 

2,,67 

5.,85 

4.93 

Jc15.02 

*13.20 

3.75 

Jt11.19 

Jr14.00 

1 Actual/Expected means actual divided by expected. 

26 
Table 11. Actual and expected rates and standard errors for tuberculin 

adults 25-74 years, by sex and occupation: United States, 1971-72-Con. 

positive 

I 

Actual 

*12.4 

21.8 

*24.2 

*35.3 

22.8 

*13.6 

*33.2 

*40.7 

*39.1 

*31.9 

Expected 

*21.2 

22.4 

*23.2 

*23.8 

22.6 

*22.5 

6119.3 

*26.0 

Jr22.9 

*24.7 

Men 

Actual/ 

Expected' 

*0.59 

0.97 

*1.04 

Jr1.48 

1.01 

*0.60 

*1.72 

*1.57 

*1.71 

*1.29 

Standard 

error 

*4.80 

5.75 

Jr10.68 

*lg.80 

5.50 

*5.21 

*15.08 

*13.66 

*11.46 

*20.00 

Actual 

*13.3 

*16.1 

*5.0 

14.3 

*24.5 

*17.8 

*61.4 

*17.7 

*31.4 

Jr32.5 

Women 

Expected 

*lg.6 

Jr18.5 

*19.2 

18.5 

*20.2 

*23.4 

Jc21.1 

Jrl8.2 

*22.6 

*18.4 

Actual/ 

Expected1 

*0.72 

*0.87 

*0.26 

0.77 

*1.21 

JrO.76 

*2.91 

*0.97 

*1.39 

*I..77 

Standard 

error 

Jr6.32 

*lo.65 

*7.46 

3.92 

*lo.86 

Jc30.69 

Jr47.58 

*5.57 

*11.19 

*25.00 

- 

T 

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

- 

29 
Table 12. Actual and expected rates and standard errors for tuberculin positive adults 

25-74 years, by sex and marital status: United States, 1971-72 

Sex, rate, and 

standard error 

Both sexes 

Married Widowed Never married Divorced Separated 

Actual------------------------- 21.3 17.6 

Expected----------------------- 21.6 21.9 

Actual/Expectedl--------------- 0.99 0.80 

Standard error----------------- 1.68 4.64 

Men 

Actual------------------------- 23.4 

Expected----------------------- 24.0 

Actual/Expectedl--------------- 0.98 

Standard error----------------- 2.26 

37.8 6119.8 

33.4 *22.3 

Women 

Actual -----_--------___-------- 

Expected----------------------- 

Actual/Expectedl--------------- 

Standard error----------------- 

19.0 

19.0 

1.00 

1.95 

1.13 

16.91 

j&i 

. 

0.74 

4.21 

Marital status 

*17.5 

*20.3 

-kO.86 

*6.90 

*0.89 

Jc10.36 

*16.0 *30.3 Jc20.5 

*18;8 *18.0 *18.6 

*0.85 *1.68 *1.:10 

*8.68 *8.53 *7.30 

33.4 

21.4 

1.56 

7.91 

5144.0 

*32.7 

*1.35 

*18.36 

*27.6 

*20.4 

*1.35 

Jr12.96 

Jr44.6 

*24.4 

*1.83 

*18.13 

lActual/Expected means actual divided by expected. 

30 
Table 13. Actual and expected rates and standard errors for tuberculin positive adults 

25-74 years, by number of rooms in place of residence: United States, 1971-72 

Number of rooms 

Rate and 

standard error 

Actual-------------- *53.3 

Expected------------ *30.2 

Actual/Expected'---- Jc1.76 

Standard error------ *20.84 

2 

*37.9 30.8 

*24.3 21.8 

el.56 1.41 

*13.55 4.65 

3 4 5 6 

-t-t 

21.9 18.6 25.5 

21.1 21.5 21.2 

lActual/Expected means actual divided by expected. 

7 8 

17.4 

22.8 

0.76 

2.48 

19.3 

19.9 

0.97 

5.31 

9 or 

more 

*9,1 

*22.5 

*0.40 

*4.43 

31 
APPENDIXES 

CONTENTS 

I. Statistical Notes.. ........................................................ ............................................................................. 33 

The Survey Design.. ............................................................................................................................. 33 

Nonresponse ....................................................................................................................................... 34 

Missing Data ........................................................................................................................................ 35 

Expected Values ................................................................................................................................. 36 

Small Numbers ...................................................... . ............................................................................. 36 

Sampling and Measurement Error .......................... ............................................................................. 36 

II. Demographic and Socioeconomic Terms.. .................. I,........................................................................... 37 

LIST OF APPENDIX TABLES 

I. Percent distribution of nonresponse adjustment factors, HANES, Stands 01-35, 1971-1972 . . . . . . . . . . . . . . . . . . 35 

32 
APPENDIX I 

STATISTICAL NOTES 

The Survey Design 

The sampling plan for the first 65 stands of the 

Health and Nutrition Examination Survey (HANES) 

followed a stratified multistage probability design in 

which a sample of the civilian noninstitutionalized 

population of the coterminous United States, l-74 

years of age, was selected. Excluded from the selection were persons residing in Alaska and Hawaii 

and those within the coterminous United States confined to institutions or residing on reservation lands 

of American Indians. Successive elements dealt with 

in the process of sampling were the primary sampling 

unit (PSU), census enumeration district (ED), segment 

(a cluster of households), household, eligible persons, 

and finally sample persons. 

The starting points in the first stage of this design 

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 either a standard metropolitan statistical area 

(SMSA), a single county or two or three contiguous 

counties. The PSU’s were grouped into 357 strata 

for use in the Health Interview Survey and subsequently collasped into 40 super strata for use in 

Cycle II and III of the Health Examination Survey 

and HANES. 

Fifteen of the 40 super strata contained a single 

large metropolitan area of more than 2,000,OOO population. These 15 large metropolitan areas were chosen 

into the sample with certainty. The 25 noncertainty 

strata were classified into four broad geographic 

regions of approximately equal population and crossclassified into four broad population density groups 

in each region. Then a modified Goodman-Kish controlled selection technique was used to select two 

PSU’s from each of the 25 noncertainty super strata 

with the probability of selection of a PSU proportionate 

to its 1960 population so that proportionaterepresentadon of specified State groups and rate of population 

change classes was maintained in the sample>In this 

manner a total first stage sample of 65 PSU’s was 

selected. These 65 sample PSU’s or stands are the 

areas within which a sample of persons would be 

selected for examination over a J-year survey period. 

In order to produce national estimates of the nutritional status of the U.S. population at an earlier date, 

a probability subsample of 35 stands of the 65 stands 

was selected. This 35 stand subsample also made it 

possible to produce national estimates of certain other 

aspects of health status in the population that were 

critically needed at an earlier date and examination 

components that for logistic reasons could not be 

continued for the remainder of the 65 stands. Included 

among the 35 stands are 10 of the 15 large certainty 

metropolitan areas and one stand from each of the 25 

noncertainty super strata. The reduction from 15 to 

10 large metropolitan areas was accomplished by 

randomly selecting one stand from multiple-stand 

standard metropolitan statistical areas, e.g., selecting 

the southern half of the Chicago SMSA to represent 

the entire SM3A. (This selection procedure was based 

on operational considerations and, although unbiased 

is recognized as not being statistically optimal.) 

It is this subsample of 35 stands upon which the findings 

contained in this report are based. 

Although the 1970 Census data were used as the 

frame for selecting the sample within PSU’s when they 

became available, the calendar of operations required 

that 1960 Census data be used for the 3%stand sample 

of HANES. Census enumeration districts (ED’s) in 

each PSU were divided into segments of an expected 

six housing units each. In urban ED’s the segments 

were clusters of six addresses from the 1960 Census 

listing books. For ED’s not having usable addresses, 

area sampling was employed and consequently some 

variation in the segment size occurred. To make the 

sample representative of the current population of the 

United States, the address or list segments were supplemented by a sample of housing units that had been 

constructed since 1960. 

Within each PSU a systematic sample of segments 

was selected. The enumeration districts which fell 

into the sample were coded into one of two economic 

classes. The first class. identified as the “poverty 

stratum,” was composed of “Current Poverty Areas” 

33 
that had been identified by the U.S. Bureau of the 

Census in 1970 (pre 1970 Census), plus other ED’s 

in the PSU with a mean income of less than $3,000 

in 1959 (based on 1960 Census). The second economic 

class, the “nonpoverty stratum,” includes all ED’s 

not designated as belonging to the “poverty stratum.” 

All sample segments classified as being in the 

“poverty Stratum” were retained in the sample. For 

those sample segments in “nonpoverty stratum” ED’s, 

the selected segments were divided into eight random 

subgroups and one of the subgroups was chosen to 

remain in the HANES sample. This procedure permits a separate analysis with adequate reliability 

of those classified as being below the poverty level 

and those classified as being above the poverty level. 

After identification of the sample segments, a 

list of all current addresses within the segment 

boundaries was made, and the households were interviewed to determine the age and sex of each 

household member as well as other demographic 

and socioeconomic information required for the survey. 

To select the persons in sample segments to be 

examined in HANES, all household members aged l-74 

in each segment were listed on a sample selection 

worksheet with each household in the segment listed 

serially. The number of household members in each 

of the six age-sex groups shown below were listed 

on the worksheet under the appropriate age-sex group 

column. The sample selection worksheets were then 

put in segment number order and a systematic random 

sample of persons in each age-sex group was selected 

to be examined using the following sampling rates. 

Ages Rate 

1-5 years ............................................................ 

6-19 years .......................................................... 

20-44 years, men ................................................ 

20-44 years, women ........................................... 

45-64 years ....................................................... 

65-74 years ........................................................ 

The persons selected in the 35 stand sample of 

HANES comprise a representative sample of the target 

population and included 14,147 sample persons l-74 

years of age of whom IO.126 or 71.6 percent were 

examined. When adjustments are made for differential sampling for high risk groups, the response 

rate becomes 72.8 percent. 

The one-fifth subsample of those in the total 

sample aged 25-71 years was designated to receive 

a more detailed examination and to obtain further 

data on health status and unmet health care needs. 

It was chosen systematically after a random start 

using the following sampling rates: 

Age 

Rate applied to Resultant effective 

nutrition sample 

for detailed 

sampling rate 

subsample 

for detailed 

subsample 

25-44 years, men . . . . . . 215 l/IO 

25-44 years, women . . If5 II10 

45-64 years . . . . . ..__..... 315 3120 

65-74 years . . . . . . . . . . . . . . l/4 I/4 

The adults 25-74 years of age in this 35-stand 

detailed sample of HANES are also a representative 

sample of that target population and included 2,798 

sample adults 25-74 years of age of whom 1,892 or 

67.6 percent were examined. When adjustments are 

made for differential sampling in the older groups, 

the effective response rate is 68.7 percent. 

All data presented in this report are based on 

“weighted” observations. That is, data recorded for 

leach sample person are inflated to characterize the 

subuniverse from which that sample person was drawn. 

The weight for each examined person is a product of 

the reciprocal of the probability of selecting the person, 

an adjustment for nonresponse cases (i.e., persons 

not examined), and a poststratified ratio adjustment 

which increases precision by bringing survey results 

into closer alignment with known U.S. population 

figures. 

A more detailed description of the survey design 

and selection technique can be found in the Plan and 

Operation of a Health and Nutrition Examination Survey, U.S. 1971-1973,Vital and Health Statistics, Series 

I.. No. 10a. 

Nonresponse 

In any health examination survey, after the sample 

is identified and the sample persons are requested to 

participate in the examination, the survey meets one 

of its more severe problems. Usually a sizablenumber 

Iof sample persons will not participate in the examina- 

,tion. Whether or not an individual participates is 

determined by many factors, some of them uncon- 

!trollable, and therefore, may be reasonably treated 

as an outcome of a random event with a particular 

probability of occurrence. If these probabilities of 

participation were known and greater than zero for 

all persons, then the examined persons would constitute a probability sample from which unbiased estimates of the target population could be derivsed. 

In this situation, the effect of nonparticipation would 

only be to reduce the sample size, thereby increasing 

the sampling errors of examination findings. However, 

in practice a potential for bias due to nonresponse 

exists since the exact probabilities are never known. 

A further potential for bias exists if: (1) a sizable 

proportion of sample persons have a zero probability of participation, that is, they would never agree 

34 
to participate in an examination survey of the same 

procedures and inducements, and also (2) these persons differ from other sample persons with respect 

to characteristics under examination. It is for these 

reasons that intensive efforts are made in HANES 

to develop and implement procedures and inducements 

that would reduce the number of nonrespondents and 

thereby reduce the potential of bias due tononresponse. 

These procedures and inducements are discussed in 

the Plan and Operation of the Health and Nutrition 

Examination Survey, U.S. 1971-1973, Vital and Health 

Statistics, Series 1, No. 10a. 

Despite these intensive efforts 27.2 percent of 

the sample persons l-74 years and 31.3 percent of 

those 25-74 years from the first 35 stands were not 

examined. Consequently, the potential for a sizable 

bias does exist in the estimates in this publication. 

From what we know about the nonrespondents and 

the nature of nonresponse we believe that thelikelihood 

of sizable bias is small. For instance, only a small 

proportion of persons gave reasons for nonparticipation 

which would lead to the belief that they would never 

agree to participate in examination surveys and that 

they may differ from examined persons with respect 

to the characteristic under examination. Only 15 

percent of the nonrespondents gave as their’ reasons 

for nonparticipation personal illness, physically unable, 

pregnant, anti-doctor, or fear of finding something 

wrong. Typical among the reasons given by the other 

nonrespondents were: unable because of work, school, 

or household duties; suspicious or skeptical of the 

program; just not interested in participating; and private medical care sufficient or just visited doctor. 

An analysis of medical history data obtained 

for most nonexaminees as well as examinees also 

supports the belief that the likelihood of sizable bias 

due to nonresponse is small. No largedifferences 

were found between the examined group and nonexamined group for the statistics compared. For example, 

11 percent of persons examined reported having an 

illness or condition which interferes with their eating 

as compared to 9 percent of persons not examined 

but who had completed a medical history. The percent 

of persons examined reporting ever being told by a 

doctor that they had arthritis was 20 percent; the 

percent for high blood pressure was 18 percent and 

for diabetes was 4 percent. The corresponding percents for nonexamined persons were: arthritis, 17 

percent; high blood pressure, 21 percent; and diabetes 4 percent. 

As was mentioned earlier, the data in this report 

are based on weighted observations, and one of the 

components of the weight assigned to an examined 

person was an adjustment for nonresponse. Since 

the probabilities of participation are not known for 

sample persons in HANES, a procedure was adopted 

which multiplies the reciprocal of the probability of 

selection of sample persons by a factor which brings 

estimates based on examined persons only up to a 

level which would have been achieved if all sample 

persons had been examined. This nonresponse adjustment factor is the ratio of the sum of sampling 

weights for all sample persons within a relatively 

homogeneous class defined by age, sex, and poverty 

status to the sum of sampling weights for all responding 

sample persons within the same homogeneous class. 

To the degree that homogeneous groups can be defined which are also homogeneous with respect to the 

characteristics under study, the procedure can be 

effective in reducing the potential bias from JlOnresponse. 

For the 35 stand sample of HANES, persons were 

grouped into 20 age-sex-poverty status groups within 

each stand, yielding seven hundred separate cells with 

an average membership of about 20 sample persons 

each. These adjustment factors are distributed among 

examined persons as shown in table I. 

Table I. Percent distribution of nonresponse adjustment factors, HANES, Stands 

01-35, 1971-1972 

I 

Size of factor Percent 

distribution 

Tot-l------------- 100.0 

1.00-1.24--------------- 38.4 1.25-1.49--------------- 31.6 1.50-1.74--------------- 12.9 1.75-1.99--------------- 

2*@-&2.4g --------------- 24 2.50-2.99--------------- 

3.00-3.03--------------- ::2 

Missing Data 

Examination surveys are subject to the loss of information not only through the failure to examine all 

sample persons but also from the failure to obtain and 

record all items of information for examined persons. 

The tuberculin test was administered to 1,580 or 83.5 

percent of those adults examined and readings on the 

degree of reaction were obtained for 1,494 or 79.0 

percent of the examinees. An additional 2.4 percent were 

not tested but gave as a reason for refusal a history 

of tuberculosis, receiving INH prophylaxis, or recent 

tuberculin tests with known reactions. No estimates 

were imputed for the 18.6 percent without useable 

tuberculin skin test results or histories. The 6.6 percent not tested because they were examined in the last 

day or two at a location are unlikely to have biased the 

findings. Among the remaining 12.0 percent some 

potential biasing effects may exist but in either di35 
rection. The proportion returning for reading was 

slightly greater among those living in large urban 

areas where the prevalence of ruberculosis and hence 

chance of exposure is greater than elsewhere. 

Possibly also contributing to a positive bias is the 

greater likelihood of positive than negative reactors 

to return for a reading. However, it is likely that the 

prevalence and characteristics of positive tuberculin 

reaction among those 18.6 percent whose test results 

were not available would not be markedly different 

than those with known reactions. 

Expected Values 

In the detailed tables both the actual and expected 

prevalence rates are shown for adults in the various 

demographic groups. The expected values are obtained 

by assuming that the national age-specific rates apply 

within the appropriate age-sex subgroups for which 

the value is to be derived. 

For example, if in an area (e.g., the Northeast) 

estimates from the Health Examination Survey show 

n, men in the ith age group (j = 25 - 34, 35 - 44 - 65 - 

74; CR,=~) and the estimates of prevalence rates for 

all U.S. men in the jth age group to be Xi> then the 

expected prevalence rate for men in that area is: 

1 

n c n,x, 

The specific area may have higher values for 

younger men and lower values for older men than in the 

other areas. In that case the expected rates may obliterate one or both of these differentials. These types 

of limitations need to be kept in mind in interpreting 

these data. The standard error of the difference between 

an actual and an expected rate may be approximated 

by the standard error of the actual value. 

Small Numbers 

In some tables magnitudes are shown for cells for 

which the sample size is so small that the sampling 

error may be several times as great as the statistic 

itself. Obviously in such instances the numbers, if 

shown, have been included to convey an impression 

of the overall story of the table. 

Sampling and Measurement Error 

In the present report, reference has been made 

to efforts to minimize bias and variability of measurement techniques. The potential of residual bias 

due to the high nonresponse rate has also been discussed. 

The probability design of the survey makes possible the calculation of sampling errors. Traditionally 

the role of the sampling error has been the determination of how imprecise the survey results may 

be because they come from a sample rather than 

from the measurement of all elements in the universe. 

The estimation of sampling errors for a study 

of the type of the Health and Nutrition Examination 

Survey is difficult for at least three reasons: (1) 

measurement error and “pure” sampling error are 

confounded in the data-it is not easy to find a procedure which will either completely include both 

or treat one or the other separately; (2) the survey 

design and estimation procedure are complex, and, 

accordingly, require computationally involved techniques for the calculation of variances; and (3) hundreds of statistics are presented in the tables in this 

report, many for subclasses of the population for 

which there are a small number of sample cases. 

Estimates of sampling error are obtained from the 

sample data and are themselves subject to sampling 

error when the number of cases in a cell is small or, 

even occassionally, when the number of cases is substantial. 

Estimates of the standard errors for selected 

statistics used in this report are presented in the 

detailed tables. These estimates have been prepared 

by a replication technique which yields overall variability through observation of variability among random subsamples of the total sample. Again, readers 

are reminded that these estimated sampling errors 

do not reflect any residual bias which might still be 

present after the attempted correction for nonrei 

sponse. The standard error is primarily a measure 

of sampling variability, that is, the variations that 

might occur by chance because only a sample of the 

population is surveyed. As calculated for this report, 

the standard error also reflects part of the variation 

which arises in the measurement process. It does not 

include estimates of any biases which might lie in the 

data. The chances are about 68 out of 100 that an estimate from the sample would differ from a complete 

census by less than the standard error. The chances 

are about 95 out of 100 that the difference would be 

less than twice the standard error and about 99 out 

of 100 that it would be less than 2% times ss large. 

--000 

36 
APPENDIX II 

DEMOGRAPHIC AND SOCIOECONOMIC TERMS 

Age.-The age recorded for each examinee was 

the age at last birthday at the time of examination. The 

age criterion for inclusion in the sample used in this 

survey were defined as age at time of Census interview. In this sample there were 8 examinees who were 

74 years of age at the time of interview but 75 years 

of age at examination. In the adjustment and weighting 

procedures used to produce national estimates, these 

persons were included in the 74 year old group. 

Race.-Race was recorded as “white,” “Negro,” 

or “other . ” “Other” includes Japanese,‘Chinese, American Indian, Korean, Eskimo and all races other than 

white and Negro. Mexicans were included with “white” 

unless definitely known to be American Indian or of 

other nonwhite race. Negroes and persons of mixed 

Negro and other parentage were recorded as “Negro.” 

When a person of mixed racial background is uncertain about his race, the race of his father was recorded. 

Geographic region. -The forty-eight continguous 

States and the District of Columbia (not Alaska and 

Hawaii) were stratified into four broad geographic 

regions of about the same population size. With a 

few exceptions the compositions of the regions are 

as follows: 

Region States Included 

Northeast -------Maine, New Hampshire, Vermont, 

Massachusetts, Connecticut. Rhode 

Island, New York. New Jersey, 

Pennsylvania 

Midwest- -------Ohio, Michigan, Indiana. Illinois, 

Wisconsin, Minnesota, Iowa, Missouri 

South -----------Delaware, Maryland, Virginia. West 

Virginia, Kentucky, Arkansas, 

Tennessee, North Carolina, South 

Carolina, Georgia, Florida, Alabama, 

Mississippi, Louisiana, District of 

Columbia 

West -----------Washington, Oregon, Idaho, Montana, 

Wyoming, Colorado, Utah, Nevada, 

California, Arizona, New Mexico, 

Texas, Oklahoma, Kansas, Nebraska, 

South Dakota, North Dakota 

In a few instances the actual boundaries of the 

regions do not follow State lines. Some strata in the 

Midwest and South Regions include PSU’s actually 

located in the West Region. Similarly, some strata 

in the West Region contain PSU’s located in the 

Midwest and South Regions. 

PopuZQtion density. -The United States population 

was divided into five population groups of approximately 

the same size. These groups were defined differently 

for the four geographic regions as is shown below. 

For the very large SMSA’s, except those in the South 

Region, the criterion for inclusion was population size; 

these SiMSA’s were chosen for the sample with certainty. In the South Region, the “largest SMSA’s” were 

defined in the same way as “other large SMSA’s,” but 

were put in a different stratum for sampling purposes. 

Region 

Northeast 

Largest SMSA’s 

Other large SMSA’s 

Other SMSA’s 

Not in SMSA, urban 

Not in SMSA, rural 

Midwest 

Largest SMSA’s 

Other large SMSA’s 

Other SMSA’s 

Class Composition 

The SM.SA’s population 

was greater than 2.4 million. 

Seventy percent or more of 

the SMSA’s population was 

urban. 

Less than 70 percent of 

the SAilSA’s population 

was urban. 

Forty percent or more of 

the population was urban. 

Less than 40 percent of 

the population was urban. 

The SMSA’s population was 

greater than 3 million. 

Ninety percent or more of 

the Sh4SA’s population was 

urban. 

Less than 90 percent of 

the S&ISA’s population was 

urban. 

37 
Not in SMSA, urban 

Not in SMSA, rural 

South 

Largest SMSA’s 

Other large SMSA’s 

Other SMSA’s 

Not in SMSA, urban 

Not in SMSA, rural 

West 

Largest SMSA’s 

Other large SMSA’s 

Other SMSA’s 

Not in SMSA, urban 

Not in SMSA, rural 

Thirty-four percent or 

more of the population 

was urban. 

Less than 34 percent of the 

population was urban. 

Ninety percent or more of 

the SMSA’s population was 

urban. 

Ninety percent or moreof 

the SMSA’s population was 

urban. 

Less than 90 percent of 

the SMSA’s population was 

urban. 

Thirty percent or moreof 

the population was urban. 

Less than 30 percent of 

the population was urban. 

The SMSA’s population was 

greater than 2.5 million. 

Seventy-two percent or 

more of the SMSA’s population was urban. 

Less than 72 percent of 

the SMSA’s population was 

urban. 

Thirty-six percent or more 

more of the population 

was urban. 

Less than 36 percent of 

the population was urban. 

Urban-ruval.-The classification of urban-rural 

areas is that used in the 1960 Census. According to 

the 1960 definition, those areas considered urban are: 

(a) places of 2,500 inhabitants or more incorporated 

as cities, boroughs, villages, and towns (except towns 

in New England, New York, and Wisconsin); (b) the 

densely settled urban fringe, whether incorporated or 

unincorporated, of urbanized areas; (c) towns in New 

England and townships in New Jersey and Pennsylvania 

which contain no incorporated municipalities as subdivisions and have either 2,500 inhabitants or more, 

or a population of 2.500 to 25,000 and a density of 

1,500 persons per square mile; (d) counties in States 

other than the New England States, New Jersey, and 

Pennsylvania that have no incorporated municipalities within their boundaries and have a density of 

1,500 persons or more per square mile; and (e) 

unincorporated places of 2,500 inhabitants or more 

which are not included in any urban fringe. The remaining population is classified as rural. 

By means of the first digit of the identification 

code on the household questionnaire, the urban and 

38 

rural population is divided into the following categories according to population: (1) urban, 3,000,OOO or 

more; (2) urban, l,OOO,OOO-2,999,999; (3) urban, 

250,000-999,999; (4) urban, under 250,000; (5) urban 

not in urbanized area, 25,000 or more; (6) urban 

not in urbanized areas, lO,OOO-24,999; (7) urban not 

in urbanized area, 2,500-9,999; and (8) rural. 

SMSA-Not in SMS4.--By means of the second digit of 

the identification code on the household questionna.ire, 

the population is classified as living “in central city” 

of a standard metropolitan statistical area (SMSA), 

“not in central city” of an SMSA, or “not in SMSA.” 

The definitions and titles of SMSA’s are established 

by the U.S. Office of Management and Budget with the 

advice of the Federal Committee on Standard Metropolitan Statistical Areas. An SMSA consists of a 

county or group of contiguous counties (except in 

New England) which contains at least one central 

city of 50,000 people or more, or “twin cities” with 

a combined population of at least 50,000 people. In 

addition, other contiguous counties are included in 

an SMSA if, according to certain criteria, they are 

socially and economically integrated with the central 

city. Definitions of SMSA’s which identify the composition and structure of each are given in U.S. Office 

of Management and Budget, Standard Metropolitan 

Statistical Areas, 1967 Edition. Persons “in central 

city” of an SMSA are therefore defined as those w’hose 

residency is in the city or cities of the standard metropolitan statistical area title. Persons who reside 

in an SMSA but not in the city given in the SMSA title 

are considered “not in central city.” Note: It is possible for rural-farm and rural-nonfarm residents 

(as defined above) to be coded as “in SMSA.” 

Family income. -The income recorded is the 

total income received during the 12 months prior to 

the interview by the head of the household and all 

other household members related to the head. This 

income is the gross cash income (excluding pay 

in kind) except in the case of a family with its own 

farm or business. In that instance net income is recorded. Also included is the income of a member of 

the Armed Forces who is living at home with his 

family (even though he is not considered a household 

member). If he is not living at home, allotments and 

other money received by the family from him are 

included in the family income figure. 

Education .-The only grades counted are those 

that have been attended in a regular school where 

persons are given formal education-either graded 

public or private schools, day or night, full-time 

or part-time attendance. A “regular” school is one 

which advances a person toward an elementary or 

high school diploma, or a college, university, or 

professional school degree. Education received in 

vocational, trade, or business schools outside, the 

regular school system are not counted in determining 
the highest grade of school completed. If a person ders the most important or the one which he has had 

attended school in a foreign country, an ungraded longer. A person who has not begun work at a new 

school, under a tutor, or under other special cir- job, is looking for work, or is on layoff from a job 

cumstances, the nearest equivalent of his highest is questioned about his last full-time civilian job 

grade attended. or business. 

IndUStYY .-The industry in which a person reports 

he is working is classified by the major activity of 

the establishment in which he works. The only exceptions to this are those few establishments classified according to the major activity of the parent 

organization such as research laboratories, warehouses, repair shops, and storage garages when these 

kinds of establishments exist primarily to serve their 

own parent organizations rather than the public or 

other organizations. The industry groupings shown 

below are the same as those used by the U.S. Bureau 

of the Census for the 1970 Census. Codes for these 

industries are listed in the U.S. Bureau of the Census 

publication, 1970 Census of Population Alphabetical 

Index of Industries and 0ccupatio:a.s. U.S. Government 

Printing Office, Washington, D.C., 1971. 

The occupation groupings shown below are the 

same as those used by the U.S. Bureau of the Census 

for the 1970 Census. Codes for these occupations 

are listed in the U.S. Bureau of the Census publication, 

1970 Census of Pop’zlation Alphhetical Index of Industries and Occupa Cons, U.S. Government Printing 

Office, Washington, DC., 1971. 

OGGU$CLtiOTZ Groups 

Professional, technical, and kindred workers 

Managers and administrators, except farm 

Sales workers 

Clerical and kindred workers 

Craftsmen and kindred workers 

Operatives, except transport 

Transport equipment operatives 

Laborers, except farm 

Farmers and farm managers 

Farm laborers and farm foremen 

Service workers, except private household 

Private household workers 

Occupation not reported 

Industry Groups 

Agriculture, forestry, and fisheries 

Mining 

Construction 

Manufacturing 

Transportation, communication, and other public 

utilities 

Wholesale and retail trade 

Finance, insurance, and real estate 

Business and repair services 

Personal services 

Entertainment and recreation services 

Professional and related services 

Public administration 

Industry not reported 

The industry “public administration” is limited 

to the postal service, and Federal, State, and local 

public administrations. This category includes only 

uniquely governmental functions and excludes those 

activities which may also be carried out by private 

enterprise. For example, teachers in public educational facilities and nurses engaged in medical services of governmental agencies are included in the 

“professional and related services” group. 

occupation .-A person’s principal job or business 

as reported during the household interview is considered to be his occupation. If the person worked at 

a job or business during the 2 weeks preceding the 

interview, the question about his occupation (or what 

kind of work he was doing) applies to his job during 

that period. If the person works at or has more than 

one job, the questions refer to the job at which he 

spends the most time. If equal time is spent at each 

job, the questions refer to the one the person consiUswzl activity. -This item on the household questionnaire is defined as that activity (“working,” “keeping 

house,” or “something else”) in which the person has 

been engaged for most of the time between the date of 

interview and the same date 3 months earlier. “Working” 

includes paid work as an employee for someone else 

for wages, salary, commission, or “pay in kind” 

(meais, living quarters, or supplies provided in the 

place of cash wages). Also included is work in the person’s own business, professional practice, or farm. 

and work without pay in a business or farm run by 

a relative. Work done around a person’s own house 

or volunteer, unpaid work for a church or charity 

is not included in the “working” category. “Something 

else” included people in all activities besides “working” 

and “keeping house.” 

Marital status .-The five categories of marital 

status on the household questionnaire are “married,” 

“widowed,” “never married,” “divorced,” and “separated.” A respondent is not asked about the marital 

status of a person under 17 years old unless there is 

reason to believe the person is not single. A person 

whose mnrriage has been annulled is considered 

“never married.” Persons having common law marriages are considered “married.” “Separated” refers 

only to married persons who have a legal separation 

or who have parted because of marital discord. Thus 

persons separated because of the circumstances) of 

their employment, service in the Armed Forces, or 

39 
similar reasons are classified as “married,” not 

“separated.” 

Number of ?-ooms in liviw quarters. --Iincluded 

in the count are whole rooms used for living purposes 

such as living rooms, dining rooms, bedrooms, kitchens, 

finished attic or basement rooms, recreation rooms, 

permanently closed porches suitable for year-round 

use, lodgers’ rooms, and rooms used for offices by 

--000 

persons living in the housing units. Not considered 

as rooms are bathrooms, halls, foyers or vestibules, 

balconies, closets, alcoves, strip or pullman kitchens, 

laundry or furnace rooms, unfinished attics or basements, other unfinished space used for storage, open 

porches, trailers used only for bedrooms, and offices 

used only by persons not living in the housing units. 

QU.S.GOVERNMENTPRlNTlNGOFFICE: 1977--241.180:21 
VITAL AND HEALTH STATISTICS PUBLICATIONS SERIES 

Formerly Public Health Service Publication No. 1000 

Series 1. Programs and Collection Procedures.-Reports which describe the general programs of the National 

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

other material necessary for understanding the data. 

Series 2. Data Evaluation and Methods Research.-Studies of new statistical methodology including experimental 

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. 

Series 3. 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. 

Series 4. Documents and Committee Reports.-Final reports of major committees concerned with vital and 

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

and death certificates. 

Series IO. Data from 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 kiterview survey. 

Series 11. Data from the Health Examination Survey.-Data from direct examination, testing, and measurement 

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

reports: (1) estimates of the medically defined prevalence of specific 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 finite universe of persons. 

Series 12. Data from the Institutionalized Population Surveys.-Discontinued effective 1975. Future reports from 

these surveys will be in Series 13. 

Series 13. Data on Health Resources Utilization.-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 as included in regular annual or monthly 

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

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

sample surveys of those records. 

Series 21. Data on Natal&y, Marrikge, 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. Data from the National Mortality 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. 

Series 23. Data from the National Survey of Family Growth.-Statistics on fertility, family formation and dissolution, family planning, and related maternal and infant health topics derived from a biennial survey of 

a nationwide probability sample of ever-married women 1544 years 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 

Hyattsville, Md. 20782