Ilatafromthe

NATIONAL HEALTH SURVEY

Periodontal Disease

AmongYouths12-17Years

United States

Estimates of the Periodontal Index (Pi) for noninstitutionalized youths

aged 12-17 years inthe United States, byage, sex, race, family income,

education of head of household, and geographic region, and a

correlation analysis of the interrelation of the PI and selected

demographic characteristics.

DHEW Publication No. (HRA) 74-1623

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

Public Health Service

HEALTH RESOURCES ADMINISTRATION

National Center for Health Statistics

Series 11

Number141

Rockville, Md. June 1974
Series 11 reports present findings from the National Health Examination Survey, which

obtains data through direct examination, tests, and measurements of samples of _the U.S.

population. Reports 1 through 38 reIatc to the adult program, Cycle I of the Health

Examination Survey. The present report is one of a number of reports of findings from the

children and youth programs, Cycles II and III of the Health Examination Survey. These

latter reports from Cycles II and III are being published in Series 11 but are numbered

consecutively beginning with 101. it is hoped this will guide users to the data in which they

are interested.

Library of Congress Cataloging in Publication Data

Periodontal disease among youths 12-17 years, United States.

(Data from the National Health Survey, series 11, no. 141) (DHEW publicaticm no.

(HRA) 74-1623)

Supt. of Dots. no.: HE 20.2210: 11/141.

1. Periodontal disease–United States–Statistics. 2. Children–Dental Care–United

States–Statistics. I. United States. National Center for Health Statistics. II, Title.

III. Series: United States. National Center for Health Statistics. Vital and health stat ist its.

Series 11: Data from the National Health Survey. Data from the health examination survey,

no. 141. IV. Series: United States. Dept. of Health, Education, and Welfare. Publication no.

(HRA) 74-1623). [DNLM: 1. Periodontal diseases–In adolescence. 2. Periodontal

diseases–Occurrence–U.S. W2A N148vk no. 141 1974]

RA407.3.A347 no. 141 [RK361] 312’.0973s 74-4037

ISBN 0-8406 -0007-0 [312’.304’7630973]

For MO IW the Suprriutcndcut of Documcuts, U.S. Govcmmcnt Printinz olficc

—_____ WA1iugtOn, 1).C. Nt02 - Price 65 ccuts
NATIONAL CENTER FOR HEALTH STATISTICS

EDWARD B. PERRIN, Ph. D., Director

PHILIP S. LAWRENCE, SC.D., Deputy Director

DEAN E. KRUEGER, Acting Associate Director for Awdy.sis

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

ELIJAH L, WHITE, Associate Director for Data Systems

IWAO M. MORIYAMA, Ph. D., Associate Director for Znternationa~ Statistical Programs

EDWARD E. MINTY, Associate Director for Management

ROBERT A. ISRAEL, Associate Director for Operations

QUENTIN R. REMEIN, Associate Director for Program Development

PHILIP S. LAWRENCE, SC.D., Acting Associate Director for Research

ALICE HAYWOOD, Information Officer

DIVISION OF HEALTH EXAMINATION STATISTICS

ARTHUR J. McDOWELL, Director

GARRIE J. LOSEE, Deputy Director

HENRY W. MILLER, Chief Operations and Qua~ity Control Branch

JEAN ROBERTS, Chief Medical Statistics Branch

JAMES E. KELLY, D. D. S., Chief NCHS Dental Adviser

LAWRENCE E. VAN KIRK, D. D. S., Dental Adviser

Vital and Health Statistics-Series1l-No. 141

DHEW Publication No. (HRA) 74-1623

Library of Congress Catalog Card Number 74-4037
CONTENTS

Inttmcluction . . . . . .

Contents . . . . . . .

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Background and Source of Data . . . . . . . . .

I;xalninatiun . , . . . .

Nonrcxpunsc . , . . . .

i.imitutiom of Data . .

l’~’riud{mtal Index (PI) . ,

I’~riod{lntal Index Findings

.!gc . . . . . . . . . .

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lix~wctcd (Age-Control) Value

Inc[mc . . . . . . . . . . .

Iidumtion . . . . . . . . . .

Region . . . . . . . . . . . .

l)iscussi~ln . . . . . . . . . . .

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lntcv-rclatit~n uf PI and Selected Demographic Variables .

1)1I:indings lrf)m Previous HES Reports . . . . . . . . .

Sllmmar y . . . . . . . . . . . . . . . . . . . . . . . .

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

List(Jf Detailed TaMes . . . . . . . . . . . . . . . . . . .

Appcnclix I. The Dental Examination . . . . . . . . . . .

The Periodontal Index (PI) . . . . . . . . . . . . . . .

Training of Examiners . . . . . . . . . . . . . . . .. . .

Appendix 11. Demographic and Socioeconomic Terms . .

Appendix 111. Statistical Notes . . , . . . . . . . . . . .

Survey Design . . . . . . . . . . . . . . . . . . . . . .

Reliability . . . . . . . . . . . . . . .. . . . . . . . . .

SLinlpIing and Lleasurement Error . . . . . . . . . . . .

Tests of Significance . . . . . . . . . . . . . . . . . . .

SnmllNumbers . . . . . . . . . . . . . . . . . . . . .

Expected Values . . . . . . . . . . . . . . . . . . . . .

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

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

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

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

Figure does not meet standards of

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

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0.0

*
PERIODONTAL DISEASE

AMONG YOUTHS 12-17 YEARS

hh-cus J. Sanchez, Diuision of Health Examination Statistics

INTRODUCTION

Contents

This I-cpurt presents na, ional estimates of the

prLAJLdcncc and severity cf periodontal disease

,lnl(m~ youths W@ 12-1 ~ years in the United

St.[t~*s :wcurc[ing to race, sex, age, and other selc’~teci ci~moRr:lphic characteristics. The severity

,tnd prcv,llcmrc t)f periodontal disease were meast[ucd by the Periodontal Indesl (PI). A correlatil in an:dysis of the interrelation of the PI and

scl~’L.tcd dcmogr:iphic variables is also included.

Background and

Source of Data

ih~in~ 1966-70 the Division of Health Examin:it iun Stutist!cs conducted a survey of the

hc;llth uf the Nution’s you:h. The target popukLti(~n ~vas the 22.7 million noninstitutionalized

~~.S. y,.)uths aged 12-17 iiving in the United

St~ltcs (including .41MiicI and Hawaii) except

th( )SC residing on lands reserved for American

tncii:ms. A probability sample of 7,514 youths

w.ts sclerted to be rqn-esentative of the populati{~n of U.S. youths.z The sample design and the

pn~ccdurc by which the sample was selected are

cicscribcd in appendix III.

The 1966-70 survey was the third in the series

uf sanlplc surveys conducted by the Division of

Hculth Examination Statistics on specified segments of the U.S. population in which health

st;ttus was determined by direct examination.

The first survey collected information about the

health of the Nation’s adu1ts3 aged 18-79 years

and focused primarily on determining the prevalence of seIected chronic health conditions. The

second survey was desi~ed to assess health factors related to the growth and development of

the Nation’s children aged 6-12 years.4 The survey of youths was conducted in essentially the

same way as that of children. Examinations were

conducted in mobile centers that visited 40 randomly selected locations in 25 States.

Examination

A standardized examination as administered

to each consenting sample youth whose parents

or guardians also consented to his or her participation in the survey. Physicians, psychologists,

nurses, technicians, and dentists performed tests

which focused on factors related to biologic.d

and psychological aspects of growth and development. A pediatrician examined the nose,

throat, ears, heart, and neuromuscular joint

system of each youth. The teeth and their sLlpporting structure were examined by a dentist.

Intellectual development, school achievement,

and personality development were measured by

a psychologist. Other procedures included tests

of vision, hearing, exercise tolerance, grip

strength, and breathing capacity. Blood pressure

Ievek and electrocardiograms were recorded, as

were height, weight, and other body measurements.

The dental examination was conducted by

seven dentists employed at various times during

the survey. The examiners derived their findings

on a uniform basis by following as cIoseiy as

1
possible written, objective standards. The standards were guidelines which, in effect, narrowed

the range of examiner variability by eliminating

many borderline or questionable conditions that

are persistent sources of examiner disagreement.

To avoid procedures that might have introduced

systematic bias, the examining dentists were forbidden to dry or isolate teeth or to remove oral

debris and calculus. X-rays of the teeth were not

taken. An adjustable examining chair, a standard

light source, and a mouth mirror and explorer

were used during the examination. that usually

lasted about 10 minutes.

Definitions of dental conditions and procedures for conducting the examinations were

largely the same as those used during the Health

Examination Surveys of adults during 1960-625

and of children during 1963 -65.6 The same two

dentists who trained new examiners during both

previous surveys also trained those for the survey of youths and periodically reviewed their

findings. Hence, there is reason to believe that

the findings collected on both adults and children are comparable with those obtained on

youths. In addition, a comparison of the findings from replicate dental examinations (appendix I) suggests that interexaminer variability was

reasonably well controlled and did not seriously

bias the PI findings, Appendix I contains a description of the training and calibration of

examiners.

Nonresponse

At the close of the survey, 90 percent (or

6,768) of the 7,514 sample youths had been examined. Although data pertaining to the dental

conditions of the 746 nonrespondents are not

available to the survey staff, it is assumed that

nonresponse did not seriously bias the estimates

contained in this report. The national sample

and the examined group are closely representative of the 22.7 million noninstitutionalized

youths 12-17 years of age in the United States

with respect to age, sex, race, region, population

size of place of residence, and rate of population

change in size of place of residence from 1950

to 1960. (See appendix Ii--for definitions of demographic and socioeconomic terms.)

Limitations of Data

Several limiting factors need to be consiclcrcd

when using the data contained in this report.

The target population did not include institutionalized persons nor did it includc pm-sons residing on lands reserved for American Inclians.

Hence, a portion of the U.S. population that

may contain a high degree of dental morbidity is

not represented in these data. Another c{msicleration is that these data mc based on a sample

of the target population; therefore, the cstim~ttcs

are subject to sampling error. Sampling errors

are prominently displayed in tables 6-10. In this

report, sampling error has been taken into account by the use of statistical tests of si~nificance, as specified in appendix III.

PERIODONTAL INDEX (Pi)

The prevalence and severity of periodontal

disease among U.S. youths were measured by

the Periodontal Indexl (PI). The PI scores mch

tooth in the mouth, provided it is not u rout,

according to the presence and severity l~f periodontal disease. A score of O is assi~cd when no

indication of disease is found. If a portion of the

free gingiva is inflamed, a score of 1 is assikmcd.

If completely circumscribed by inflammation,

the tooth is scored 2. Teeth with overt pcrioduntal pockets are scored 6 if their mmtica[ory

function is unimpaired and 8 if it is impaired.

An individual’s PI is the arithmetic average of all

scores. The PI ranges from 0.0 (no inflammation

or pockets) to 8.0 (all teeth with pockets and

impaired function).

PERIODONTAL INDEX FINDINGS

Table A shows the estimated number and percent distribution of U.S. youths agccl 12-17

years, by status of periodontal disease. As classified by the Periodontal Index (PI), an estimated

15.4 miIlion youths, or about 68 percent,

showed a positive indication of periodontal disease. Of those with disease, 14.1 million had gingivitis (inflammation of the gums), and 1.3 milIion had destructive disease with obvious pocket

formation. The remaining 7.3 million youths

had no manifest sign of periodontal disease.

2
Table A. Estimated number and percent distribution of youths

aged 12-17 years, by periodontal status: United States,

1966-70

Number Percent

Status of periodontal disease of youths in distrithousands bution

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

Without periodontal disease . . . . . . .

With periodontal disease . . . . . . . . .

Wthoutpockets . . . . . . . , . .

With pockets . . . . . . . . . . . .n

22,679 100.0

7,274 32.1

15,405 67.9

14,077 62.1

1,328 5.8

Although about 7 out of every 10 youths

were classified m having periodontal disease, relativc’ly few had the severe form of the disease

(table I). Nearly half the youths (47.7 percent)

had PI scores of 0.1 or less, 69.7 percent had

scores of less than 0.4, and 82.4 percent had

scurcs less than 0.6. The concentration of low PI

scores und, as noted previously, the small percent (5.8) of youths with destructive disease evident suggest that periodontal disease is not an

imrnincnt threat to the oral health of most

y(”ruths.

The PI was designed for epidemiologic use,

and it is both rapid and simple to apply. It is

also :L relatively objective method of classification that makes it especially suitable for

cpidmniologic surveys. But even though the PI

do~’s not classify periodontal disease by clinical

critcri:t, specified ranges of the index among

iidults hiwe been found to correspond generally

with various clinical stages of gingivitis and

clm mic destructive disease. The relationship is

d~’scribed by Russell as follows:

Must pcrscms considered to be normal, clinically, score from

zero to 0.1 or 0.2; those with 3 clinical diagnosis of gingivitis,

[mm 0.1 to 1.0; those with severe gingivitis to incipient destructive disc~sc, from 0.5 to 1.9; those with frankly established destructive disease, from 1.5 to 5.0; and those with

disc.w in t;minal stages from about 4.0 to 8.0, the maximum score.

R:mges of the PI and their corresponding clinicul stages have not been established for youths.

Nevertheless, periodontal disease in U.S. youths

may be described as generally ranging from mild

to severe gingivitis, with little indication of destructive disease.

Although relatively small differences in the PI

are not usually si~ificant clinically, they may

nevertheless indicate variations in the prevalence

and distribution of periodontal disease that may

be significant epidemiologically. In.the following

sections, differences that are statistically significant are cited even though such differences are

not necessarily clinically significant.

Age

The mean PI for all youths aged 12-17 years

was 0.31 (table 2). Although the increases in

mean PI between successive years of age are not

statistically significant, the mean PI nevertheless

appears to increase slightly with advancing age

and is significantly greater among older than

among younger youths. The mean PI for

12-year-old youths (0.27) was substantially less

than that for 17-year-olds (0.36). Also, the mean

PI for 12-year-olds was significantly less than

that for both 15- and 16-year-old youths. The

relationship between age and mean PI is graphically illustrated in figure 1.

0.40

r 0.36

0.27

0.33 0.33

0.28

----

12 13 14 15 la 17

AGE IN YEARS

Figure 1. Average Periodontal Index for youths by age: United

States, 1966-70.

3
The national estimates in table 2 also show SeX

that there is a direct relationship bet~veen periodontal disease and age among Negro youths.

The mean PI for 12-year-old Negro youths was

significantly lower than that for Negro youths of

every other age except for those 13 years old.

Among white youths, on the other hand, the

mean PI did not increase significantly with advancing age (figure 2). Thus the weak association

of PI with age found among youths of all races

appears to be primarily a reflection of that same

association among Negro youths.

The mean PI for girls (0.30) of all races was

not materially different from that for br.lys

(0.33). In addition, the mean indexes for boys

and girls within any of the age groups did nf]t

differ significantly. Similarly, the mean PI for

white girls was not different from that for white

boys nor was that for Negro girls different from

that for Negro boys. Regardless of age or race,

there was no essential difference between the

mean PI of male and female youths.

0.60-

0.50-

xw

9

~ o.~oz

o

la

o

z

w

n

w

c1

0.30-

$

w

>

<

0.20

0.10

0.00[

12

❑ White

Negro

0.50

0.47

0.29

13

0.68

055

0.34

14 15

AGE IN YEARS

16 17

Figure 2. Average Periodontal Index for youths by race and age: United States, 1966-70.

4
Race

Nc~r( ) yuLtths had substantially more peri-

{)d(jnt:~l cliscase than white youths. The mean PI

ft~r all Negro youths (0.46) was si~ificantly

KIL.l[CT th:m thfit for ull white youths (0.29). In

.dditil]n, both Negro boys and girls had signifiu,tutly hi~her mean PI than white youths of the

s.(nlc sex: the index for Negro boys was 0.45 as

C{~mpared with 0.31 for white boys, and that for

NLHrCJ~ids ~vas 0.48 as compared with 0.28 for

}tthitc girls (t:tblc 2). Diffcrenccs in the periodont;il status of tvhitc and Negro youths were also

f(]und an]onS youths of the same age. Within

ft )ttr of the six tige groups, Negro youths had

sixnific;u-tdy hishcr mc:m indexes than did white

y[luths (fi~wrc 2). Thus the mean PI of Negro

y{ juths Jvas materially higher than that of white

youths regardless of their age or sex.

Expected (Age-Control) Value

In (Jrdcr to c{~ntrol for age, we introduce the

Cxpcclccl value. Since the foregoing estimates indic:itc that age is related to mean PI, an adjustment was mtide for diffevenccs in the age distributi~)n i~f the youths within each income and

cduc:iti[m group by calculating an expected

ViIILIC. In the “Income” and “Education” secti(ms of this report, a comparison of mean actual

Lmcl mc;m expected values for the age range

12-17 ymrs was used instead of a comparison of

nwun :tgc-specific values. Sampling variability for

spccillc age h-ywups was usually larger than for

the tt~t:d agc span owing to the smaller number

~]f s; Implc ytluths at each age. It is hecallse the

l;ir~cr swnp]ing variability for age-spl. ~,fic groups

frequently masks the relationship which exists

with respect to socioeconomic variables that the

summary comparison (actual-expected) was used

here instead of mean age-specific comparisons.

Expected values were calculated by weighting

:Igcwpccific mean PI for the total U.S. population of youths by the number of youths in each

.tgc gq-oup within specified ranges of a given demogr:tphic variable, such as family income. Actual and expected values may differ by chance,

but when the difference between them is statistically significant, one may conclude that the ac-.

tual mean PI of a given demographic group is

excessively larger or smaller than the mean of

that group for the United States and that the

excess is not attributed to age.

Income

The amount of yearly income earned by a

family was inversely associated with the occurrence of periodontal disease among youths. As

illustrated in figure 3, the mean PI for youths in

the lowest income group (less than $3,000) was

appreciably greater than that for youths in the

higher income groups. For example, youths

whose families earned less than $3,000 per year

had a mean PI of 0.49, but youths whose families earned $15,000 or more per year had a

mean PI of only 0.21 (figure 3, table 3).

When age was taken into consideration by

comparing mean actual with mean expected values. the inverse relation between mean PI and

Family income continued to be evident. For in0.50 r

0.49

0.40

0.35

0.27

0.21 0.21

Less than $3,000- $5,000- $7,000- $10,000- $15,OOO

$3,0W $4,999 $6,999 $9,999 $14,999 or more

FAMILY INCOME

Figure 3. Average Periodontal Index for youths aged 12-17 years

by family income: United States, 1966-70.

5
stance, youths whose families earned less than

$3,000 per year had a substantially higher mean

PI than expected, whereas youths whose families

earned $15,000 or more had a mean PI substantially lower than expected (figure 4).

The association of mean PI and family income

for white youths was similar to that for youths

of all races. As among all races, the mean PI for

white youths varied inversely with family income (figure 5). The mean PI of white youths

whose families earned $15,000 or more was substantially less than that for white youths whose

families ‘earned less than $3,000 (t’able 3, figure

I 0.17

0.09

0.04

1

I

.0.11 -0.11

-0.,5 ~

Lessthan $3,000- $5,00U- $7,000.$10,OLW s15,m

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

FAMILY INCOME

Figure 4. Difference between actual dnd expected average%rk

odontal Index (P1 ) for youths aged 12-17 years by family

income: United States, 1966-70.

0.60

0.40

z 0.30

n

~

~

z

o

n

Q o.m a

w

n

u

u

~

w

>

< 0.10

0.0+3

0.49

0.37

0.33

0.27

0.21 0.21

Lessthan $3,000- $5.000- $7,000. $10,CKIO S15,000

S3SKm $4,999 S6,999 S9,999 $14,999 or more

FAMILY INCOME

Figure 5. Average Periodontal Index for white youths aged 12-17

years by family income: United States, 1966-70.

0.50

0.40

x

u

~

< O.zn

+

z

o

n

o

E

I.#

~ o.m

5

z

0.10

0.00

0.49 -.-

U.*O

0.46

0.34

0.33

0.22

Lessthan $3,000. $5,000- $7,000. $10,000. $15,0MI

$3,0cd $4,999 S6:~ S9,999 $14,999 or more

FAMILY INCOME

Figure 6. Average Periodontal Index for Negro youths aged

12-17 years by family income: United States, 1966-70.

6
~). An age control JVaS not applied to white

y,,llths in this and the following sections, since it

IV;LS previously determined that mean PI of

white yuuths \vas essentially independent of age.

similarly, sex specifics are not discussed in this

report, hccauw no relationship between mean PI

;mcl sex was noted.

The mean PI of Neg~o youths also varied in-

\Lmcly ~vith family income. Negro youths in

lim ilics with an annual income of less than

$;3,[I[I0 h;td a higher mean PI than those in each

I)f the hi~hcr income groups (figure 6). After

L“(JLItII)lliIl~ fOr age, the weak association bet~vccn pmiodontal disease and Family income

mmtinucd to bc evident to the extent that Negro

y( luIhs in the two highest income groups had

appreciably less periodontal disease than expected (table 3).

Education

The estimated actual and expected mean PI of

youths according to sex, race, and educational

attainment of head of household are shown in

table 4. The education of parents was inversely

associated with periodontal disease of adolescents. PI decreased from a high of 0.61 for

youths whose parents had Icss than 5 years of

education to a low of 0.16 for those whose parents had 17 years or more of education (figure

7). After allowances were made for differences

in age, the inverse relation continued to be eviNone or

less than

5 years

0.61

0.35 0.36

0.25

0.18

5-7

years

8 years

EDUCA

9-11

years

TION OF HEP

12 years

!0 OF HOI

13-15

years

USEHOLD

16 years

0.16

1

17 years

or more

Flqure 7. Average Periodontal Index for youths of all races aged 12-17 years by education of head of household: United States,

1966-70.

7
dent. For example, the mean PI of youths whose

parent or guardian had less than 5 years of education was greater than expected, while that for

those whose parents had 17 years or more of

education was appreciably less than expected

(figure 8).

Since there are appreciably more white than

Negro youths in the United States, findings for

all races reflect, to a great extent, the findings of

white youths. Thus, as noted for all youths, the

mean PI for white adolescents was inversely associated with the educational achievement of

their parents (figure 9). Mean PI decreased from

a high of 0.61 for white adolescents whose parents had less than 5 years of education to a low

of 0.16 for those whose parents had 17 years or

more of education.

For Negro youths, the mean PI did not appear

to be related to their parents’ educational status.

For instance, the mean PI for Negro adolescents

whose parents had less than 5 years of education

Negro youths whose ptirents had more formal

education. After controlling for age, no rclatl{]n

between PI and education of head of household

appeared among Negro adolescents.

Region

The mean PI for youths of all races (table 5)

was substantially higher in the South (0.39) than

in the West (0.29) and Midwest (0.26). After

accounting for age, the mean PI of youths in the

South remained higher than that (.tf yuuths in

the West and Midwest.

As for youths of all races, Negro adolescents

residing in the South had an appreciably ~gmatcr

mean PI (0.56) than did those in both the West

(0.28) and Midwest (0.35). After age diffc,enccs

were considered, the mean PI of Negro youths in

the South continued to be higher than that of

Negro youths in the West and Midwest. ‘1’hc estimates for white youths did not differ significantwas no; appreciably different from that of other ly for any region.

0.30

0.11

1

0.03 0.04

I!iiK

-0.06 I

-0.13

-0.20I I I I I I 1 I J

None or 5-7 8 years 9.11 12 years 13.15 16 years 17 years

less than years years years or more

5 years

EDUCATION OF HEAO OF HOUSEHOLD

Figure 8. ~~ifferencesbetween actual and expected average Periodontal Index (Pi) for youths aged 12-17 years by educetion of head of

household: United States 1966-70.

8
0.70 ~

0.60

0.50

0.40

0,30

0.20

0.10

0.00

0.61

0.33

Nme cm

less than

5 years

5-7

years

8years 9-11 12 years 13-15

years years

EDUCATION OF HEAD OF HOUSEHOLO

16 Veam

0.16

I

17 years

or more

Fqure9. Average Periodontal lndexfor white youths aged 12-17 years by education of head of household: United States, 1966-70.

DISCUSSION

Interrelation of PI and Selected

Demographic Variables

The interrelation of PI and selected demogmphic chwxteristics may be further assessed

by the st;itistkal method of correlation analysis.

By this tmthod, the relative strength of the associ~ltion of selected variables (age, race, income,

and educ:ttion) with PI are quantified separately

by calculating simple correlation coefficients.

The simple correlation coefficients shown in table B indicate that age, race, family income, and

education of head of household are related, in

varying degrees, to periodontal disease. These

correlations would be expected since the mean

PI was previously shown to be related to age,

race, income, and education. Further insight

into the relationship of the variables with periodontal disease may be obtained from the partial correlation coefficients in table B which

quantify the correlation between each variable

and periodontal disease when the associations

between the other variables and PI are held constant.

Thus, when the association among periodontal disease and age, income, and education are

9
Table B. Correlation coefficients and standard errors between the Periodontal Index and selected variables: United

States, 1966-70

Selected variables

Age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Race . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..s . .

Family income . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Education ofhead ofhousehold. . . . . . . . . . . . . . . . . . . . . . . . . .

held constant, the correlation between periodontal disease and race becomes insignificant.

Hence, the association between race and periodontal disease is largely accounted for by differences in income and education.

Income and education have been shown tobe

associated with periodontal disease. However,

family income isalsohighly correlated titheducation (r= 0.56). Two questions now arise:

First, is education independently associated with

the Periodontal Index, or is the association due

to the correlation between income and education? Second, is income independently associated with the Periodontal Index, or is the association a reflection of the correlation between education and income?

With income, race, and age held constant, the

partial correlation between education and the

Periodontal Index is substantially different from

zero. The partial correlation between income

and the Periodontal Index is also significantly

different from zero when the effects of education, race, and age are held constant. It would

appear that both education and income are independently associated with periodontal disease.

PI Findings From Previous HES Reports

The national estimates in this report bring to

completion an epidemiologic description of the

occurrence of periodontal disease in the noninstitutionalized, civilian U.S. population aged

6-79 years. The first report that contained national estimates for a major segment of the Nation’s population described the occurrence of

Correlation coefficierits and standard errors

Simple

Standard

error

I

.06 .014

.12 .041

-.21 .019

-.22 .024

Partial for standard

5-variable

T

error

equation

.06 .015

.05 .045

-.09 .022

-.12 .023

periodonta~ disease amen{ adults aged 18-79

years (1960 -62).8 The second one contained estimates for children aged 6-11 years ( 1963-65) 6

The mean PI scores for the successive age ~woups

in all three surveys are shown in table C.

The periodontal findings for children, youths,

and adults are believed to be comparable, largely

because the training and supervision of the exam ining dentists were essentially the same

throughout the three surveys. It should be

pointed out, however, that the data on which

the estimates are based were collected during

different years, and it is not known whether the

periodontal status of the population changed appreciably during the period that began in 1960

at the start of the adults’ examinations and

ended in 1970 at the close of the youths’ examinable C. Average Periodontal Index {PI) for children, 1963-65;

youths, 1966-70; and adults, 1960-63, by age: United States

Age Mean PI

Children,6-l l years . . . . . . . . . . . . . . . . . . 0.13

Youths, 12-17 years . . . . . . . . . . . . . . . . . . 0.31

Adults, 18-79 years . . . . . . . . . . . . . . . . . . 1.13

18-24 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.54

25-34 vaars . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.75

35-44 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.04

45-54 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.42

55-64 years . . .. . . . . . . . . . . . . . . . . . . . . . . . . . 1.84

65-74 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.05

75-79 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.92

10
niitions. Nonetheless, it seems reasonable to assume that any change in periodontal status that

might have occurred, especially among children

and youths, was minimal.

The average score per person for children,

youths, and adults is shown according to single

year of age in table D. The upward trend with

increasing age suggests that the relationship of PI

with age approximates a linear one. In addition,

the uptrend is fairly smooth, suggesting that the

estimates for the three population segments are

comparable for all practical purposes.

The qualitative changes that occur in periodcmt:il disease with advancing age are indicated

in table E. The percent free of overt signs of

gingival and periodontal disease decreased from

(i 1.3 for children to 32.1 for youths and to 26.1

for adults. The percent with inflamed gums but

without periodontal pockets increased from

37.9 for children to 62.1 for youths and then

dccreascd to 48.5 for adults. The smaller percent

Table D. Average Periodontal Index (P1) for children, 1963-65;

youths, 1966-70; and adults, 1960.63, by single year of

age: United States

Age

Children, 6-n years . . . . . . . . . . . . . . . . . .

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

7 years, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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

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

10years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

11 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Youths, 12-17 years . . . . . . . . . . . . . . . . . .

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

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

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

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

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

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

Adults, 18-24 years . . . . . . . . . . . . . . . . . .

18 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

19years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

20years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

21 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

22years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

23years .,,...,..,.,,.....,,. . . . . . . . . .

24years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Mean PI

0.13

0.07

0.11

0.13

0.15

0.14

0.16

0.31

0.27

0.28

0.32

0.33

0.33

0.36

0.54

0.36

0.51

0.62

0.44

0.61

0,66

0.57

of adults than of youths with gingivitis resulted

from the rapid increase intheprevalence of destructive periodontal disease among older adults.

For instance, the percent with periodontal

pockets increased from 0.8 for children to 5.8

for youths and finally to 25.4 for adults. Furthermore, the percent of adults with pocket formation rose steadily from a low of about 10 for

those aged 18-24 years to a high of about 55 for

those aged 75-79 years. Clinically, the picture is

one in which, on the one hand, the prevalence

and seventy of gingivitis rise rapidly during adolescence and, on the other hand, the prevalence

and seventy of chronic destructive disease rise

rapidly during adulthood.

The association of PI with selected demographic characteristics prevailed consistently

during childhood, adolescence, and adulthood in

some instances but not in others. For example,

scores rose with age more consistently among

white than among hTegro children; whereas during adolescence only the scores of hTegro youths

showed upward trends with age. By contrast, the

PI of both white and Negro adults increased

sharply with advancing age.

Table E. Percent distribution of children, 1963-65; youths,

1966-70; and adults, 1960-63; by status of periodontal

disease and age: United States

1

Status of periodontal disease and age I

Percent

distribution

U.S. children, 6-11 years . . . . . . . . . .

w

Without periodontal disease . . . . . . . . . . . . . . 61.3

With periodontal disease . . . . . . . . . . . . . . . . . 38.7

Without pockets . . . . . . . . . . . . . . . . . . . . 37.9

With pockets . . . . . . . . . . . . . . . . . . . . . . 0.8

U.S. youths, 12-17 years . . . . . . . . . . . .

r

100.0

Without periodontal disease . . . . . . . . . . . . . . 32.1

With periodontal disease . . . . . . . . . . . . . . . . . 67.9

Without pockets . . . . . . . . . . . . . . . . . . . . 62.1

With pockets . . . . . . . . . . . . . . . . . . . . . . 6.8

U.S. adults, 18-79 years . . . . . . . . . . . . .

r

100.0

Without periodontal diseases . . . . . . . . . . . . . . 26.1

With periodontal diseases . . . . . . . . . . . . . . . . 73.9

Without pockets . . . . . . . . . . . . . . . . . . . . 48.5

With pockets . . . . . . . . . . . . . . . . . . . . . . 25.4

11
The association of PI with sex and race also

differed during the three stages of growth and

development. Mean scores for children and

youths did not differ by sex, but mean scores

for men were consistently higher than those for

women of comparable age. Further, scores were

not associated with race among children, but

scores for Negro youths and adults were consistently higher than those for white youths and

adults of comparable age and sex.

By contrast, the inverse association of PI with

family income and education (both the adults’

own and that of the children’s and youths’ parents) prevailed among all three age ranges of the

population. In addition, mean periodontal scores

per person were significantly higher for those

children and youths of all races living in the

South than for those living in the Midwest and

West.

As indicated in table E, significant qualitative

changes occurred in periodontal disease with advancing age. The PI measures only quantitative

changes, which for youths aged 12-17 years and

also for children 6-11 years of age were usually

so, slight that they gave no clinical significance.

Thus the association of PI with a demographic

characteristic must be a relatively strong one to

persist during childhood, adolescence, and

adulthood.

The Oral Hygiene Index and its relation to PI

and various demographic characteristics are not

included in this report.

SUMMARY

The data presented in this report are national

estimates from the Division of Health Examination Statistics survey of youths in 1966-70. A

probability sample of 7,514 adolescents in the

civilian, noninstitutionalized population was scientifically selected to represent the Nation’s

youths 12-17 years of age. Of these, the 6,768

examined youths (or 90 percent of the sample)

were closely representative of the Nation’s adolescent population with respect to age, race, region of residence, family income, and parent education. The prevalence and severity of

periodontal disease were measured by Russell’s

Periodontal Index.

Periodontal disease, although quite prevalent

among the adolescents of the United States, is

not usually severe in this group. Approximately

68 percent of the Nation’s youths had some visible sign of periodontal disease, but the abundant

number of youths with low PI scores und the

relatively small proportion of youths with clcstructive disease indicate that periodontal disease, when present, was usually mild.

The average PI for all youths aged 12-17 years

was 0.31. Periodontal disease increases slightly

with advancing age, rising from 0.27 for 12-ycarolds to 0.36 for 17-year-olds. Similarly the mean

PI for Negro adolescents was directly associated

with age; but among white adolescents, periodontal disease does not increase significtintly

with advancing age.

The prevalence of periodontal disease is similar among boys and girls, regardless of agc or

race. The mean PI for girls (0.30) of all races was

not materially different from that of buys

(0.33). In addition, within any of the agc groups

the mean PI for boys did not differ significantly

from that of girls. The mean PI for white boys

was not different from that of white girls nor

was that for NTegro boys different from that of

Nego girls.

Significant differences in periodontal discmc

were found by race. The mean PI for all Ne,qro

youths (0.461 was significantly greater thtin thut

for all white youths (0.29). Both TTcgro buys

and girls had materially higher mean indexes ,

than white adolescents of the same sex. Within

the same age group, Negro adolescents usLadly

had appreciably higher mean scores than did

white youths.

The difference observed in periodontal diwasc

by race was attributed primarily to diffcrcnc’cs

in family income and education. With both income and education held constant, the partiid

correlation between race and the Periodontal Index was not materially different from O. I Iencc,

the association between race and periodontal

disease is largely accounted for by differences in

income and education.

Periodontal disease, as measured by the Periodontal Index, is inversely related to income.

Among the adolescents of all races, for example,

the mean PI of youths in families with an income of less than $3,000 per year was 0.49, but

those in families with an income of $15,000 per

year or more had a mean PI of 0.21.

As with family income, education of parents

was inversely associated with mean PI of adolescents. This was not unexpected since income

12
edumtion are highly correlated. However, it

ulso found that income and education were

independently associated with periodontal

discusc.

Rcg;wdkss of tigc, the mean PI for youths was

higher in the South than in the West and hIid.

west, Similarly, Negro youths in the South had a

higher mean PI thun Negro youths in the West

ancl hlidwest. The estimates of PI scores for

white youths did not differ materially among

the regions.

A comparison of this report’s findings with

the findings of Health Examination Surveys of

children in 1963-65 and of adults in 1960-62 is

included in this report. The comparison shows a

similar association of PI with demographic characteristics, particularly family income and education, during childhood, adolescence, and

adulthood.

REFERENCES

I R1,~x{.ll, A, L.: A Systcrn of classification and scoring for

prw,,lencr .urwys o! pmiodontA disease. j. Dent. Re.r. 35(3):

:{!w-:{rl!l,.lunc 1956.

2N.iti,,n,ll Center for Ik.dth Statistics: Plan und opemtion of a

Ik.(lth Ex.imirmticm Survey of U.S. youths 12-17 years of age.

i’it,tl (lndHtwlth .Statiitic.v. PHS Pub. No. 1000-Series 1-No. 8.

Public Ikaith Service. W’mhington, U.S. Government Printing

CWlice, Sept. 196!1,

‘{N.ttil~n;tl Center for Health Statistics: Cycle I of the Hvalth

ft~,tmin.itirm Surwy, wmpk and response, United States,

1!l(i(+~iU. l~iful and H,wlth Statisi%cs. PHS Pub. No. 1000-Series

1l-Ntl. 1. Public Health Service. Washington. Government Printing Of’fhx, Apr. 1964.

4National Center for %dth Statistics: Pkm, opemtion, and

rcsponw rcwlts of ,t program of children’s examinations. Wtat

([ml H{with Stut/sties. PHS Pub. No. 1000-Series 1-No. 5. Public

1Ic.;ltb Scrvkc. \Vashington. U.S. Government Printing Office,

OK!. 1967,

5N.\tinn:d Center for Health Smtistics: Selected dentd findinhwin ;idults by age, race, and sex, United States, 1960-1962.

vital and Health Stati~tic~. pHS pub. No. 1f)fJf).Serie~ 11.NcI. 7.

Public Health Service, Wmhkgton. U.S. Government Printing

Office, Nov. 1965.

6Nationaf Center for Health Statistics: Periodontal disease and

oral hygiene among children, United States. Vital and Health

Statistics. Series 1l-No. 117. DHEIV Pub. No. (HSM)7Z-106O.

Heafth Services and Mental Health Administration. Washington.

U.S. Government Printing Office, June 1972.

7Russell, A. L.: Some epidemiological characteristics of periodontal dkease in a series of urban populations. ./. Periodo rrt.

28:286-293, Oct. 1957.

8Nationa1 Center for Health Statistics: Periodontal flsease

among adults, United States, 1960-1962. Vital and Heulth Statktics, PHS Pub. No. 1000-Series 11-No. 12. Public Health Service.

tVashington. U.S. Government Printing Office, Nov. 1965.

‘National Center for Health Statistics: Pseudoreplication, further evaluation and appfkation of the balanced h~f-sample technique. Vital and Health Statistics. PHS Pub. No. 1000-Series

2-No. 31. Public Health Service. Washington. U.S. Government

Printing Office, Jan. 1969.

000

13
LIST OF DETAILED TABLES

Table 1.

2.

3.

4.

5,

6.

7.

8,

9.

10,

Number and percent distribution of youths aged 12-17 years, by Periodontal Index and sex: United States,

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

Average Periodontal Index foryouths, byrace, sex, and age: United States, 1966-70 . . . . . . . . . , . . . . .

Actual and expected average Periodontal Index for youths aged 12-17 years, by sex, race, and family

income: UnitedStates, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Actual and expected average Periodontal lndexfor youths aged 12-17years, bysex, race, and education of head of

household: UnitedStates, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Average Periodontal Index for youths aged 12-17 years, by sex, race, and geographic region: United States,

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

Standard errors of estimates of the number and percent of youths aged 12-17 years, by Periodontal Index and

sex: UnitedStates, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . , . . . . . . . . . . . . , ,

Standard errors of estimates of the average Periodontal Index for youths, by race, sex, and age: United

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

Standard errors of estimates of the average Periodontal lndexfor youths aged 12-17years, bysex, race, and family

income: UnitedStates,1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Standard errors of estimates of the average Periodontal Index for youths aged 12-17 years, by sex, race, and

education ofhead of household: United States, 1966-70 . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . .

Standard errors of estimates of the average Periodontal Index for youths aged 12-17 years, by sex, race, and

geographicregion: UnitedStates, 1966-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Page

15

15

16

17

18

18

19

19

20

20
TaLIlcl Numtw and percent distribution of youths aged 12-17 years, by

Pcr,adonral lndox andsex: Unmed States, 1966.70

P+:riudcmtal Index !Elk_k

Number m thouwtd$’

!2,679 11,476

7,274

3,536

2,643

2,340

1,706

1,180

780

585

581

382

272

25s

152

139

136

140

90

70

68

53

61

34

19

31

20

21

3

14

s!

6

7

71

3,507

1,609

1,340

1,149

9S6

6s4

464

336

313

226

188

126

72

77

77

61

45

35

43

24

30

11

13

13

3

3

7

5

4

2!5

11,203

.

3,767

1,927

1,304

1,191

719

495

316

250

268

156

83

132

81

62

5s

7E

4!

3e

2!

26

31

2;

E

lf

1[

lE

f

4f

Both IIBcws Girls

sexes

II I

Percent dwtribution

I 00.0

_

32.1

15.6

11.7

10.3

7.6

5.2

3.4

2.6

2,6

1.7

1.2

1.1

0.7

0.6

0.6

0.6

0.4

0,3

0,3

0.2

0,3

0.2

0.1

0.1

0,1

0.1

0.0

0.1

0.0

0.0

0.0

0,3

—

00.0

30.6

14.0

11.7

10.0

8.6

6.0

4.0

2.9

2.7

2.0

1.6

1.1

0.6

0.7

0.7

0,5

0.4

0,3

0.4

0,2

0.3

0.1

0,1

0.1

0.0

0.0

0,1

0.1

0.0

0.2

100.0

33.6

17.2

11.6

10,6

6.4

4.4

2.8

2.2

2.4

1.4

0.7

1.2

0.7

0.6

0.5

0.7

0.4

0,3

0.2

0.3

0.3

0.2

0.1

0.2

0,2

0.2

0.0

0.1

0,0

0.1

0.0

0.4

Table2. Average Periodontal Indaxfor youths, byrace, sex, and

age: United States, 1966-70

Sex and age

Both sexes

Total, 12-17 years . . . . . . . .

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

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

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

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

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

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

Boys

Total, 12-17years . . . . . . . .

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

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

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

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

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

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

Girls —

Total,12-17years . . . . . . . .

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

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

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

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

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

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

0.31

0.27

0.28

0.32

0.33

0.33

0.36

0.33

0.28

0.29

0.34

0.35

0.33

0.37

0.30

0.25

0.28

0.30

0.32

0.34

0.34

0.29

0.27

0.27

0.29

0.31

0.30

0.31

0.31

0.27

0.28

0.32

0.33

0.30

0.33

0.28

0.26

0.26

0.26

0.29

0.30

0.29

0.46

0.29

0.34

0.50

0.47

0.55

0.68

0.45

0.35

0.31

0.46

0.43

0.54

0.66

0,48

0.23

0.3B

0.55

0.51

0.56

0.70

Ilncludes data for “other races,” which are not shown

separately.

15
Table3. Actual and expected average Periodontal Index for youths aged 12-17 years, bysex, race, and family income: United States,

1966-70

Race and family income

All races’

Lessthan $3,000 . . . . .

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

$5,000-$6,999 . . . . . . .

$7,000-$9,999 . . . . . . .

$10,000-$14,999 . . . . .

$15,1100 or more . . . . .

Unknown . . . . . . . . . .

White

Lessthan $3,000 . . . . .

$3,000-%)999 . . . . . . .

$5,000-$6,999, . . . . . .

$7’000-$9,999 . . . . . . .

$1 (),0(3().$14,999 . . . . .

$15,000 or more . . . . .

Unknown . . . . . . . . . .

Negro

Lessthan $3,000 . . . . .

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

$5,000-$6,999, . . . . . .

$7,000-$9,999, . . . . . .

$10,000-514,999 . . . . .

$15,000 or more . . . . .

Unknown . . . . . . . . . .

Actual

0.49

0.40

0.35

0.27

0.21

0.21

0.37

0.49

0.37

0.33

0.27

0.21

0.21

0.33

0.49

0.48

0.46

0.34

0.33

0.22

0.68

Both sexes

Expected

0.32

o.3f

0.31

0.31

0.32

0.32

0.32

0.29

0.29

0.29

0.29

0.29

0.29

0.29

0.47

0.46

0.46

0.46

0.49

0.49

0.48

Difference

0.17

0.09

0.04

-0.04

-0.11

-0.11

0.05

0.20

0.08

0.04

-0.02

-0.08

-0.08

0.04

0.02

0.02

0.00

-0.12

-0.16

-0.27

0.20

Actual

0.55

0.36

0.35

0.28

0.23

0.21

0.35

0.55

0.36

0.35

0.28

0.23

0.21

0.35

0.47

0.51

0.46

0.31

0.33

0.31

0.45

Boys

Expected

0.33

0.33

0.33

0.33

‘3.33

0.33

0.33

0.31

0.3?

0.31

0.31

0.31

0.31

0.31

0.46

0.44

0.44

0.45

0.45

0.50

0.47

Difference

0.22

0.03

0.02

-0.05

--0.10

-0.12

0.02

0.24

0.05

0.04

-0.03

-0.08

-0.10

0.04

0.01

0.07

0.02

-0.14

-0.12

-0.19

0.02

Actual

0.45

0.39

0.34

0.26

0.19

0.20

0.38

0.43

0.38

0.32

0.25

0.18

0,20

0.29

0.50

0.45

0.46

0.40

0.33

0.14

0,88

Girls

Expected

0.30

0.30

0.30

0.30

0.30

0.31

0.37

0.28

0.27

0.27

0.28

028

0.28

0.28

0.48

0.48

0.47

0.46

0.52

0.49

0.49

)ifference

.—

0.15

0.09

0.04

-0.04

-0.11

-0.11

0.07

0.15

0.11

0.05

-0.03

-0.10

-0.08

0,01

0.02

-0.03

-0.01

-0.06

-0.19

-0.35

0,39

1Includes data for “other races,” which are not shown separately.

16
T.Iblc 4. Actual and expected average Periodcmtal Index for youths aged 12-17 years, by sex, race, and education of head of

household: United States, 1966-70

RJCPand education of

head of housphold

All racesl

Lossthan 5 years . . . ,

5-7yrwrs . . . . . . . . . . .

Elywms..<, . . . . . . . .

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

12ywm.... . . . . . . .

12-15 years . . . . . . . . .

113ycar s . . . . . . . . . .

17yctws or more . . . . .

Unknown . ...,.....

wLI’SSthan 5 years . . . . .

5-7 years . . . . . . . . . . .

8yt:dr s . . . . . . . . . . .

%lly ems. . . . . . . . . .

12ymr s . . . . . . . . . .

13-15 ywrrs . . . . . . . . .

ltiymr s . . . . . . . . . .

17years or more . . . . .

Unt.now n.......,..

N=

Lrssthan5yt?ars . . . . .

5-7vears . . . . . . . . . . .

13ycars . . . . . . . . . . . .

9-llycars . . . . . . . . . .

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

13.15 yetrrs . . . . . . . . .

lGyears . . . . . . . . . . .

17years or more . . . . .

Unknown . . . . . . . . . .

Actual

0.61

0.43

0.35

0.36

0,25

0.22

0.18

0.16

0.47

0.61

0.41

0.34

0.33

0.24

0.21

0.18

0.16

0.43

0.62

0.47

0.43

0.46

0.35

0.55

0.34

0.34

0.55

Both sexes

Difference

0.31

0.32

0.32

0.32

0.31

0.32

0,31

0.31

0.32

0,29

0.29

0,29

0,29

0.29

0.29

0.29

0.29

0,29

0.46

0.46

0.47

0.47

0.45

0.47

0.38

0.47

0.49

0.3(

0.11

0.0:

().0$

-ooof

-0.lc

-0.12

_o,l~

o.1~

0.32

0.12

0.05

0.01

-0.05

-0.08

-0.11

-0.13

0.14

0.16

0.01

-0.04

-0.01

-0.10

-0.12

-0.04

-0.13

0.06

Actual

0.69

0.47

0.35

0.35

0.26

0.24

0.21

0.15

0.46

0.70

0.46

0.33

0.33

0.25

0.23

0.22

0.15

0.46

0.66

0.49

0.47

0.44

0.28

0.39

0.20

0.30

0.45

Boys

Expected

0.33

0.33

0.33

0.33

0.33

0.32

0.32

0.33

0.33

0.31

0.31

0.31

0.31

0.31

0.31

0.30

0.31

0.31

0.44

0,44

0.45

0,46

0.43

0.45

0.40

0,50

0,48

Difference

0.36

0.14

0.02

0.02

-0.07

-0.08

-0.11

-0.18

0.13

0.39

0.15

0.02

0.02

-0.06

-0.08

-0.08

-0.16

0.15

0.22

0.05

0.02

-0.02

-0.15

-0.06

-0.20

-0.20

0.03

Actua

0.54

0.3s

0.34

0.3C

0.24

0.2C

(j.1~

0.7s

0.47

0.52

0.37

0.34

0.33

0.22

0.19

0.14

0.18

0.41

0.59

0.44

0.39

0.49

0.42

0.32

0.60

0.46

0.59

Girls

Expected

0.30

0.30

0.30

0.30

0.30

0.31

0.30

0.30

0.31

0.27

0.27

0.28

0.27

0.27

0.28

0.28

0.27

0.28

0.49

0.48

0.50

0.47

0.47

0.48

0.33

0.32

0.51

Difference

0.24

0.09

0.04

0.06

-0.06

-0.11

-0.15

-0.12

0.16

0.25

0.10

0.06

0.06

-0.05

-0.09

-0.74

-0.09

0.13

0.10

0.04

-0.11

0.02

-0.05

-0.16

0.27

0.14

0.08

] Includes data for “other races,” which are not shown separately.
Table5. Average Periodontal Index foryouths agad 12-17 years,

bysex, race, and geographic region: United States, 1966-70

Race and geographic region

All races’

Northeast . . . . . . . . . . . . . . . .

Midwest . . . . . . . . . . . . . . . . .

South . . . . . . . . . . . . . . . . . . .

West . . . . . . . . . . . . . . . . . . .

White

Northeast . . . . . . . . . . . . . . . .

Midwest . . . . . . . . . . . . . . . . .

South . . . . . . . . . . . . . . . . . . .

West . . . . . . . . . . . . . . . . . . .

Negro

Northeast . . . . . . . . . . . . . . . .

Midwest . . . . . . . . . . . . . . . . .

South . . . . . . . . . . . . . . . . . . .

West . . . . . . . . . . . . . . . . . . .

Both sexes

*

0.33

0.26

0.39

0.29

0,31

0.25

0.33

0.29

0.47

0.35

0.56

0.28 *

0.31

0.28

0.39

0.33

0.30

0.27

0.34

0.33

0.40

0.38

0.55

0.28

0.34

0.24

0.39

0.26

0.31

0.23

0.32

0.26

0.52

0.32

0.56

0.29

* Includes data for “!-xher races, ” which are not shown

separately.

Table6. Standard errors of estimates of thenumber and percent

of youths aged 12-17 years, by Periodontal Index and sex:

United States, 1966-70

Periodontal

Index

0.0 . . . . . . .

0.1 . . . . . . .

0.2 . . . . . . .

0.3 . . . . . . .

0.4 . . . . . . .

0.5 . . . . . . .

0.6 . . . . . . .

0.7 . . . . . . .

0.8 . . . . . . .

0.9 . . . . . . .

1.0 . . . . . . .

1.1 . . . . . . .

1.2 . . . . . . .

1.3 . . . . . . .

1.4 . . . . . . .

1.5 . . . . . . .

1.6 . . . . . . .

1.7 . . . . . . .

1.8 . . . . . . .

1.9 . . . . . . .

2.0 . . . . . . .

2.1 . . . . . . .

2.2 . . . . . . .

2.3 . . . . . . .

2.4 . . . . . . .

2.5 . . . . . . .

2.6 . . . . . . .

2.7 . . . . . . .

2.8 . . . . . . .

2.9 . . . . . . .

3.0 . . . . . . .

3.7 . . . . . . .

3.2 . . . . . . .

E!iEilE

Number

48C

179

15C

119

109

74

52

34

62

42

25

39

32

22

22

23

21

15

18

13

18

15

10

11

8

10

3

8

5

4

5

20

232

84

81

55

71

56

42

29

31

31

20

20

22

15

16

14

8

12

13

6

14

6

7

6

3

3

6

4

4

10

258

116

91

88

53

42

28

27

46

35

15

25

22

15

16

16

15

12

12

11

8

10

4

8

7

9

3

5

3

4

3

15

Percent

2.1

0.8

0,7

0.5

0.5

0.3

0.2

0.2

0.3

0.2

0.1

0.2

0.1

0.1

0.1

0.1

0.1

0.1

0.1

0.1

0.1

0.1

0.0

0,1

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.1

2.0

0.7

0.7

0.5

0.6

0.5

0.4

0.3

0.3

0.3

0.2

0.2

0.2

0.1

0,1

0.1

0.1

0.1

0.1

0.1

0.1

0.1

0.1

0.1

0.0

0.0

0.1

0,0

0.0

0.1

2.3

1.0

0.8

0.8

0.5

0,4

0.3

0.2

0.4

0.3

0.1

0.2

0.2

0.1

0.1

0.1

0.1

0.1

0.1

0.1

0,1

0.1

0.0

0.1

0.1

0.1

0.0

0.1

0.0

0.0

0.0

0.1

‘Includes data for “other races,” which are not shown

18
Table7. Standard errors of estimates of theaverage Periodontal

Index for youths, by race, sex, and age: United States,

1966-70

Sex and age

Both sexes

Total, 12-17 years . . . . . . . .

12yci3rs . . . . . . . . . . . . . . . . . . .

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

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

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

16ycars . . . . . . . . . . . . . . . . . . .

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

Boys

Total, 12-17years . . . . . . . .

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

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

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

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

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

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

Girls

Total, 12-17years . . . . . . . .

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

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

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

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

lGyears . . . . . . . . . . . . . . . . . . .

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

All

White

racesl

0.01 0.01

0.02 0.02

0.02 0.02

0.02 0.02

0.02 0.02

0.02 0.02

0.02 0.02

0.01 0.02

0.02 0.02

0.02 0.02

0.02 0.02

0.02 0.02

0.03 0.02

0.03 0.03

0.02 0.02

0.02 0.02

0.03 0.03

0.02 0.01

0.03 0.03

0,03 0.03

0.03 0.03

Negro

0.05

0.03

0,03

0.07

0.07

0.05

0.10

0.04

0.03

0.03

0.06

0.07

0.08

0.13

0.05

0.04

0.05

0.10

0.10

0.08

0.12

Table8. Standard errors of estimates of the average Periodontal

Index for youths aged 12-17 years, by sex, race, and family

income: United States, 1966-70

Race and family income

All races’

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

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

$5,000-$6,999 . . . . . . . . . . . . .

$7,000-$9,999 . . . . . . . . ...’..

$10,000-$14,999 . . . . . . . . . . .

$15,0000rmore . . . . . . . . . . .

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

White

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

!33,000-$4,999 . . . . . . . . . . . . .

S5,000-$6,999 . . . . . . . . . . . . .

$7,000-$9,999 . . . . . . . . . . . . .

$10,000-$14,999 . . . . . . . . . . .

$15,0000rmore . . . . . . . . . . .

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

Negro

Lessthan$3rO00 . . . . . . . . . . .

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

$5,000-$6,999 . . . . . . . . . . . . .

$7,000-$9,999 . . . . . . . . . . . . .

$10,000-$14,999 . . . . . . . . . . .

$15,0000rmore . . . . . . . . . . .

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

Both sexes

0.03

0.02

0.03

0.02

0.01

0.02

0.03

0.04

0.02

0.03

0.02

0.01

0.02

0.03

0.08

0.04

0.15

0.08

0.05

0.03

0.13

Boys

0.04

0.02

0.03

0.01

0.02

0.02

0.03

0.05

0.02

0.03

0.01

0.02

0.02

0.03

0.05

0.06

0.18

0.10

0.05

0.11

0.08

0.04

0.03

0.03

0.03

0.02

0.02

0.06

0.04

0.04

0.03

0.03

0.02

0.02

0.04

0.08

0.03

0.13

0.09

0.08

0.10

0.30

1 Includes data for “other races,” which are not shown

1Includes data for “other races,” which are not shown

w,parately.

19 .
Table9. Standard errors of estimates of the average Periodontal

Index for youths aged 12-17 years, by sex, race, and

education of head of household: United States, 1966-70

Table IO. Standard errors of estimates of the average

Periodontal Index for youths aged 12-17 years, bysex, race,

and geographic region: United States, 1966-70

Race and education of

head of household

All races’

None orlessthan5 years . . . . . .

5-7years . . . . . . . . . . . . . . . . .

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

9-n years . . . . . . . . . . . . . . . .

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

13-15years . . . . . . . . . . . . . . .

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

17yearsormore . . . . . . . . . . .

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

White

None orlessthan5 years . . . . . .

5-7years . . . . . . . . . . . . . . . . .

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

9-lljears . . . . . . . . . . . . . . . .

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

13-15years . . . . . . . . . . . . . . .

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

17yearsormore . . . . . . . . . . .

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

Negro

Noneorless than 5years . . . . . .

5-7years . . . . . . . . . . . . . . . . .

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

9-n years . . . . . . . . .. . . . . . . .

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

13-15years . . . . . . . . . . . . . . .

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

17yearsormore . . . . . . . . . . .

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

Both sexes

0.08

0.03

0.03

0.02

0.02

0.02

0.02

0.02

0.05

0.10

0.02

0.03

0.02

0.02

0.01

0,02

0.02

0.05

0.13

0.06

0.06

0.05

0.07

0.11

0.35

o.la

0.12

Boys

0.08

0.04

0.02

0.02

0.01

0.03

0.03

0.01

0.07

0.06

0.04

0.03

0.02

0.01

0.02

0.03

0.01

0.08

0.18

0.07

0.08

0.04

0.06

0.17

.0.23

0.16

0.20

iirls

0.11

0.03

0.04

0.04

0.02

0.02

0.02

0.03

0.06

0.15

0.03

0.04

0.04

0.02

0.02

0.02

0.03

0.07

0.11

0.08

0.06

0.08

0.09

0.13

0.77

0.36

0.11

Race and geographic region

All racesl

Northeast . . . . . . . . . . . . . . . .

Midwest . . . . . . . . . . . . . . . . .

South . . . . . . . . . . . . . . . . . . .

West . . . . . . . . . . . . . . . . . . .

White

Northeast . . . . . . . . . . . . . . . .

Midwest . . . . . . . . . . . . . . . . .

South . . . . . . . . . . . . . . . . . . .

Wast . . . . . . . . . . . . . . . . . . .

Negro

Northeast . . . . . . . . . . . . . . . .

Midwest . . . . . . . . . . . . . . . . .

South . . . . . . . . . . . . . . . . . . .

West . . . . . . . . . . . . . . . . . . .

Both sexes

0.03

0.03

0.03

0.02

0.02

0.04

0.04

0.02

0.08

0.03

0.06

0,08

Boys

0.02

0.03

0.03

0,02

0,01

0.03

0.04

0.03

0.06

0.05

0.06

0.08

Sirls

0.04

0.04

0.03

0.02

0.03

0.04

0.04

0.02

0.10

0.08

0.07

0.10

1 Includes data for “other races, ” which are not shown

separately.

* Includes data for “other races, ” which are not shown

m

.
APPENDIX I

THE DENTAL EXAMINATION

‘1’hc periodontal disease status of sample

youths who participated in the health examinations conducted during 1966-70 was assessed

by the Periodcmtal Index. The procedures for

scurins und calculating the index follow:

The Periodontal Index (P1)

Scows are assigned according to these criteria:

(1 i\lt‘,fdtitle. There is neither overt inflamnmticm in the investing tissues nor loss of

function due to destruction of supporting

tissues.

1 Mild gingivitis. There is an overt area of

in llumnmtion in the free gingivae, but the

.Irca does not circumscribe the tooth.

2 Gin,giz~iti.r. Inflammation completely cir-

~wmscribus the tooth, but there is no appitrent break in the epithelial attachment.

(i G’i}2givitis with pocket formation. The

. .

~’Plthellal uttachrnent has been broken and

there is a pocket (not merely a deepened

gingival crevice due to swelling in the

~ingi\2e). There is no interference with

nurmal masticator function; the tooth is

firm in its socket and has not drifted.

s .1dt~(ltl~~’ddestruction with lOSS of mastiLw[ury .thzction. The tooth may be loose;

mity huve drifted; may sound dull on percussion with a metallic instrument.

RULE: When in doubt, assi~ the lesser

score. Each tooth present in the mou’th, urdess it

is ii root, is scored, and the arithmetic average of

all scores is the individual’s PI.

Training of Examiners

Each of the 6,757 sample youths who received dental examinations during 1966-70 was

examined by one of seven dentists. The dentists

included two senior examiners, A and B, who

trained and supervised the other examiners–C,

D, E, F, and G.

Sample youths were not assigned randomly or

equally among the various examiners. At most

survey locations youths were examined by only

one dentist—C, D, E, F, or G. At 14 of 40 locations, however, a small group was examined only

by either A or B. Thus the senior dentists made

the examination for few sample youths. The

number and percent distribution of youths examined by each dentist were as follows:

Number of

Percent

Examiner

distribution of

wmple youths

sample youths

examined

examined

All examiners . . . . . .

I

6,757 100.0

I

A . . . . . . . . . . . . . . . . . . 236 3.5

B . . 302 4.5

c: :::::::::::::::.. 1,055 15.6

D . . . . . . . . . . . . . . . . . . 448 6.6

E . . . . . . . . . . . . . . . . . . 1,689 25.0

F . . . . . . . . . . . . . . . . . . 1,472 21.8

G . . . . . . . . . . . . . . . . . . 1,555 23.0

Most examinations completed by the senior

dentists resuIted from a pIanned series of replicate examinations. As a rule, the findings of the

senior dentists were included in the sample

youth’s examination record, and the findings of

the dentist with whom he was paired were kept

separate. The primary aim of the replicate examinations was to correct any examiner divergence

from the accepted examination procedures.

21
Throughout the replicate examinations, while

the other dentist was absent, the senior dentist

completed his examination first, dictating his

findings to a trained recorder. Then the other

dentist completed his examination, and the senior dentist recorded these findings. Appreciable

interexaminer differences as well as ny procedure that diverged from the accepted one were

discussed and, if indicated, either resolved or

corrected while the sample youth was still

present. However, the findings originality

recorded by the examiner were not altered.

To indicate the level of agreement on the PI,

the results of the replicate examinations are

shown in table I. The direction of the disagreements that occurred is shown by positive or negative numbers. A positive number indicates that

a finding of the senior dentist was lower than

that of the other dentist, while a negative number indicates the opposite.

The data in table I suggest that the level of

examiner agreement between the senior dentists

and other dentists was relatively high. Perfect

agreement resulted in 30.4 percent of the examinations, and about 62 percent of the periodontal

scores differed by no more than 0.1. Differences

greater than 0.3 occurred in only about 13 percent of the examinations.

Table I also gives the percent distribution of

difference between the PI’s assigned by examiners C, D, E, F, and G individually and those

assigned by the senior examiners. Examiners D

and F achieved perfect agreement less often than

did examiners C, E, and G. But no examiner had

an absolute mean or median difference in excess

Ofo.1.

Table 1. Differences in the Periodontal Index between senior dentists and other dentists on replicate dental examinations and percent

distribution of the differences: Health Examination Survey, 1966-70

Difference in Periodontal Index

Median difference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Mean difference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Standard deviation of the difference . . . . . . . . . . . . . . . . . . . .

Number of replicate examinations . . . . . . . . . . . . . . . . . . . . .

Ailreplicata examinations . . . . . . . . . . . . . . . . . . . . . .

-l. O or less . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

-0.9 . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . .

-0.8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

-0.7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

-0.6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

-0.5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

-0.4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

-0.3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

-0.2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

-0.1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

0,0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

0.1..........................................

0.2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

0.3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

0.4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

0.5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

0.6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

0.7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

0.8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

0.9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

l.O or more . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Examiner

C, D, E, F,G c D E F G

0.0 0.0 0.1 0.0 0.0 0.0

-0.01 -0.01 0.10 -0.03 -0.01 -0.01

0.31 0.33 0.17 0.34 0.32 0.19

407 47 25 162 126 47

Percent distribution

100.0

2.2

0.3

0.3

0.3

0.7

1.0

2.7

3.4

8.6

13.0

30.4

18.4

7.6

5.2

2.5

1.1

0.5

0.5

0.5

0.5

0.3

100.0

4.3

2.1

4.3

8.5

14.9

27.7

21.3

4.3

4.3

4.3

2.1

2.1

—100.0

24.0

24.0

20.0

8.0

16.0

4.0

4.0

100.0

2.5

0.6

0.6

1.2

0.6

2.5

3.7

7.4

13.6

33.3

14.8

10.5

03.1

-2.5

0.6

0.6

0.6

0.6

0.6

100.0

2.4

0.8

1.6

4.7

2.4

10,3

11.1

23.0

24.6

6.4

6.4

0.4

2.4

0.8

0.8

0.8

—100.0

2.1

2.1

6.4

12.8

8.5

42.6

10.6

4.3

4.3

6.4

22
●

APPENDIX II

DEMOGRAPHIC AND

. l,q,. - The age recorded for each youth was

the ,ISC at last birthday on the date of examin:~ti~.)n.The age criterion for inclusion in the

s.nnplc used in this survey was defined in terms

~~f ;i~c ;lt time of interview. Since the examin:ltilm usually took place 2-4 weeks after the

inturvicw, some of those who were 17 years old

:It [hc time of interview became 18 years old by

the time of examination. There were 23 such

~..ws. In the adjustment and weighting procedtlYcs used tu produce national estimates, these

S:} IVCWincluded in the 17-year-old group.

l{(l(” (’. R;icc was recorded as “white,”

“Nty+ru,” or “other races. ” “Other races” inL-lul~cd American Indian, Chinese, Japanese, and

AHY;LCCSother than white or Negro. Mexican perSUM were included with “white,” unless definitely known to be American Indian or of an-

(.)1h~’r r:l~’c. Negroes find persons of mixed Negro

Lmd {}ther pm-entage were recorded as “Negro. ”

GfIf~,gn@hic region. – For purposes of stratifi,wti{ ]n the United States was divided into four

~cu~r,lphic regions of approximately equal popul;tti(tn. These regions, which correspond closely

It} those used by the U.S. Bureau of the Census,

\\’L’rc ;1s follol\w:

11’(’,qio}l

N( WthCMi

hlidwest

S~mth

West

States included

Maine, Vermont, New Hampshire,

hlassachusetts, Connecticut, Rhode

Iskmd, New York, NewJersey, and

Pennsylvania

Ohio, Illinois, Indiana, Michigan,

Wisconsin, Minnesota, Iowa, and

Missouri

Dela\vme, Maryland, District of

Columbia, West Virginia, Virginia,

Kentucky, Tennessee, North

Carolina, South Carolina, Georgia,

Florida, Alabama, Mississippi,

Louisiana, and Arkansas

Washington, Oregon, California,

Nevada, New Mexico, filzona,

SOCIOECONOMIC TERMS

Texas, Oklahoma, Kansas,

Nebraska, North Dakota, South

Dakota, Idaho, Utah, Colorado,

Montana, Wyoming, Alaska, and

Hawaii

Family into me.–The income recorded was

the total income received during the past 12

months by the head of the household and all

other household members related to the head by

blood, marriage, or adoption. This income was

the gross cash income (excluding pay in kind)

except when a family had its own farm or business, in which case net income was recorded.

Parent.– A parent was the natural parent or,

in the case of adoption, the legal parent of the

child. Guardian.–A guardian was the person

responsible for the care and supervision of the

youth. He (or she) did not have to be the legal

guardian to be considered the guardian for this

survey. A guardianship could only exist when

neither parent resided within the sample

household.

Head of household. –Only one person in each

household was designated as the “head.” He (or

she) was the person who was regarded as the

“head” by the members of the household. In

most cases the head was the chief breadwinner

of the family although this was not always true.

In some cases the head was the parent of the

chief earner or the only adult member of the

household.

Education of head of household.–The highest

grade completed in school was recorded. The

only grades counted were those completed in a

regular public or private school where persons

receive formal education, either during the day

or night, with either full-time or part-time attendance. A “regular school” is one which advances a person toward an elementary or high

school diploma or toward a college, university,

or professional school degree. Education in vocational, trade, or business schools outside a regular school system was not counted in determining the highest grade of school completed.

23
APPENDIX 111

STATISTICAL NOTES

Survey Design

The sample design for the first three programs

(CycIes I-III) of the Health Examination Survey

has been essentially similar in that each has been

a multistage, stratified probability sample of

clusters of households in land-based segments.

The successive elements of the design are primary sampling unit (PSU), census enumeration

distfict (ED), segment (a cluster of households),

household, eligible youths, and, finaIIy, the sample youth.

The 40 sample areas and the segments utilized

in the design of Cycle III were the same as those

in Cycle II. A previous report describes in detail

the sample design used for Cycle II and also discusses the problems and considerations given to

other types of sampling frames, cluster versus

random sampling, and whether or not to control

the selection of siblings.4

Requirements and limitations placed on the

design for Cycle III, similar to those for Cycle II,

were that:

1. The target population be defined as the

civilian, noninstitutional population of the

United States, including Alaska and Hawaii, aged

12 through 17 years, with the special exclusion

of youths residing on reservation lands of the

American Indians. The I~tter exclusion was due

to operational problems encountered on these

lands in Cycle I.

2. The time period of data collection be

limited to about 3 years for each cycle and the

length of the individual examination within the

specially constructed mobile examination center

be between 2 and 3 hotl.rs.

3. Ancillary data be collected on specially designed household, medical history, and school

questionnaires and from copies of birth

certificates.

4. Examination objectives be primarily related to factors of physical and intellcc[u;d

growth and development.

5. The sample be sufficiently large to yiclrl

reliable findings within broad geographic regions

and population density groups as well as within

age, sex, and limited socioeconomic groups lor

the total sample.

The sample was drawn jointly with the. U.S.

Bureau of the Census, starting with the 1960

Decennial Census list of addresses and the nearly

1,900 PSU’S into which the entire United States

was divided. Each PSU is either u standard metropolitan statistical area (Shl SA ), a county, or a

group of two or three contiguous counties.

These PSU’S were grouped into 4(I strata. each

stratum having an average size of about 4.5 million persons, in such a manner us to maximize

the degree of homogeneity within stratti with

regard to the population size of the PSU’S, degree of urbanization, geographic proximity, and

degree of industrialization. The 40 strata were

then classified into four brcwd geographic

regions of 10 strata each and then within each

region, cross-classified by four population dcmsity classes and classes of rate of popul.ltii.jn

change from 1950 to 1960. Using a modified

Goodman-Kish controlled-selection technique,

one PSU was drawn from each of the 40 strata.

Further stages of sampling within PSU’S required first the seIection of ED’s. The ED’s ;irc

small well-defined areas of about 250 housing

units into which the entire hlation was divided

for the 1960 population census. Etich ED was

assigned a “measure of size” equal to the

rounded whole number resuIting from a “division by 9“ of the number of children, aged

24
5-9, in the ED at the time of the 1960 census. A

sample of 20 ED’s in the sample PSU was selected by systematic sampling, with each ED

h.wing it probability of selection proportional to

the popuhtion of children 5-9 years at the time

L)l’the 1960 census date. A further random seIcctiun by size of segments (smaller clusters of

housing units) within each ED was then made.

Bt-uuse of the 3-year time interval between

Cyclr II and Cycle III, the Cycle III frame had

tt ~bc supplemented for new construction and to

cctnlpcnsate for segments where housing was

partiully or totally demolished to make room for

hi~hwuy construction or urban redevelopment.

Adv:mced planning for the examinations at

the wwious locations or stands provided for

~lhuut 17 days of examinations, which limited

the number of examinces per location to approxinmtely 200. When the number of eligible

youths in the sample drdwn for a particular location exceeded this figure, subsampling was

done by dtdcting from the master list of eligible

youths (ordered by segment, household order

within segment, and age within household) every

nth name on the list starting with the yth name,

v being a number between 1 and n selected randomly and n being the extent of oversampling in

the original draw.

In Cycle III, as in Cycle II, twins who were

dclctcd in the sample selection were also scheduled fur examination, time permitting, as were

)’ouths deleted from the Cycle III sample who

h;ld been examined in Cycle II. ‘

The sample was selected in Cycle III, as it had

bum in Cycle II, so as to contain the correct

proportion of youth from families having only

(mc r!igiblc youth, two eligible youths, and so

an, to be representative of the total target population. However, since households were one of

the elements in the sample frame, the number of

related youths in the resultant sample is greater

th:m would come from a design that sampled

youths 12-17 years without regard to household.

The resultant estimated mean measurements or

mtcs should be unbiased, but their sampIing variability will be somewhat greater than those from

more costly, time-consuming systematic sample

design in which every kth youth would be seMcd.

The total probability sample for Cycle III included 7,514 youths representative of the approximately 22.7 million noninstitutionalized

U.S. youths aged 12-17 years. The sample contained youths from 25 different States and approximately 1,000 in each single year of age.

The response rate in Cycle III was 90 percent,

with 6,768 youths examined out of the total

sample. These examinees were closely representative of those in the samples as well as the population from which the samples were drawn with

respect to age, sex, race, region, population density, and population growth in area of residence.

Hence, it appears unlikely that nonresponse

could bias the findings appreciably.

Reliability

While measurement processes in the surveys

were carefully standardized and closely controlled, the correspondence between the real

world and survey results cannot be expected to

be exact. Survey data are imperfect for three

major reasons: (1) results are subject to sampling

error, (2) the actual conduct of a survey never

agrees perfectly with the design, and (3) the

measurement processes themselves are inexact “

even though standardized and controlled.

The report that describes the plan and operation of Cycle 1112 gives in detail the faithfulness

with which the sampling design was carried out.

Data recorded for each sample youth are inflated in the estimation process to characterize

the larger universe of which the sample youth is

representative. The weights used in this inflation

process are a product of the reciprocal of the

probability of selecting the youth, an adjustment for nonresponse cases, and a poststratified

ratio adjustment that increased precision by

bringing survey results into closer alignment

with known U.S. population fi~res by race and

sex within single years of age from 12 through

.,..

1/.

In the third cycIe of the Health Examination

Survey (as for the children in Cycle II) the samples were the resuIt of three principal stages of

selection—the single PSU from each stratum, the

20 segments from each sample PSU, and the

sample youth from the eligible youths. The

probability of selecting an individual youth is

the product of the probability of selection at

each stage.

25
.

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

youths were examined in each of the sample

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

that is, each youth 12 through 17 years had

about the same probability of being drawn into

the respective samples.

The adjustment upward for nonresponse is intended to minimize the impact of nonresponse

on final estimates by imputing to nonrespondents the characteristics of “similar” respondents. Here “similar” respondents were judged

to be examined youths in a sample PSU having

the same age (in years) and sex as youths not

examined in that sample PSU.

The poststratified ratio adjustment used in

CycIe 111 achieved most of the gains in precision

which would have been attained if the sample

had been drawn from a population stratified by

age, color, and sex. The adjustment made the

final sample estimates of population agree exactly with independent controls prepared by the

U.S. Bureau 01’ the Census for the noninstitutional population of the United States as of

March 9, 1968 (approximate midsurvey point

for Cycle III), by color and sex for each single

year of age 12-17 years. The weight of every

responding sample youth in each of the 24 age,

color, and sex classes is adjusted upward or

downward so that the weighted total within the

class equals the independent population control

for each survey.

Sampling and Measurement Error

In this report and its appendixes several references have been made to efforts to evaluate both

bias and variability of the measurement techniques.

The probability desi,gn of the survey makes

possible- the calculation-of sampling errors. The

sampling error is used here to determine how

imprecise the survey test results may be because

they come from a sample rather than from the

measurements of all elements in the universe.

The estimation of sampling errors for a study

of the type of the Hm.lth Examination Survey is

difficult for at least three reasons: (1) measurement error and “pure” sampling error are confounded in the data–it is not easy to find a

procedure that wilI either complet~ly inclurlr

both or treat one or the other separately, (2) the

survey design and estimation procedure w-e conlplex and accordingly require computaticmally involved techniques for the calculation of v:iriances, and (3) from the survey are coming thousands of statistics, many for subclasses of the

population for which there are a small nunlbc]-

of cases. Estimates of sampling error are {JIItained from the sample data and are themselves

subject to sampling error which may be Iurxc

when the number of cases in a cell is small or

even occasionally \vhen the number of cases is

substantial.

Estimates of approximate sampling vwiubility

for selected statistics used in this report m-c included in tables 6-10. These estimates huvc been

prepared by a replication technique that yields

overall variability through observation of vm-iubility among random subsamples of the tc]tal

sample. The method reflects both “pui-c” s:mlpling variance and a part of the measurcmen[

variance. A similar pseudoreplicaticm technique

was used to estimate the standard errors of the

correlation coefficients shown in the “Discussion” section.g

By the end of the survey of youths, only 11

youths examined had not received a dental examination. These 11 examined youths received

imputed dental findings. The imputed vafucs

were randomly selected from a pool of adolescents’ dental records that had thd same or sinliIar demographic characteristics. The age-srx distribution for the 6,757 youths given the dental

examination and the 11 sample yoLlths for

whom findings were imputed are shown in ttible

II. The estimated U.S. population aged 12-17

years by race, sex, and age is shown in table III.

Tests of Significance

Tests of significance for Periodontal Index

scores by selected demographic characteristics

were performed in one of two ways. The first is

to determine if the difference between two estimated means is equal to or greater than two

times the standard error of the difference. The

test assumes, in accordance with usual practice,

that a 68-percent confidence interval rfinges

within 1 standard error of the tabulated sta~istics and that a 95-percent confidence interval

26
Table 11. Number of examined sample youths, by receipt of dental examination, sax, and age: Health Examination Survey, 1966-70

All

Dantal examination given No dental examination given

Age

youths

Boys Girls Boys Girls

Total, 12-17 years . . . . . . . . 6,768 3,545 3,223 7 4

12years . . . . . . . . . . . . . . . . . . . 1,190 643 547 1 2

13years . . . . . . . . . . . . . . . . . . . 1,208 626 582 1

14 years . . . . . . . . . . . . . . . . . . . 1,204 618 586

15years . . . . . . . . . . . . . . . . . . . 1,116 613 503 1

16years . . . . . . . . . . . . . . . . . . . 1,092 556 536 2 1

17years . . . . . . . . . . . . . . . . . . . 958 489 469 2 1

Table ill. Estimated number of noninstitutionalized youths, byrace, sex,

and age: Unitad States, 1966-70

Age

Total, 12.17 yeara . .

12yws .. . . . . . . . . . . .

13yws. ., ., .,,,....

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

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

16vears, . . . . . . . . . . . .

Ilyears . . . . . . . . . . . . .

All White All other

races

Boys Girls Boys Girls

Number in thousands

m

22,692 9,930 9,622

4,003 1,747 1,685

3,952 1,729 1,667

3,851 1,6e6 1,632

3,750 1,646 1,594

3,625 1,594 1,542

3,511 1,528 1,502 I

1,560 1,5B0

286 286

277 279

265 26B

254 256

242 247

237 244

rim~cs within 2 standard errors. An approximation; of the standard error of the ‘difference

c/=x-y oft~vostatistics xandyisgiven by the

formula

Sd=(s:+sy

where SX and S,, are standard errors, respectively, uf x and-y, shown in tables 6-10. For

txm-npk, table 2 shows that the mean PIis 0.46

for Negroes aged 12 years and 0.68 for Negroes

aged 17 years, while table 7 indicates that the

skndard error of Negroes aged 12is.03 and that

of Ne~~oes aged 17 is .10. The formuIa yields an

estimated standard error of the difference

(d=-.22) of Sd=.1044. Thus, as the observed

difference is more than twice its standard error,

it can be concluded that the mean PI of Negroes

aged 12 is significantly lower than that of

Negroes aged 17 years,

The second test is to determine if the difference between the estimated actual and expected

values is at least two times the standard error of

the actual value. For example, for white youths

in families with a yearly income of less than

$3,000, the difference between the actual and

expected mean periodontal scores is 0.20 (table

3) and the standard error is 0.03 (table 8). Since

the difference is at least twice the standard

error, it is deemed statistically significant.

The criterion for significance among geographical regions was more stringent than that

for other demographic characteristics. To determine whether the difference between estimated

means for youths in any two of the four geographic regions was significant, the difference

was required to be at least 2.5 times the standard error.

Small Numks

In some tables ma~itudes are shown for cells

for which the sample size is so small that the

sampling error may be several times as great as

the statistic itself. Obviously in such instances

the statistic has no meaning in itself except to

indicate that the true quantity is small. Such

numbers, if shown, have been included in the

belief that they may help to convey an impression of the overall story of the table.

Expected Values

In tables 3 and 4 the actual mean PI per person is compared with expected estimates. The

computation of the expected rates were done as

follows.

27
Suppose it is estimated that in a subgroup

there are A’i persons in the ith age group (i= 1,

2>.. . 6; sum of Ni = N). Suppose it is estimated

that the mean PI per person for the United

States in the ith age-sex group is ~j. Then the

expected mean PI for the subgroup is

Comparison of any actual value for, say, an

income group with the expected value for that

region is undertaken on the assumption that a

meaningful statement can be made which hoIds,

in some average way, for all youths who are in

the family income group. This may or may not

be true. The specified income group may have

higher values for younger youths and lower values for older youths than those found in other

income groups, In that case an average comparison would obliterate one or both of these differentials.

In arriving at the general conclusions expressed in the text, an effort was made to consider all the specific data, including data not presented in this report; but it must be recognized

that balancing such evidence is a qualitative exercise rather than a quantitative one. The standard error of the difference between an actual

and expected value may be approximated by the

standard error of the actual value (tables 8 and

9).

Uuo

28
Series 1.

Sm”es 2.

Series 3.

Series 4.

Sm”es 10.

Series 11.

Series 12.

Series 13.

Series 14.

Series 20.

Series 21.

Series 22.

VITAL AND

Formsrly

HEALTH STATISTICS PUBLICATION SERIES

Public HealthSsrvice Publication No. 1000

Prog?ums and collectwn procedures. —Reports which describe the general programs of the National

Center for Health Statistics and its otYLcesand clivisions, data collection methods used, defLnLtLons,

and other material necessary for understanding the data.

ZMa evaluation and methods research. - Studies of new statistical methodology including: experimental tests of new survey methods, studtes of vital statistics collection methods, new analytical

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

Analytical studies .-Rep@ts presenting analytical or interpretive studies bssedon vital and health

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

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

Mrth and death certificates.

llzka Porn the HeaUh Interview Survev. —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 interview survey.

Data Porn the Hgulth Examination Survey. —Data from direct examination, testing, and measurement of national samples of the civilian, noninstitutional population provide the basis for two types

of reports: (1) estimates of the medically defined prevalence of specific diseases in the Unfted

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.

DOta from the Institutional Population Surveys —Statistics relating to the health characteristics of

persons in institutions, and their medical, nursing, and personal care received, based on national

samples of establishments providing these services and samples of the residents or patients.

Data from the Hospital Discharge Survey. —Statistics relating to {Iis,i ,~:-ged patients in short-stay

hospitals, based on a sample of patient records in a national sample (ri hospit~ls.

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.

Data on morality. —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, also

geographic and time series analyses.

Data on natality, marriage, and divovce. —Various statistics on na~ality, marriage, and divorce

other than as included in regular annual or monthly reports+ pecial analyses by demographic

variables, also geographic and time series analyses, studies of fertility.

DatQ from the National Nafnlity and Morkzlity Surveys. —Statistics on characteristics of births

and deaths not available from the vital records, based on sample surveys stemming from these

records, including such topics as mortality by socioeconomic class, hospital experience in the

last year of life, medical care during pregnancy, health insurance coverage, etc.

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

*

National Center for Health Statistics

Public Health Service, HRA

Rockville, Md. 20852

/