Characteristics of Personswith Corrective Lensespopulation aged 3 and over had corrective lenses,...

Data from theNATIONAL HEALTH SURVEY

Characteristics of

PersonswithCorrective Lenses

Ihited States -1971

Statistics on persons aged 3 years and over by

selected demographic characteristics. Based ondata collected in household interviews during

1971.

DHEW Publication No. (HRA) 75-1520

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

Public Health Service .

Series 10Number 93

Health Resources Adm inistrat ion

National Center for Health Statistics

Rockville, Md. September 1974

Library of Congress Cataloging in Publication Data

Wilder, Mary H.Characteristics of persons with corrective lenses, United States–1971.

(Vital and health statistics. Series 10: Data from the National Health Survey, no. 93)(DHEW publication no. (HRA) 75-1520)

“Statistics on persons aged 3 years and over by selected demographic characteristics,based on data collected in household interviews during the period 197 1.“

Supt. of Dots. no.: HE 20.6209: 10/931. Ophthalmic Ienses–United States–Statistics. 2. United States–Statistics, Medical.

I. Title. II. Series: United States. National Center for Health Statistics. Vital and healthstatistics. Series 10: Data from National Health Survey. Data from the Health InterviewSurvey no. 93. III. Series: United States. Dept. of Health, Education, and Welfare. DHEWpublication no. (HRA) 75-1520. [DNLM: 1. Contact lenses–Statistics. 2. Eyeglasses–Statistics. W2A N148vj no. 93 1974]RA407.3.A346 no. 93 [RE962] 312’.0973sISBN 0-8406 -0020-8 [312’.3’04752] 74-8410

For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402-Price $1.05

NATIONAL CENTER FOR HEALTH STATISTICS

EDWARD B. PERRIN, Ph. D., Director

PHILIP S. LAWRENCE, SC.D., Deputy DirectorJACOB J. FELDMAN, Ph.D., Acting Associate Director for Analysis

GAIL F. FISHER, Associate Directorfor the Cooperative Health Statistics SystemELIJAH L. WHITE, Associate Director for Data Systems

IWAO M. MORIYAMA, Ph. D., Associate Directorfor International StatisticsEDWARD E. MINTY, Associate Director for MwuzgemetztROBERT A. ISRAEL, Associate Director for operations

QUENTIN R. REMEIN, Associate Director for Program DevelopmentPHILIP S. LAWRENCE, SC.D., Actin~ Associate Director for Research

ALICE HAYWOOD, Information Officer -

OF HEALTH INTERVIEW STATISTICS

ROBERT R. FUCHSBERG, Director

RONALD W. WILSON, Chief, Arudysis and Reports Branch

KENNETH W. HAASE, Chief, Survey Methods Branch

COOPERATION OF THE BUREAU OF THE CENSUS

Under the legislation establishing the National Health Survey, the Public

Health Service is authorized to use, insofar as possible, the services or facili-

ties of other Federal, State, or private agencies.

In accordance with specifications established by the Health Interview Sur-

vey, the Bureau of the Census, under a contractual arrangement, participates

in most aspects of survey planning, selects the sample, and collects the data.

Vital and Health Statistics-Series 10-No. 93

DHEW Publication No. (HRA) 75-1520

Library of Congress Catalog Card Number 7’4-8410

Introduction . . . . . . . . .

Summary . . . . . . . . . .

Source and Limitations of the Data

Demographic Characteristics . . .Sexand Age . . . . . . .Geographic Region . . . . .Place of Residence . . . . .Color . . . . . . . . . .Family Income . . . . . .

Education of Head of Family .Education of Individual . . .Occupational Status . . . .

Comparison with Earlier Data . . .

List of Detailed Tables . . . . .

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Appendix I. Technical Notes on MethodsBackground of This Report . . . .

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Statistical Design of the Health Interview SurveyGeneral Qualifications . . . . . . . . . .-.Reliability of Estimates . . . . . . . . . .Guide to Use of Relative Standard Error Charts .

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Appendix II. Definitions of Certain Terms Used in This Report .

Appendix HI. Form for Recording Information on Corrective Lenses

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Page

1

1

1

2

23344

5

5!5

6

9

2626

26282931

34

37

SYMBOLS

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

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

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

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

Figure does not meet standards ofreliability or precision (more than30 percent relative standard error) ---------- *

iv

CHARACTERISTICS OFPERSONS WITH CORRECTIVE LENSES

Mary H. WiIder, Division of Health Interview Statistics

INTRODUCTION

This report from the Health Interview Sur-vey presents data on the use of corrective lensesfor persons 3 years of age and over. Estimates arederived from a survey during 1971 of the civilian,noninstitutionalized population of the UnitedStates. Corrective lenses include eyeglasses andcontact lenses. The term “corrective Ienses” islimited to visual aids worn to correct or improvevision and therefore excludes sunglasses wornonly to filter light, safety glasses worn only forprotection of the eyes, hand magnifying glasses,and other such devices. However, if the safetyglasses are worn also for correction or improve-ment of vision, they are considered correctivelenses, as are prescription glasses. This reportanalyzes use of corrective Ienses by various demo-graphic characteristics.

An earlier report from the Health InterviewSurvey presented data on corrective lenses basedon the July 1965-June 1966 survey. It containedinformation on age at which persons first ob-tained corrective lenses, type of prescription,usage, and the source of the optical examinationif the individual was examined during the 2-yearperiod prior to interview (“Characteristics ofPersons with Corrective Lenses: United States,July 1965-June 1966,” Vital and Health Statis-tics, Series 10, Number 53).

A later section of the present report com-pares demographic differences in the proportionof the population with corrective lenses for thetwo time periods.

SUMMARY

Approximately 94 milIion persons aged 3years and over in the civiIian, noninstitutional-ized population had some type of corrective lensin 1971. This represented 49.2 percent of thepopulation in this age group. About 2.1 percenthad contact lenses.

The folIowing statements summarize thedata ~resented in this reKIort:

‘1.

2.

3.

4.

5.

6.

The proportion of the populationwith corrective lenses increased withage.The Iargest proportion of contact lenswearers were 17-24 years of age.Females were more likely to have cor-rective lenses than were maIes.Approximately half of the white pop-ulation had corrective Ienses com-pared to a third of all other persons.Within each age group, as family in-come increased, the proportion ofpersons with corrective lenses alsoincreased.White-colIar workers were more likely

to have corrective lenses than wer~other persons in the Iabor force.

SOURCE AND LIMITATIONSOF THE DATA

The information from the Health InterviewSurvey presented in this report is based on data

collected in a continuing nationwide survey con-ducted by household interview. Each week aprobability sample of households is interviewedby trained personnel of the U.S. Bureau of theCensus to obtain information about the healthand other characteristics of each member of thehousehold in the civilian, noninstitutionaIizedpopulation of the United States. During the 52weeks in 1971 the sample was composed of ap-proximately 42,000 households containingabout 134,000 persons living at the time of theinterview.

A description of the design of the survey,the methods used in estimation, and generalqualifications of the data obtained from surveysare presented in appendix 1. Since the estimatesshown in this report are based on a sample ofthe population, they are subject to sampling er-ror. Therefore particular attention should bepaid to the section entitled “Reliability of Esti-mates. ” Sampling errors for most of the esti-mates are of relatively low magnitude. However,where an estimated number or the numerator ordenominator of a rate o,r percentage is smalI, thesampling error may be high. Charts of relativesampling errors and instructions for their use areshown in appendix I.

Certain terms used in this report are de-fined in appendix II. Some of the terms havespecialized meanings for the purpose of the sur-vey.

The questionnaire used in the Health Inter-view Survey during 1971 is illustrated in thepublication “Current Estimates from the HealthInterview Survey, United States, 1971” ( Vitaland Health Statistics, Series 10, N-umber 79).The portion of the questionnaire used to obtaindata for persons with corrective lenses is illus-trated in appendix III. Although questions aboutcorrective lenses were asked for persons of allages, the data are restricted to persons 3 years ofage and over, since very few children under age 3have glasses.

The restriction of the survey to the civilian,noninstitutionalized population living at thetime of the survey obviously produces an under-estimation of persons with corrective lenses inthe total population. The estimates of personswith corrective lensesmay not represent the

2

in the age group 17-24true picture for males in

this age group because of the exclusion of mem-bers of the Armed Forces. Likewise, the ex-clusion of the institutionalized population maydistort estimates of the number of older personswearing corrective lenses.

DEMOGRAPHIC CHARACTERISTICS

During 1971 an estimated one-half (49.2percent) of the civilian, noninstitutionalizedpopulation aged 3 and over had correctivelenses, based on data collected by the U.S. Bu-reau of the Census for the Health Interview Sur-vey (tables 1 and 2). This represents approxi-mately 94 million persons, including 3,972,000persons with contact lenses. The following dis-cussion characterizes the population with cor-rective lenses by age, sex, geographic region,place of residence, color, family income, educa-tional level of the head of each family unit, edu-cational level of each individual 17 years andover, and occupational status of each individual17 years and over in the labor force. Each ofthese characteristics is related to the use of cor-rective lenses. Other factors which produce aneed for’ corrective lens usage, such as heredity,congenital abnormalities, illness, and injury, arenot considered in this study. ‘J ~ ‘

Sex and Age

Data shown in figure 1 and tabIe 2 indicatethat the age pattern of persons who used cor-rective lenses is quite similar for males and fe-males, although the level is higher at all age in-tervals among females. The age curve for each ofthe sexes displays two well-defined plateaus, thefirst encompassing the age intervals 17-24 and25-44 years and the second spanning the inter-vals 55-64 and fj5 years and over. This curvedemonstrates the typical pattern of the need forvisual correction. During early childhood andthe teens, the need for visual correction usuallybecomes apparent when a person has difficultyin reading, complains of eyestrain, or has otherproblems related to school activities or employ-ment. Usually by age 20 persons with myopia,strabismus, congenital eye defects, and otherconditions causing visual impairment have beenidentified and corrective lenses have been ob-tained. As a rule, changes in visual acuity are at a

100 -

90 —

80 —

70 —

60 —*$c1 50 —E2

40 —

30 —

20 –

10 -

...-------------”— Male . ...”

----- Female ...””~.

...

...~.

......

./”...

j...

.. . . . . . . . . . . . . . . -“....

...

...”/

.../

..:;.

AGE IN YEARS

Figure 1. Percent of persons with corrective lenses, by ageand sex.

minimum during the age intervaI 25-44 years;dwn, during the midforties, the graduaI deterio-ration of near vision due to the aging process(prcsbyopia) Icads to an increased proportion ofpersons in need of corrective lenses. The generalprevalence of this condition causes a sharp rise

❑ EW,hmds ❑ ‘:h;!;g:::::4GE

95.8 42

,,,, , H,,,

9G.4 36.<, ..,,.. . .

83.7 lG.3

1724 yearsJ

92.9 7,1

?~ .~ yea=

99,2 0.845 yews and

cwr.%.yyy~~.~ ,>; .:>;:; ?,,.+ ;.,/:.;,,:.:{.2.;.;.:...:-.;. . . . . . . . . .. . . . . . . . .. . . .

) ! I I 1 f I 1 ! t 1

0 10 20 30 40 50 60 70 80 90 100

PERCENT

Figure 2. Percent distribution of persons with corrective lensesby type of lens, according to age.

during the forties and fifties, with another Ievel-ing off in the percentage of persons with cor-rective lenses beyond age 60.

Among persons with contact lenses, ap-proximately 45.5 percent were 17-24 years ofage, and 35.8 percent were 25-44 years of age.About 16.3 percent of all persons aged 17-24with corrective lenses had contact lenses (figure2). Approximately three-fourths of alI contactlens owners were females. This predominance offemales over maIes, particularly in the youngerages, is probably due to the cosmetic aspects ofwearing contact Ienses in preference to eye-glasses.

Geographic Region

A smaller proportion of the populationliving in the South Region (44.9 percent) re-ported having corrective lenses during 1971 thandid persons living in the remaining regions(tables 3 and 4). About 48.2 percent of the pop-ulation in the West Region, 51.6 percent in theNorth Central Region, and 52.7 percent in theNortheast Region reported the use of correctiveIenses.

The lower proportion of the population inthe South Region having corrective Ienses prob-ably reflects the larger proportion of personsother than w’bite who reside in this region. Thisgroup has a comparatively lower rate of physi-cian services ( J ‘ital and Health Statistics, Series10, Number 75). The regiomd pattern of cor-recti~~c lens use is consistent with the rate ofpersons who visited an ophthalmologist or op-tometrist during an average year ( I ‘ital andHealth Statistics, Series 10, Number 28).

The regions having the Iargest proportionof persons wearing contact lenses were the WrestRegion, where 2.8 percent of the population had“contacts” \vhich were used with or withouteyeglasses, and the North Central Region, where2.5 percent of the population had this type oflens.

Place of Residence

‘ A slightly smaller percentage of personsli~’ing outside metropolitan areas had correctivelenses than did persons living in metropolitanareas (tables 5 and 6). Among residents of stand-ard metropolitan statistical areas (SMSA’S), pro-

3

portionately more persons residing within thecentral city of the area had corrective lensesthan did persons living outside the central city.The age composition of central city residents is aslightly older one than that of residents outsidethe central city. When the data are age-adjustedlto the age distribution of the population 3 yearsand over, the relationship of residence and usageof corrective lenses is reversed.

Unadjusted Age-adjusted

Percent

Central city ........... .... ... 50.2 48.8Outside central city ...... 49.4 50.5

SimiIarly for the populations living outsideSMSA’S, the farm population is older than thenonfarm population. Whereas nonfarm personswere less likely to have corrective lenses than thefarm population, age adjusting the data to cor-rect the age distribution shows the followingresults.


Percent

Nonfarm .......... .. .. ....... 47.9 48.3Farm ...... ....... ... .... ....... 50.9 47.0

About three-fourths of the persons withcontact lenses resided in metropolitan areas.There was little difference in the proportion ofthe population with this type of lens among thetwo residential groups in metropolitan areas.About 93.4 percent of the population living out-side SMSA’S who had contact Ienses were non-farm residents.

Color

About one-half of the white population re-ported having some type of corrective lens com-pared with about one-third of all other persons

1Age adjustment is computed by multiplying thespecific rate for each age group by the population fromthe corresponding age group in the total civilian, nonin-stitutionalized population 3 years and over in 1971. Therate is obtained by dividing the cumulative figures previ-ously computed by the total populaticm 3 years andover.

(tables 7 and 8).2 Since the white population isthe older of the two color groups, age adjust-ment of the data for persons with correctivelenses decreased the difference between the twogroups, although comparatively more white per-sons still had glasses than did others.


Percent

White ............. ....... ... ... 51.4 50.6All other ...................... 33.6 38.4

About 96.2 percent of persons with con-tact lenses were white.

Family Income

The proportion of persons with correctivelenses was greater for members of family groupswith annual income of less than $5,000 than itwas for any other income group shown in tables9 and 10. This finding largely reflects the agecomposition of the income groups, since withineach age group the proportion of persons withcorrective lenses increased as family income in-creased. The lowest income group contains thelargest proportion of older persons, andl thesepercentages are shown below.

Percent of population45 years and over

Less than $5,000 ........ ............ .. 46.9$5,000-$9,999 .............. ............ 28.5$10,000-$14,999 ..... .... .............. 23.6$15,000 or more .... ..... ..... ....... .. 29.4

Age adjustment of the data produces a pat-tern that exhibits this relationship between in-creasing income and the probability of using cor-rective lenses which was not reflected in the un-adjusted data.


Percent

Less than $5,000 ........... 54.7 45.2$5,000-$9,999 ............... 46.1 48.0$10,000-$ 14,999 ............ 46.2 51.1$15,000 or more ........ .... 51.5 52.9

2Data from the Health Examination Survey showthat there is little difference in visual acuity betweenwhite population groups and other persons (Vital andHealth Statistics, Series 11, Numbers 3 and 112).

4

There was a direct relationship between in-come and use of contact Ienses. The proportionof persons using “contacts” ranged from 1.4 per-cent among the income group under $5,000 to3.3 percent in the group $15,000 and over. Infact, 10.1 percent of persons aged 17-24 living infamilies with incomes over $15,000 wore con-tact lenses.

Education of Head of Family

Among persons classified by the educa-tional level of the family head, proportionallymore persons in family groups in which the fam-ily head had Iess than 9 years of formal educa-tion had corrective lenses than did persons inother groups (tables 11 and 12). However, in apattern similar to that of income level, the pro-portion of persons in each age group who hadcorrective lenses increased as education of thefamily head increased. Groups in which the fam-ily head has Iess education tend to contain alarger proportion of elderly peopIe. Age adjust-ing the data to correct the age distributionshows a direct relationship between educationallevel of the family head and the use of correctivelenses.


Percent

Less than 9 years .......... .. 53.9 43.89-11 years ............... ...... .. 45.8 46.512 years .... .................... .. 45.9 49.613 years or more ...... ...... . 51.5 54.5

Approximately 4.1 percent of persons infamilies whose head had the highest IeveI of edu-cational attainment had contact lenses comparedto 0.5 percent of those in families with the low-est level of educational achievement. In fact,50.8 percent of the contact lens users were inthis highest education group.

Education of Individual

Education of the family head is used by theHealth Interview Survey primariIy as an indica-tion of family awareness and economic ability toafford health care. In the corrective lens data, itdoes not describe the population in terms ofneed for corrective lenses because of increasedeyestrain in the pursuit of academic training.

Tables 13 and 14 show data on corrective lensesby education of the individual. The data are re-stricted to persons 17 years and over.

The pattern of corrective lens usage by edu-cation of the individual is similar to that by edu-cation of the family head. For example, only15.0 percent of the persons aged 17-24 with lessthan 9 years of education had corrective lensescompared with 53.8 percent of persons the sameage with some college education. Adjustment ofpercentages to the age distribution of all persons17 years and over produces a direct relationshipbetween educational attainment and having cor-rective Ienses.


Percent

Less than 9 years ....... .... 71.0 51.29-11 years ..... ........ .. ... ... . 55.7 58.312 years ........ ...... .. ........ . 59.2 63.513 years or more ..... ..... . 66.3 70.6

There is a direct relationship between edu-cational attainment and owming contact lenses.In fact, 85.6 percent of the contact Iens wearershad completed high schooI.

Occupational Status

Among persons 17 years and over in thelabor force, 58.9 percent had corrective lenses.A greater proportion of the populationemployed in white-collar jobs had some t>’pe ofcorrective lens (67. 1 percent) than did personsemployed in blue-colku- jobs (49.0 percent). (Seetables 15 and 16.) However, 59.3 percent ofservice workers and 54.4 percent of farmworkers had corrective lenses.

In the white-collar category there was littlevariation between the percent of persons 17-24and 25-44 years having corrective lenses (tableA). Among those under 45 years of age, 55.6percent of the professional group and 53.4 per-cent of the clerical group used corrective lensescompared with 46.4 percent of the managers and47.1 percent of those in sales positions.

Approximately 68.4 percent of the contactlens wearers 17 years and over were in the white-coIIar category. As has been previously stated,the largest proportion of persons reporting theuse of contact lenses with or without glasses is

Table A. Number of white-collar workers 17 years of age and over and percent distribution with or without corrective lenses by type of

Type of white-collar workerand age

Professional workers

All ages 17 years and over . ... .

17-24 years . ..... . .. ...... . . .... .. .. ... ... .25-44 years ... .... . .. .... .. . . .... . ... ... .. .45 years and over ... .. .. ... ... .... ... . ..

Managers

All ages 17 years and over .....

17-24 years . .. ... .... . .. .... . ... ..... . . ....25-44 years .. . ... .... . .. .... .. .. .... .. . ....45 years and over .. . .. ... ... .. .... . ... ..

Sales workers

All ages 17 years and over .. ...

17-24 years ..... . .. ... .. .. ... ... .. .... . . .. .25-44 years . ..... . . .... ... . ..... .. .. ... . .. .45 years and over .... . .. .... .. ... ... . ...

Clerical workers

All ages 17 years and over .. . ..

17-24 years ... ... ... .. .. .. .. .. .. .. .. .... .. .2544 years .. .. .. .. .. .. .... .. .... .. .. ... . ..45 years and over .. ... .. .. .... .. ... .. ...

lens, according to occupation and age: United States, 1971

Number ofpersons 17

years and overin thousands’

11,519

1,7086,0353,776

9,097

5563,8814,660

1,880

289772819

13,771

4,1515,1784,441

Corrective lensesPersons No

17 years corrective Contact lensesand over’ lenses

Tota IEyeglasses with or

only withouteyeglasses

Percent distribution

100.0 32.0 67.7 62.6 5.1

100.0 45.4 54.4 41.5 12.9100.0 43.9 55.9 50.3 5.6100.0 6.8 92.7 91.9 *

100.0 30.5 69.1 67.1 2.0

100.0 55.6 43.9 35.6 8.3100.0 52.7 46.7 43.9 2.9100.0 8.9 90.8 90.2 *

100.0 33.7 65.7 63.4 2.4

100.0 55.4 44.6 37.0 *

100.0 51.7 47.9 45.5 *

100.0 9.0 90.0 89.5 *

100.0 34.1 65.5 59.8 5.8

100.0 47.3 52.4 41.7 10.8

100.0 45.4 54.2 48.4 5.8100.0 8.6 91.0 90.0 1.0

‘ Includes persons for whom no information on corrective lenses was available.

centered in the 17-24 age group. The proportionusing “contacts” among white-collar workers inthis age group (1 1.0 percent) was approximatelytwice that for service workers (5.5 percent) andabout four times that of blue-collar workers (2.6percent). Within the white-collar category morethan 10 percent of the professional workers (1 2.9percent) and clerical workers (1 0.8 percent) inthe 17-24 age group were users of contact lenses(table A).

COMPARISON WITHEARLIER DATA

Data on persons with corrective lenses werecollected in the Health Interview Survey duringthe period July 1965-June 1966. Approximatelythe same percentage of the civilian, noninstitu-tionalized population 3 years and over had cor-rective lenses in 1971 as did persons in the priorsurvey (table B). Children 3-16 years of age were

6

Table B. Percent of Dersons 3 vears of aqe and over with corrective lenses, by type of lens and selected characteristics: United States,

Characteristic

All persons 3 years and overq..

Age

3-16 years ... ... ... . . ... .. . . ... .. .. ... . .... . .

17-24 years .. ..... . .. ... .. . .... . ... .. .. .... ..25-44 years .. . .... ... ... .. .. .. .. .. ... . .. ... . .45 years and over .. .. .. .. .. ... .. .. . ... .. .

Sex—

Male .. .... . .. .... . .. . .... . . ... .. .. .... . . .. .. .. ..Female .. .. . .... ... . ... . .. ... .. ... .. . .. ... .. . ..

Geographic region

Northeast . .... .. . ... .. . . .... . . .... . .. ... .. . ..North Central . . .... . . .. .. .. . ... . ... ... .. . ..South . .. .. .... .. .. .. .. .. .. .... . . .... .. .. .. .. ....West .. .... .. ... . .. . . .... .. .... .. .. ... . .. .. .. ... ..

Place of residence

SMSA .. ... . ... . .. .. .. .. .. ... . ... .. . .. . ... .. .. . .Outside SMSA ... ... . .... . . .... . .. ... ... .. .

d

White .. . ..... . .. .. .. . .... .. . .... .. . ... .. . ... .. .All other ... . .. ... .. .. ... .. .. ... .. . .. ... .... .. .

Family income

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

$5,000 or more .. .. . ... .. . ... .. ... ... ... ..

Education of head of family

12 years or lass .. .... . .. ... ... . .... . . ... .. .13 yeare or more . ... .. ... . ... . ... .. . .... . .

July 1965-June 1966 and 19~1’

July 1965-June 1966 I 1971

Total Contact lenses Total Contact lenses

with Eyeglasses with or with Eyeglasses with orcorrective only without corrective only

lenseswithout

eyeglasses lenses eyeglasses

Percent

-148.1 47.1

15.041.641.988.0

42.853.0

52.550.642.847.0

48.747.0

50.430.7

49.746.7

47.251.1

14.737.840.587.7

42.251.7

51.649.741.845.6

47.546.3

49.330.5

49.045.5

46.648.6

1.0

0.33.71.30.3

0.61.3

0.90.91.01.4

1.20.7

1.1*

0.71.2

0.62.5

49.2

16.6

40.742.188.3

44.253.8

52.751.644.948.2

49.748.3

51.433.6

54.747.5

48.551.5

47.1

16.034.139.187.6

43.150.9

51.149.143.345.4

47.446.7

49.132.9

53.345.2

47.147.4

2.1

0.6

6.63.00.7

1.22.9

1.62.51.72.8

2.31.6

2.30.6

1.42.3

1.44.1

1 Includes persons with unknown income and education.

7

Table C. Percent of persons 17 years of age and over in the labor force with corrective lenses, by type of lens and occupation class:United States, July 1965-June 1966 and 1971

July 1965-June 1966 1971

Occupation class Tota I Contact lenses Total Contact lenseswith Eyeglasses w’ith or with Eyeglasses with or

corrective only without corrective on Iy withoutlenses eyeglasses lenses eyeglasses

Percent

All occupation classes .. . ... ... 5%.9 57.5 1.4 58.9 56.0 2.8

White-collar workers . .. .. .. . ... .. .. 68.1 65.7 2.4 67.1 62.7 4.4Blue-collar workers .. ... .... . ... .. ... 48.8 48.4 0.4 49.0 47.9 1.1Service workers ..... .. .. ... ... .... .. .. 59.2 58.3 1.0 59.3 57.0 2.2Farm workers .. . ..... .. .. ... .. . .... . .. . 51.4 51.2 * 54.4 53.4 *

more likely to have both eyeglasses and contactlenses in 1971 than previously. Persons 17-24years were less likely to wear eyeglasses andmore likely to wear contact lenses. More maleswere wearing glasses in 1971 than in July1965-June 1966. Other population groups show-ing an increase in use of corrective lenses wereresidents of the South Region, persons otherthan white, and persons in low income families(less than $5,000 annually). For each demo-graphic characteristic shown in table B, the pro-

portion of the population 3 years and overwearing contact lenses doubled from July1965-June 1966 to 1971.

Among persons 17 years and over in thelabor force, the proportion with correctivelenses did not change but the proportion of per-sons with contact lenses doubled (table C). Ofthe occupation groups shown in table B, farmworkers were the only group showing a substan-tial increase in the proportion with correctivelenses.

—000

8

LIST OF DETAILED TABLES

Table 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11,

12.

13.

14.

15.

16.

Number of persons 3 years of age and over with or without corrective lenses, bytype of lens, sex, and age: United States, 1971---------------------------------

Percent distribution of p=rsons 3 years of age and o’~er with or without correc-tive lenses by type of lens, according to sex and age: United States, 1971------

Number of persons 3 years of age and over with or without corrective lenses, bytype of lens, geographic region, and age: United States, 1971-------------------

Percent distribution ofpersons 3 years of age and over with orwithout corrective~~s by type of leas, according to geographic region and age: United States,

--.-------------------------------”----”------------------------------------

Number of persons 3 years of age and over with or without corrective lenses, bytype of lens, place of residence, and age: United States, 1971------------------

Percent distribution of persons 3 years of age a?d over with or without correc-tive lenses by type of lens, according to place of residence and age: UnitedStates, 1971--------------------------------------------------------------------

Number of persons 3 years of age and over with or without corrective lenses, bytype of leas, color, and age: United States, 1971-------------------------------

Percent distribution of persons 3 years of age and over with or without correc-tive lenses by type of lens, according to color and age: United States, 1971----

Number of persons 3 years of agetype of lens, family income, and

Percent distribution ofpersons3lenses by type of lens,according

and over with or without corrective lenses, byage: United States, 1971-----------------------

years of age and over withor without correctiveto family income and age:United States,1971----

Number 05 p=rsons 3 years of age and over with or without corrective lenses, bytype of lens, education of head of family, and age: United States, 1971---------

Percent distribution of persons 3 years of age and over with or without correc-tive lenses by type of lens, according to education of head of family and age:United States, 1971------------------------------------------------------------

Number of persons 17 years of age and over with or without corrective lenses, bytype of lens, education of individual, and age: United States, 1971-------------

Percent distributio~ of persons 17 years of age and over with or without correc-tive lenses by type of lens,according to education of individual and age: UnitedStates, 1971--------------------------------------------------------------------

Number of p~rsons 17 years of age and over in the labor force with or withoutcorrective lenses, by type of lens, occupation class, and age: United States,1971----------------------------------------------------------------------------

Percent distribution of persons 17 years of age and over in the labor force withor without corrective lenses by type of lens, according to occupation class andage: United States, 1971--------------------------------------------------------

Page

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

9

Table 1. Number of persons 3 years of age and over with or without corrective lenses,by type of lens, sex, and age: United States, 1971

[Data are based on household interviews of the civilian, rmninstitutiorxdized population. The survey design, general qualifications, andinformation on the reliability of the estimates are given in appendix I. Definitions of terms are given in appendix 11]

Sex and age

Both sexes

All ages 3 years and over-

3-16 years ----------------------17-24 years ---------------------25-44 years---------------------45 years and over---------------

45-54 years -------------------55-64 years -------------------65 years and over -------------

Male


3-16 years ----------------------17-24 years ---------------------25-44 years ---------------------45 years and over ---------------


Female


3-16 years ----------------------17-24 years ---------------------25-44 years ---------------------45 years and over ---------------


I I— .

t’

II I Corrective lenses -----

Persons II No ~--3 years correc -and tive

Contactlenses

overl lenses TotalEyeglasses

onlywith orwithouteyeglasses

191,602

55,78627,27547,42861,11323,24618,51819,349

92,121

28,39312,86322,84228,02311,1378,6958,191

99,481

27,39314,41124,58633,09012,1099,822

11,158

Number of persons in thousands

96,403

46,17716,04527,2286,9524,1461,3281,478

50,926

24,0898,460

14,2854,0922,462

826804

45,476

22,0887,585

12,9432>8601,684

502674

94,284

9,24911,11419,97853,94419,02617,09817,820

40,757

4,1234,3528,457

23,8258,6347,8257,367

53,527

5,1266,763

11,52130,11810,3929,273

10,453

90,313

8,9209,306

18,55553,53218,86616,97617,690

39.669

4,0443.9088;057

23,6608,5837,7657,311

50,644

4,8765,398

10,49729,87210;2839,211

10,378

3291,808.1,423412159122131

:1,088——

4;:400166515956

2,884

2491.3651;023

2461096275

1Includes persons for whom no information on corrective lenses was available.

NOTE : Relative standard errors of estimates for this table are found on chart onpage 32, code A4AN. A guide to the use of the relative standard error charts is onpage 31.

10

Table 2. Percent distribution of persons 3 years of age and over with or without cor-rective lenses by type of lens, according to sex and age: United States, 1971

[Dataare based onhousehold interviewsofthe civihn, noninstitutionalized population.Thesurvey design,generalqualifications, andinformation on the reliability of the estimates are given in appendix L Definitions of terms are given in appendix II]

Sex and age

Both sexes


3-16 years----------------------17-24 years---------------------25-44 years---------------------45 years and over ---------------

45-64 years-------------------55-64 years-------------------65 years and over-------------

Male


3-16 years ----------------------17-24 years---------------------25-44 years---------------------45 years and over---------------

45-54 years-------------------55-64 years-------------------65 years and over-------------

Female


3-16 years----------------------17-24 years---------------------25-44 years---------------------45 years and over---------------

45-54 years-------------------55-64 years-------------------65 years and Over.............

Persons3 yearsandoverl

100.0

100.0100.0100.0100.0100.0100.0100.0

100.0

100.0100.0100.0100.0100.0100.0100.0

100.0

100.0100.0100.0100.0100.0100.0100.0

Nocorrec-tive

lenses

Corrective lenses

Contact

Eyeglasseslenses

Total only with orwithouteyeglasses


50.3

82.858.857.411.417.87.27.6

55.3

84.865.862.5;;.:

9:59.8

45.7

80.652.652.6

1$;

2:;

49.2

16.640.742.188.381.892.392.1

44.2

14.533.837.085.077.590.089.9

53.8

18.746.946.991.085.894.493.7

47.1

16.034.139.187.681.291.791.4

43.1

14.230.435.384.477.189.389.3

50.9

17.837.542.790.384.993.893.0

2.1

0.66.63.00.70.70.70.7

1.2

0.33.4

:::0.50.70.7

2.9

0.9

H0.70.9

lIncludes persons for whom no information on corrective lenses was available.

NOTE : Relative standard errors of estimates for this table are found on chart onpage 33, code P4AN-M. A guide to the use of the relative standard error charts is onpage 31.

11

Table 3. Number of persons 3 years of age and over with or without corrective lenses,by type of lens, geographic region, and age: United States, 1971

[Data are based on household interviews of the civilian, noninstitutionafized population.The survey design, generaI qualifications, andinformation on tllereliability oftliecstimates aregi\,en inappendix I. De~mitions ofterms are#ven inappendix II]

Geographic region and age

All geographic regions


3-16 years---------------------17-24 years--------------------25-44 years--------------------45 years and over--------------

Northeast



North Central



South

All ages 3 ‘years and over-


u



Persons3 years

andover 1

Nocorrec-tive

lenses

Corrective lenses

191,602

55,78627,27547,42861,113

46,052

12,8176,286

11,32915,620

53,035

15,7967,467

13,01816,754

59,496

17,4518,66514,64918,731

33,019

9,7224,8578,43210,007

Contact

Eyeglasses lensesTotal only

with orwithout

eyeglasses


96,403

46.17716;04527,2286,952

21.539

10,2633,4286,2571,590

25,450

12.6454;0277,1331,645

32,451

14,9925,6959,1732,591

16,963

8,2762,8954,6651,126

94,284

9.24911;11419,97853,944

24.286

2,4512,8365,019

13,981

27,376

3,0723,4145,831

15,059

26,723

2,3472,9245,395

16,058

15,899

1,3791,9413,7338,846

90,313

8,9209,306

18,55553,532

23.537

2,4012,4954,74913,891

26,064

2,9522,7665,392

14,955

25.734

2>2542,4875,054

15,938

14,978

1,3131,5583,3598,747

3,972

3291,8081,423

412

749

5034127090

1,312

121648439104

989

4:?340120

921

3:!37498


NOTE : Relative standard errors of estimates for this table are found on chart onpage32, code A4AN. A guide to the use of the relative standard error charts is onpage 31.

12

Table 4. Percent distribution of persons 3 years of age and over with or without cor-rective lenses by type of Iens,according to geographic region and age: United States,1971

[Dataarebasedon householdinterviewsofthecivilian,noninstitutionalizedpopulation.The surveydesign,generalqualifications,andinformationon thereliabilityoftheestimatesaregiveninappendixI.DefinitionsoftermsaregiveninappendixII]

Geographic region and age

All geographic” regions


3-16 years----------------------17-24 years---------------------25-44 years---------------------45 years and over ---------------

Northeast



North Central


3-16 years----------------------17-24 years---------------------~5-44 years ---------------------

45 years and over---------------

South



West


3-16 years----------------------17-24 years-=-------------------25-44 years---------------------45 years and over---------------

Persons3 years

andoverl

100.0

100.0100.0100.0100.0

100.0

100.0100.0100.0100.0

100.0

100.0100.0100.0100.0

100.0

100.0100.0100.0100.0

100.0

100.0100.0100.0100.0

Corrective lenses

Nocorrec- Contacttive Eyeglasses lenseslenses Total

only with orwithouteyeglasses


50.3

82.858.857.411.4

46.8

80.154.555.210.2

48.0

80.153.954.89.8

54.5

85.965.762.613:8

51.4

85.159.655.311.3

49.2

16.640.742.188.3

52.7

19.145.144.389.5

51.6

19.445.744.889.9

44.9

13.433.736.885.7

48.2

14.240.044.388.4

47.1

16.034.139.187.6

51.1

18.739.741.988.9

49.1

18.737.041.489.3

43.3

12.928.734.585.1

45.4

13.532.139.887.4

2.1

0.6

:::0.7

1.6

0.45.42.40.6

2.5

0.88.73.40.6

1.7

0.55.02.30.6

2.8

0.7

:::1.0

!Encludes persons for whom no information on corrective lenses was available.

NOTE : Relative standard errors of estimates for this table are found on chart onpage 33,code P4AN-M. A guide to the use of the relative standard error charts is onpage 31.

13

Table 5. Number of persons 3 years of age and over with or without corrective lenses, by type oflens , place of residence, and age: United States, 1971

[Dataarebasedonhouseholdinterviewsofthecivilian,noninstitutiondizedpopulation.Thcsuwcy design,gcneralquafifications,andinformationonthercliahilityoftheestimatesarc given in appendix I. Definitions of terms arc given in appendix 11]

Place of residence and age

ALL PLACES OF RESIDENCE

All ages 3 years and over -------

3-16 years ----------------------------17-24 years ---------------------------25-44 years ---------------------------45 years and over ---------------------

SMSA



Central city



Outside central city



OUTSIDE SMSA



Nonfarm



Farm



Persons3 years

andover’

191,602

55,78627,27547,42861,113

122,944

35,11417,77331,32238,735

55,516

14,9178,473

13,49418,633

67,428

20,1979,300

17,82820,103

68;658

20,6739,502

16,10622,378

60,711

18,3768,577

14,52819,229

7,947

2,296924

1,5783,149

INo

correc-tive

lenses

Corrective lenses

EyeglassesContact lenses

Total onlywith or without

eyeglasses

I II I


96,403

46,17716,04527,2286,952

61,157

29,00010,28917,6664,202

27,327

12,3824,9687,8532,125

33,830

16,6185,3219,8132,077

35,246

17,1785,7569,5632,750

31,381

15,295; ,M;

2:350

3,865

1,882612971400

94,284

9,24911,11419,97853,944

61,156

5,8547,416

13,49534,390

27,870

2,4093,4645,562

16,435

33,286

3,4453,9527,933

17,956

33,129

3,3953,6986,482

19,553

29,081

2,9873,3935,883

16,817

4,048

408305599

2,737

90,313

8,9209,306

18,55553,532

58,271

5,6256,149

12,40134,096

26,703

2,3332,9265,136

16,308

31,568

3,2923,2237,265

17,788

32,042

3,2963,1576,154

19,436

28,065

2,8982,8875,567

16,713

3,976

398270587

2,723

1Includes persons for whom no information on corrective lenses was available.

3,972

3291,8081,423

412

2,884

2291,2671,094

294

1,718

153729668167

1:,087

100542329117

1,,015

5::316103

72

NOTE: Relative standard errors of estimates for this table are found on chart on page32, codeA4AN . A guide to the use of the relative standard error charts is on page 31.

14

Table 6. Percent distribution of persons 3 years of age and over with or without corrective lensesby type of lens, according to place of residence and age: United States, 1971

[Data are based on household interviews of the civilian, noninstitutionafizcd population. The survey design,general qualifications, and information onthe reliability of the estimatesarc given inappendixI.Definitionsoftcnnsaregivenh appendixII]

Place of residence and age

ALL PLACES OF RESIDENCE

All ages 3 years and over-------

3-16 years----------------------------17-24 years---------------------------25-44 years---------------------------45 years and over---------------------

SMSA



Central city



Outside central city



OUTSIDE SMSA



Nonfann



Farm



Corrective lenses?ersons No) years correc-and tiveoverl lenses Eyeglasses Contact lenses

Total only with or withouteyeglasses

100.0

100.0100.0100.0100.0

100.0

100.0100.0100.0100.0

100.0

100.0100.0100.0100.0

100.0

100.0100.0100.0100.0

100.0

100.0100.0100.0100.0

100.0

100.0100.0100.0100.0

100.0

100.0100.0100.0100.0

50.3

82.858.857.411.4

49.7


82.657.956.410.8

49.2

83.058.658.211.4

50.2

82.357.255.010.3

51.3

83.160.6;;.;

.

51.7

83.260.059.112.2

48.6

82.066.261.512.7

49.2

16.640.742.188.3

49.7

16.741.743.188.8

50.2

16.140.941.288.2

49.4

17.142.544.589.3

48.3

16.438.940.287.4

47.9

16.339.640.587.5

50.9

17.833.038.086.9

47.1

16.034.139.187.6

47.4

16.034.639.688.0

48.1

15.634.538.187.5

46.8

16.334.7;:.;

.

46.7

15.933.238.286.9

46.2

15.8:;.;

86:9

50.0

17.329.237.286.5

llncludes persons for whom no information on corrective lenses was available.

2.1

0.6

::;0.7

2.3

0.7

H0.8

2.1

0.56.33.20.7

2.5

0.8

<:;0.8

1.6

0.55.72.00.5

1.7

0.55.92.20.5

0.9

3.:**

NOTE: Relative standard errors of estimates for this table are found on chart on page 33, codeP4AN-M. A guide to the use of the relative standard error charts is on page 31.

15

Table 7. Number of persons 3 years of age and over with or without corrective lenses,by type of lens, color, and age: United States, 1971

[Dataare based on household interviews of the civilian, noninstitutionalized population. The survey design, generaf qualifications, andinformation on the reliability of the estimates are given in appendix I. Definitions of terms are given in appendix II]

Color and age

Total



White



All other



Persons3 yearsand

over 1

191.602

55,78627,27547,42861,113

168,174

47,12123,65741,88455,512

23,428

8,6653,6175,5455,601

Nocorrec-tive

lenses

Corrective lenses

II I Contact

Eyeglasses lensesrotal



96.403

46,17716,04527,2286,952

80,961

“38,57613,45823,5425,385

15,442

7,6012,5873,6861,567

94.284

9,24911,11419,97853,944

86,422

8,23010,10518,14849,939

7,862

1,0191,0091,8304,005

90,313

8,9209,306

18,55553,532

82.600

7,9148,349

16,78549,552

7,713

1,006957

1,7703,980

3,972

3291,8081,423412

3,822

3161,7561,363

387

149

5;60+<



16

Table 8. Percent distribution of persons 3 years of age and over with or without cor-rective lenses by type of lens, according to color and age: United States, 1971

[Dataarebasedonhouseholdinterviewsofthecivilian,noninstitutionakzedpopulation.Thesurveydesign,generdqu.lific.tion%adinformationonthereliabilityoftheestimatesaregiveninappendixI.DefinitionsoftermsaregiveninappendixII]

Color and age

Total


3-16 years---------------------17-.24years--------------------25-44 years--------------------45 years and over--------------

White



All other



Persons3 Y12#

over 1

100.0

100.0100.0100.0100.0

100.0

100.0100.0100.0100.0

100.0

100.0100.0100.0100.0

No2orrec-tiveLenses

Corrective lenses

II I Contact

Eyeglasseslenses

Total only with orwithout

II ] eyeglasses


50.3

82.858.857.411.4

48.1

81.956.956.29*7

65.9

87.771.566.528.0

49.2

16.640.742.188.3

51.4

17.542.743.390.0

33.6

11.827.933.071.5

47.1

16.034.139.187.6

49.1

16.835.340.189.3

32.9

11.626.531.971.1

2.1

0.66.6

2.3

0.77.43.30.7

0.6

*1.41.1

*


NOTE: Relative standard errors of estimates for this table are found on chart onpage33, code I?4AN-M. A guide to the use of the relative standard error charts is onpage 31.

17

Table 9. Number of persons 3 years of age and over with or without corrective lenses,by type of lens, family income, and age: United States, 1971

[Data are based on household interviews of the civilian, noninstitutionalized population. The survey design, general qualifications, andinformation onthercliabilityof tllccstimatcs arcgiven inappendix I. Definitions oftemsare @veninappendix II]

Family income and age

All incomes2



Less than $5,000


3-16 years---------------------17-24 years--------------------2.5-44years--------------------45 years and over--------------

$5,000-$9,999



$10,00,0-$14,999



$15,000 or more



1Persons No3 years correc-

and tiveover * lenses

191,602

55,78627,27547,42861,113

38,765

8,6086,4315,554

18,172

60,185

18,1789,13015,71717,161

46,045

15,3135,719

14,16710,846

34,435

10,4474,3399,517

10,132

-.

Corrective lenses

Contact


=4===46.17716;04527,2286,952

9,24911,11419,97853,944

7,4923,9593,6152,303

32,149

1,0562,4441,907

15,797

27.764

15,163 2,8945,508 3,5809,435 6,2162,043 15,073

24,571 I 21,267

12,558 2,6723,143 2,5547,817 6,2871,054 9,753

16,554 I 17,744

8,298 2,0952,412 1,9134,893 4,589

952 9,147

90,313 3,972

8,920 3299,306 1,808

18,555 1,42353,532 412

20,665 / 539

1,0362,0791,840

15,710

26,768

2,8343,1215,839

14,975

20,166

2,5822,0845,8359,666

16,603

996.—

99

1,100

4%45288

1,141——

139437465101

~Includes persons for whom no information on corrective lenses was available.Includes unknown income.

NOTE : Relative standard errors of estimates for this table are foundpage 32, code A4AN. A guide to the use of the relative standard errorpage 31.

on chart oncharts is on

18

Table 10. Percent distribution of persons 3 years of age and over with or without cor-rective lenses by type of lens,according to family income and age: United States, 1971

[D.t.arcbasedonhouseholdinterviewsofthecivilian,noninstitutionfizedpopulation.Thesurveydesign,generalqualifications,andinformationonthereliabilityoftheestimatesaregiveninappendi:L DefinitionsoftermsaregiveninappendixII]

Corrective lenses

II I?ersons) yearsand

over 1

Nocorrec-tive

lenses

II I ContactFamily income and age

Total LEyeglassesonly

lenseswith orwithouteyeglasses

Percent distributionAll incornesz

All ages 3 years and over- 100.0 50.3 49.2 47.1

16.034.139.187.6

2.1

:::3-16 years---------------------17-24 years--------------------25-44 years--------------------45 years and over--------------

100.0100.0100.0100.0

100.0

82.858.857.411.4

44.8

16.640.742.188.3

54.7

3.00.7

Less than $5,000

All ages 3 years and over- 53.3 1.4


$5,000-$9,999


100.0100.0100.0100.0

100.0

100.0100.0100.0100.0

100.O

100.0100.0100.0100.0

100.0

100.0100.0100.0100.0

87.061.665.112.7

53.4

12.338.034.386.9

46.1

12.0 *32.333.186.5

44.5

15.6

1.7

0.3

;:;0.6


$10,000-$14,999


83.460.360.011.9

53.4

15.939.239.587.8

46.2

34.237.287.3

43.8 2.4


$15,000 or more


82.055.055.29.7

48.1

17.444.744.489.9

51.5

16.936.441.289.1

:::3.20.8

48.2 3.3


79.455.65;.:

.

20.144.148.290.3

18.734.043.389.3

J:;4.91.0

lIncludes persons for whom no information on corrective lenses was available.21ncludes unknown income.

NOTE : Relative standard errors of estimates for this table are found on chart onpage33, code P4AN-M. A guide to the use of the relative standard error charts is onpage 31.

19

Table 11. Number of persons 3 years of age and over with or without corrective lenses,by type of lens, education of head of family, and age: United States, 1971

[Data are based un household interviews of the civilian, noninstitutionalized population. The survey design, .gcncral qualifications, andinforrnauon on the reliability of the estimates are given in appendix I. Definitions of terms are given in appendix II]

Education of head offamily and age

All educations]. levelsz

All ages 3 yezrs and over-

3-16 years----------------------17-24 years------------=---------25-44 years---------------------45 years and over---------------

Less than 9 vears



9-11 years



12 vears



13 years or more



Persons3 yearsand

overl

Nocorrec-tive

lenses

191.602

55,78627,27547,42861,113

44,957

11,0034,6397,257

22,058

33,050

10,2894,9127,541

10,308

61,167

19,2389,748

16,74015,441

49,377

14,4537,59015,28612>0/+8

Corrective lenses

Contact

Eyeglasses lensesTotal only with or

withouteyeglasses


96,403

;:,;L7;

27;2286,952

20,487

9,3633,2764,8303,017

173762

8,5813,2074,8201,154

32,823

15,8415,5749,8761>532

23,762

11,7163,7297,3151,001

94,284

9,24911,11419,97853,944

24,252

1,5561,3442,381

18,971

15,126

1,6391,6762,6959,116

28,064

3,2854,1376,801

13,841

25,429

2,6643,8397,911

11,016

90.313

8,9209,306

18,55553,532

24,010

1,5391,2602,337

18,874

14,755

1,5961,5142,5939,052

26,746

3,1723,4796,377

13,718

23,413

2,5172,9427,060

10,893

3.972

3291,8081,423412

241

-2

844497

370

4416110264

1,318

114658424123

2,017

147897851123

~Includes persons for whom no information on corrective lenses was available.‘Includes ~nknown education.


20

Table 12. Percent distribution of persons 3 years of age and over with or without cor-rective lenses by type of lens, according to education of head of family and age:United States, 1971

[Data are based on household interviews of the civilian, noninstitutionalized population. The survey desi~, general qualifications, andinformation on the reliability of the estimates are given in appench I. Definitions of terms are given in appendix II]

Education of head offamily and age

All educational levels2


3-16 years---------------------1,7-24years--------------------25-44 years--------------------45 years and over--------------

Less than 9 years



9-11 years



12 years



13 years or more



II I

II I Corrective lenses

Persons No3 years correc-and tiveover 1 lenses

r

Total

I Contact

Eyeglasseslenses

only with orwithouteyeglasses

100.0

100.0100.0100.0100.0

100.0

100.0100.0100.0100.0

100.0

100.0100.0100.0100.0

100.0

100.0100.0100.0100.0

100.0

100.0100.0100.0100.0


7750.3 49.2

82.8 16.658.8 40.757.4 42.111.4 88.3

45.6 I 53.91

85.1 14.170.6 ;;.;66.61&3.7 86:0

53.7 I 45.8I

83.4 15.965.3 34.163.9 35.711.2 88.4

53.7 45.9

82.3 17.157.2 42.459.0 40.69.9 89.6

X!JdJ-J

81.1 18.449.1 50.647.9 51.88.3 91.4

47.1 I 2.1I

16.0 0.634.1 6.639.187.6 :::

53.4 I 0.5

14.027.2 1.:32.2 0.685.6 0.4

T44.6 1.1

15.5 0.430.834.4 ?::87.8 0.6

43.7 I 2.2

16.535.738.188.8

0.66.82.50.8

mlIncludes Dersons for whom no information on corrective lenses was available.z~ncludes &&nown education.

NOTE :page 33,page 31.

Relative standard errors of estimates for this table are found on chart oncode P4AN-M. A guide to the use of the relative standard error charts is on

21

Table 13. Nu, r of persons 17 years of age and over with or without corrective lenses,by ty, of lens, education of individual, and age: United States, 1971

[Data are based on! :,lsehold interviews of thecivilian, nonirlstitutionalized population. Thesuwey desi~, general quaIifimtions, mdinformation on the reliabilityof theestimates arc given in appendix I. Definitions of terms aregiven inappendix II]

Education of individualaud age

All educational levelsz

All ages 17 years and over--

17-24 years--------------------25-44 years--------------------45 years and over--------------

Less than 9 years



9-11 years



12 years


17-24 years--------------------25-44 years--------------------45 years and cer--------------

13 vears or more


17-24 years--------------------25.44 years--------------------45 years and over--------------

TPersons No17 years correc-and tiveover I lenses

135,815

27,27547,42861,113

28,075

1,3755,438

21,262

26,111

7,5387,999

10,573

47,466

10,64619,68017,140

31,534

7,11613,70210,717

Corrective lenses

Contact

Eyeglasses lensesTotal



50,225

16,04527,2286,952

8,017

1,1553,8992,962

11,463

5,0515,2461,166

19,159

6,19011,2941,675

10,525

3,2726,411

842

85.035

11,11419,97853,944

19,937

2061,496

18,234

14,537

2,4532,7249,360

28,123

4,4118,30615,407

20,918

3,8317,2459,842

81,393 I 3,643

9,306 1,80818,555 1,42353,532 412

I19,826 111

I

2021,477

18,147

*

8;

14,169 I 368

2,214 2392,656 689,298 62

I26,800 1,323

13,7937,746

15,261

618560146

I

19,123 1,795

2,9116,4789,733

919767109

!Includes persons for whom no information on corrective lenses was available.‘Includes finknown education.


22

Table 14, Percent distribution of persons 17 yearsof age and over with ithout cor-rective lenses by type of lens, according to education of indi~idual a age: UnitedStates, 1971

[D.nmebasedonhouseholdintemiewsoftietivilia,notinstitutiontizedpoptiation.TheSU~~eyde~wl,gClllqu~lifi=tions,andinformation on the reliability of the estimates are given in appendix I. Definitions of *mms are given i. ippendix II]

II I

Education of individualand age

All educational levels2


17.24 years---------------------25-44 years---------------=-----45 years and over---------.=----

Less than 9 years


17-24 years------=--------------25-44 years=--------------------45 years and over---------------

9-11 years


17-24 years---------------------25-44 years---------------------45 years and over---------------

12 years



13 years or more


17-24 years---------------------25-44 years---------------------45 years and over ---------------

‘“1SK-FE

PersonsL7 years

100.0

100.0100.0100.0

100.0

100.0100.0100.0

100.0

100.0100.0100.0

100.0

100.0100.0100.0

100.0

100.0100.0100.0


37.0

58.857.411.4

28.6

84.071.713.9

43.9

67.065.611.0

40.4

58.157.4

9.8

33.4

46.046.8

7.9

+}

40.7 3k.L42.1 39.188.3 87.6

71.0 70.6

15.0 14.727.5 27.285.8 85.3

Ir55.7 54.3

32.5 29.434.1 33.288.5 87.9

59.2 56.5

41.4 35.642.2 39.489.9 89.0

66.3 60.6

53.8 40.952.9 47.391.8 90.8

2.7

6.63.00.7

0.4

%

0.:

1.4

3.20.90.6

2.8

H0.9

5.7

12.95.61.0

~Includes persons for whom no information on corrective lenses was available.Includes unknown education.


23

Table 15. Number of persons 17 years of age and overin the labor force with or withoutcorrective lenses, by type of lens, occupation class, and age: United States, 1971

[Data are based on household interviews of the .n ili,i],, nrminstitutionalized population. The survey design, general qualifications, andinformation on the reliability of the estimates are given in appendix I. Definitions of terms are given in appendix II]

Occupation class and age

All occupation classesz

All ages 17 years and over..


White-collar workers



Blue-collar workers


17-24 years---------------------25-44 years ---------------------45 years and over---------------

Service workers

All ages 1.7years and over--


Farm workers



Persons17 years

andoverl

Nocorrec-tive

lenses Total

;orrective lenses

EEyeglassesonly


17,734 10,45933,697 19,43231,640 3,977

=---l 1“7836,704 3,207

15,866 7,44513,697 1,131

6,149 4,32011,986 8,37510,338 1,720

T11,052 4,454

2,845 1,6863,527 2,1314,680 637

2,684 II 1,210

427797

1,461

299596316

48,892

7,21414,12927,549

24,350

3,4788,363

12,509

13,958

1,8043,5688,586

6.551

1,1511,3724,028

1,459

124197

1,139

Contactlenses

with orwithouteyeglasses

46,536 I 2,356

I6,045 1,16913,153 97727,338 211

.22>740I 1,6111

2,7437,596

12,401

735767108

13,650 I 308

1,6453,4768,529

1609257

*

6,303 248

994 1571,305 674,004 >k

1,433

109 ;’<194 $<

1,130 ;!<

!Includes Dersons for whom no information on corrective lenses was available.‘Includes ;nknown occupation.


24

Table 16. Percent distribution of persons 17 years of age and over in the labor forcewith or without corrective lenses by type of lens, according to occupation class andage: United States, 1971

[Dataarebasedonhouseholdinterviewsofthecivilian,noninstitutionafizedpopulation.Thesuey dcsign,generalqwdifications,andinformationonthereliabilityoftheestimatesaregiveninappendixI.DefinitionsoftermsaregiveninappendixII]

Occupation class and age

Corrective lenses

Nocorrec- Contacttive

Eyeglasseslenses

lenses Total only with orwithout

eyeglasses

Persons17 years

andoverl

All occupation classes2



100.0 I 40.8 58.9 2.8

I100.0100.0100.0

100.0

100.0100.0100.0

100.0 I

17-24 years---------------------25-44 years---------------------45’years and over---------------

59.057.712.6

32.5

47.846.98.3

50.6

40.741.987.1

67.1

34.139.086.4

62.7


All ages 17 years and over-- 4.4

17-24 years----------------------25-44 years---------------------45 years and over---------------

51.952.791.3

49.0

40.947.990.5

11.04.80.8

Blue-collar workers

All ages 17 years and over-- 47.9

26.8;2.;

.

1.1


100.0100.0100.0

100.0

70.369.916.6

40.3

29.3;2.:

59.3

2.60.80.6

Service workers

All ages 17 years and over-- 57.0 2.2

4100.0100.0100.0

100.0

100.0100.0100.0

17-24 years---------------------25-44 years-=-------------------45 years and over---------------

59.360.413.6

45.1

70.074.821.6

40.538.986.1

54.4

I 34.9 5.51.9*

37.085.6

Farm workers

All ages 17 years and over-- *


29.024.778.0

25.524.377.3

***

~Includes persons for whomno information on corrective lenses was available.Includes unknown occupation.


25

APPENDIX 1

TECHNICAL NOTES ON METHODS

Background of This Report

This report is one of a series of statisticalreports prepared by the National Center forHealth Statistics (NCHS). It is based on infor-mation collected in a continuing nationwidesample of households in the Health InterviewSurvey (HIS).

The Health Interview Survey utilizes aquestionnaire which obtains information on per-sonal and demographic characteristics, illnesses,injuries, impairments, chronic conditions, andother health topics. As data relating to each ofthese various broad topics are tabulated andanalyzed, separate reports are issued which coverone or more of the specific topics. The presentreport is based on data Collected in householdinterviews during 1971.

The population covered by the sample forthe Health Interview Survey is the civilian, non-institutionalized population of the United Statesliving at the time of the interview. The sampledoes not include members of the Armed Forcesor U.S. nationals living in foreign countries. Itshould also be noted that the estimates showndo not represent a complete measure of anygiven topic during the specified calendar periodsince data are not collected in the interview forpersons who died during the reference period.For many types of statistics collected in the sur-vey, the reference period covers the 2 weeksprior to the interview week. For such a shortperiod, the contribution by decedents to a totalinventory of conditions or services should bevery small. However, the contribution by de-cedents during a long reference period (e.g., 1year) might be sizable, especially for olderpersons.

Statistical Design of theHealth Interview Survey

General plarz.-The sampling plan of thesurvey follows a multistage probability designwhich permits a continuous sampling of thecivilian, noninstitutionalized population of theUnited States. The sample is designed in such away that the sample of households interviewedeach week is representative of the target popula-tion and that weekly samples are additive overtime. This feature of the design permits bothcontinuous measurement of characteristics ofsamples and more detailed analysis of less com-mon characteristics and smaller categories ofhealth-related items. The continuous collectionhas administrative and operational advantages aswell as technical assets since it permits fieldworkto be handled with an experienced, stable staff.

The overall sample was designed so thattabulations can be provided for each of the fourmajor geographic regions and for urban and ruralsectors of the United States.

The first stage of the sample design consistsof drawing a sample of 357 primary samplingunits (PSU’S) from approximately 1,900 geo-graphically defined PSU’S. A PSU consists of acounty, a small group of contiguous counties, ora standard metropolitan statistical area. ThePSU’S collectively cover the 50 States and theDistrict of Columbia.

With no loss in general understanding, theremaining stages can be combined and treated inthis discussion as an ultimate stage. WithinPSU’S, then, ultimate stage units called segmentsare defined in such a manner that each segmentcontains an expected six households. Three gen-eral types of segments are used.

26

Area segments

List segments,frame.

which are defined geographically.

using 1960 census registers as the

Permit segments, using updated lists of buildingpermits issued in sampIe PSU’S since 1960.

Census address listings were used for all areas ofthe country where addresses were well definedand could be used to locate housing units. Ingeneral the list frame included the larger urbanareas of the United States from which abouttwo-thirds of the HIS sample was selected.

The usual HIS sample consists of approxi-mately 8,000 segments containing 57,000 as-signed households, of which 11,000 were vacant,demolished, or occupied by persons not in thescope of the sun’ey. The 46,000 eligible oc-cupied households yield a probability sample ofabout 134,000 persons in 44,000 interviewedhouseholds in a year.

Descriptive material on data collection,field procedures, and questionnaire developmentin the HIS has been published 3 as well as a de-tailed description of the sample design4 and areport on the estimation procedure and themethod us”ed to calculate sampling errors of esti-mates derived from the survey.

CoUection of data. –Field operations forthe survey are performed by the U.S. Bureau ofthe Census under specifications established bythe National Center for Health Statistics. In ac-

3National Center for Health Statistics: Healthsurvey procedure: concepts, questionnaire development,and definitions in the Health Interview Survey. Vital andHealth Statistics. PHS Pub. No. 1000-Series l-No. 2.Public Health Service. Washington. U.S. GovernmentPrinting Office, May 1964.

4U s Nation~] He~~ survey: The statistic~ de-. .sign of the health household interview survey. HealthStatistics. PHS Pub. No. 584-A2. Public Health Service.Washin on, D.C., July 1958.

!! National Center for Health Statistics: Esti-mation and sampling variance in the HeaIth InterviewSurvey. Vital and Health Statistics. H-K Pub. No.

1000-Series 2-No. 38. Public Health Service. Washington.U.S. Government Printing Office, June 1970.

cordance with these specifications the Bureau of

the Census participates in survey planning, se-

lects the sample, and conducts the field kter-

viewing as an agent of NCHS. The data are

coded, edited, and tabulated by NCHS.Estimating procedures. – Since the design of

the HIS is a complex multistage probabilitysample, it is necessary to use complex pro-cedures in the derivation of estimates. Fourbasic operations are involved:

1.

2.

3.

4.

to

Inflation by the reciprocal of the probabilityof selectiorz. -The probability of selection isthe product of the probabilities of selectionfrom each step of selection in the design(PSU, segment, and household).

Nonresponse adjustment. –The estimates areinflated by a multiplication factor which hasas its numerator the number of sample house-holds in a given segment and as its denomina-tor the number of households interviewed inthat segment.

First-stage ratio adjustment. –Samplingtheory indicates that the use of auxiliary in-formation which is highly correlated with thevariables being estimated improves the re-liability of the estimates. To reduce the vari-ability between PSU’S within a region, theestimates are ratio adjusted to the 1960populations within six color-residence classes.

Poststratification b? age-sex -co/or. –The esti-mates are ratio adjusted within each of 60age-sex-color cells to an independent estimateof the population of each cell for the surveyperiod. These independent estimates are pre-pared by the Bureau of the Census. Both thefirst-stage and poststratified ratio adjust-ments take the form of multiplication factorsapplied to the weight of each elementary unit(person, household, condition, andhospitalization).

The effect of the ratio-estimating process ismake the samde more closely representative.

of the civilian, noninstitutiordzed- populationby age-, sex, color, and residence, which therebyreduces sampling variance.

27

As noted, each week’s sample representsthe population living during that week and char-acteristics of the population. Consolidation ofsamples over a time period, e.g., a calendarquarter, produces estimates of average character-istics of the U.S. population for the calendarquarter. Similarly, population data for a year areaverages of the four quarterly figures.

For prevalence statistics, such as number ofpersons with speech impairments or number ofpersons classified by time interval since lastphysician visit, figures are first calculated foreach calendar quarter by averaging estimates forall weeks of interviewing in. the quarter. Prev-alence data for a year are then obtained byaveraging the four quarterly figures.

For other types of statistics–namely thosemeasuring the number of occurrences during aspecified time period-such as incidence of acuteconditions, number of disability days, or num-ber of visits to a doctor or dentist, a similarcomputational procedure is used, but the statis-tics are interpreted differently. For these items,the questionnaire asks for the respondent’s ex-perience over the 2 calendar weeks prior to theweek of interview. In such instances the esti-mated quarterly total for the statistic is 6.5times the average 2-week estimate produced bythe 13 successive samples taken during theperiod. The annual totaI is the sum of the fourquarters. Thus the experience of persons inter-viewed dzm”ng a y ear–experience which actuallyoccurred for each person in a 2-caIendar-weekinterwd prior to week of interview—is treated asthough it measured the total of such experienceduring the year. Such interpretation leads to nosignificant bias.

General Qualifications

Nonresponse. –Data were adjusted for non-response by a procedure which imputes to per-sons in a household which was not interviewedthe characteristics of persons in households inthe same segment which were interviewed. Thetotal noninterview rate, the ratio of the totalnoninterviewed eligible households to the totaleligible households, was 3.6 percent, including a1. l-percent refusal rate with the remainder pri-

marily due to the failure to find an eligible re-spondent at home after repeated calls.

The interview process. –The statistics pre-sented in this report are based on replies ob-tained in interviews with persons in the samplehouseholds. Each person 19 years of age andover present at the time of interview was inter-viewed individually. For children and for adultsnot present in the home at the time of the inter-view, the information was obtained from a re-lated househoId member such as a spouse or themother of a child.

There are limitations to the accuracy ofdiagnostic and other information collected inhousehold interviews. For diagnostic infor-mation, the household respondent can usuallypass on to the interviewer only the informationthe physician has given to the family. For condi-tions not medically attended, diagnostic infor-mation is often no more than a description ofsymptoms. However, other facts, such as thenumber of disability days caused by the condi-tion, can be obtained more accurately fromhousehold members than from. any other sourcesince only the persons concerned are in a posi-tion to report this information.

Rounding of numbers. –The original tabula-tions on which the data in this report are basedshow all estimates to the nearest whole unit. Allconsolidations were made from the originaltabulations using the estimates to the nearestunit. In the final published tables, the figures arerounded to the nearest thousand, although theseare not necessarily accurate to that detail. De-vised statistics such as rates and percent distri-butions are computed after the estimates onwhich these are based have been rounded to thenearest thousand.

Population figures. –Some of the publishedtables include population figures for specifiedcategories. Except for certain overall totals byage, sex, and color, which are adjusted to in-dependent estimates, these figures are based onthe sample of households in the HIS. These aregiven primarily to provide denominators for ratecomputation, and for this purpose are more ap-propriate for use with the accompanying meas-ures of health characteristics than other popula-tion data that may be avaiIabIe. With the excep-tion of the overall totals by age, sex, and color

28

mentioned above, the population figures differfrom figures (which are derived from differentsources) published in reports of the Bureau ofthe Census. Official population estimates arepresented in Bureau of the Census reports inSeries P-20, P-25, and P-60.

Reliability of Estimates

Since the statistics presented in this reportare based on a sample, they will differ somewhatfrom the figures that would have been obtainedif a complete census had been taken using thesame schedules, instructions, and interviewingpersonnel and procedures.

As in any survey, the results are also sub-ject to reporting and processing errors and errorsdhe to nonresponse. To the extent possible,these types of errors were kept to a minimum bymethods built into survey procedures. Althoughit is very difficult to measure the extent of biasin the Health Interview Survey, a number ofstudies have been conducted to study this prob-lem. Thf ,~esults have been published in severalreports. -

6 Na~ion~l center for Health Statistics:Reportingof hospitalization in the Health Interview Survey. Vitaland Health Statistics. PHS Pub. No. 1000-Series2-No.6.Public Health Service. Washington. U.S. GovernmentPrintingOffice, July 1965.

7NationalCenter for HealthStatistics:Health in-terview responses compared with medical records. Vitaland Health Statistics. PHS Pub. No. 1000-Series2-No. 7.Public Health Service. Washington. U.S. GovernmentPrinting Office, July 1965.

*National Center for Health Statistics: Compari-son of hospitalization reporting in three survey proce-dures. Vital and Health Statistics. PHS Pub. No.1000-Series2-No. 8. Public Health Service.Washington.U.S. GovernmentPrintingOffice, July 1965.

9National Center for Health Statistics: Interview

data on chronic conditions compared with informationderived from medical records. Vital and HealthStatistics. PHS Pub. No. 1000-Series2-No. 23. PublicHealth Service. Washington.U.S. Government PrintingOffice, May 1967.

10Nationfl Center for Health Statistics: The blflu-ence of interviewer and respondent psychological andbehavioral variables on the reporting in household inter-views. Vital and Health Statistics. PHS Pub. No.1000-Series 2-No. 26. Public Health Service. Washington.U.S. Government Printing Office, Mar. 1968.

The standard error is primarily a measureof sampIing variability, that is, the variationsthat might occur by chance because only asample of the population is surveyed. As calcu-lated for this report, the standard error ak.o re-flects part of the variation which arises in themeasurement process. It does not include esti-mates of any biases which might be in the data.The chances are about 68 out of 100 that anestimate from the sample would differ from acomplete census by less than the standard error.The chances are about 95 out of 100 that thedifference would be less than twice the standarderror and about 99 out of 100 that it would beless than 2Y2 times as Iarge.

The relative standard error of an estimate isobtained by dividing the standard error of theestimate by the estimate itself and is expressedas a percentage of the estimate. For this report,asterisks are shown for any cell with more than a30-percent relative standard error. Included inthis appendix are charts from which the relativestandard errors can be determined for estimatesshown in the report. In order to derive relativeerrors which would be applicable to a wide vari-ety of health statistics and which could be pre-pared at a moderate cost, a number of approxi-mations were required. As a result, the chartsprovide an estimate of the approximate relativestandard error rather than the precise error forany specific aggregate or percentage.

Three classes of statistics for the health sur-vey are identified for purposes of estimatingvariances.

A’arrow range. –This class consists of (1) sta-tistics which estimate a population attribute,e.g., the number of persons in a particular in-come group, and (2) statistics for which themeasure for a singIe individual during the refer-ence period used in data collection is usuallyeither O or 1 or on occasion may take on thevalue 2 or very rarely 3.

Medium range. –This cIass consists of other sta-tistics for which the measure for a single indi-vidual during the reference period used in datacollection will rarely lie outside the range O to 5.

Wide range. –This class consists of statistics forwhich the measure for a single individual during

29

the reference period used in data collection canrange from O to a number in excess of 5, e.g.,the number of days of bed disability.

In addition to classifying variables accord-ing to whether they are narrow-, medium-, orwide-range, statistics in the survey are furtherdefined as:

Type xl. Statistics on prevalence and incidencefor which the period of reference in thequestionnaire is 12 months.

T~,pe B. Incidence-type statistics for which theperiod of reference in the questionnaireis 2 weeks.

Type C. Statistics for which the re-ference pe-riod is 6 months.

Only the charts on sampling error appli-cable to data contained in this report arepresented.

Genera[ rules jor determining relative sam-pling errors.-The “guide” on page 31, to-gether with the following rules, will enable thereader to determine approximate relative stan-dard errors from the charts for estimates pre-sented in this report.

Rule 1.

Rule 2.

Rule 3.

30

Estimates of aggregates: Approximaterelative standard errors for estimates ofaggregates such as the number of per-sons with a given characteristic are ob-tained from appropriate curves onpage 32. The number of persons inthe total U.S. population or in an agc-sex-color class of the total population isadjusted to official Bureau of the Cen-sus figures and is not subject to sam-pling error.Estimates of percentages in a percentdistribution: Relative standard errorsfor percentages in a percent distributionof a total are obtained from appropriatecurves on page 33. For values whichdo not fall on one of the curves pre-sented in the chart, visual interpolationwill provide a satisfactoryapproximation.Estimates of rates where the numeratoris a subclass of the denominator: This

Rule 4.

rule applies for prevalence rates orwhere a unit of the numerator occurs,with few exceptions, only once in theyear for any one unit in the denomi-nator. For example, in computing therate of visual impairments per 1,000population, the numerator consisting ofpersons with the impairment is a sub-class of the denominator, which in-cludes all persons in the population.Such rates if converted to rates per 100may be treated as though they were per-centages and the relative standard errorsobtained from the chart P4AN-M. Ratesper 1,000, or on any other base, mustfirst be converted to rates per 100; thenthe percentage chart will provide therelative standard error per 100.

Estimates of rates where the numeratoris not a subclass of the denominator:This rule applies where a unit of thenumerator often occurs more than oncefor any one unit in the denominator.For example, in the computation of thenumber of persons injured per 100 cur-rently employed persons per year, it ispossible that a person in the denomi-nator could have sustained more thanone of the injuries included in the nu-merator. Approximate relative standarderrors for rates of this kind may becomputed as follows:

-1

(a)

(b)

Where the denominator is the totalU.S. population or includes all per-sons in one or more of the age-sex-color groups of the total popu-lation, the relative error of the rateis equivalent to the relative error ofthe numerator, which can be ob-tained directly from the appro-priate chart.In other cases the relative standarderror of the numerator and of thedenominator can be obtained fromthe appropriate curve. Square eachof these relative errors, add the re-sulting values, and extract thesquare root of the sum. This pro-cedure will result in an upper

bound on the standard error and of-ten will overstate the error.

Rule 5. Estimates of difference between twostatistics (mean, rate, total, etc.): Thestandard error of a difference is approx-imately the square root of the sum ofthe squares of each standard error con-sidered separately. A formula for thestandard error of a difference,

d = .Y1 – .Y2

is

2 + (.Y2 17X2)2

where Xl is the estimate for class 1, X2

is the estimate for class 2, and VX ~ and

v~a are tb.e reIative errors of Xl and

X2 re sp ectiveIy. This formula will

represent the actual standard error quiteaccurately for the difference betweenseparate and uncorrelated character-istics although it is ordy a rough approx-imation in most other cases. The rela-tive standard error of each estimateinvolved in such a difference can be de-termined by one of the four rulesabove, whichever is appropriate.

Guide to Use of Relative Standard Error Charts

The code shown below identifies the ap- (1) A = aggregate, P = percentage; (2) the num-propriate curve to be used in estimating the rela- ber of calendar quarters of data collection; (3)tive standard error of the statistic described. The the type of statistic as described on page 30; andfour components of each code describe the sta- (4) the range of the statistic as described ontistic as follows: page 29-30.

I Use:

Statistic

Rule Code On page

Number of:

Persons in the U.S. population or total number of persons in any age-

sex category . . . . . . . . . . . . . . . . . Not subject to sampl ing error

Persons in any other population group . . . . . . . . . . 1 I A4AN I 32

Persons with corrective lenses . . . . . . . . . . . . . I1 I A4AN I 32

Percent distribution of:Persons with corrective lenses by characteristic . . . . . . . . 2 P4AN-M 33

31

Relative standard errorq for aggregates based on four quxrixrs of dlrta coUkctiOnfor data of &U. types and ranges

Size of estimate (in thousands)

Example of use of chart: An aggregate of 2,000,000 (on scale at bottom of chart) for aNarrow range Type A statistic (code: A4AN) has a relative standard error of 3.6 percent,(read from scale at left side of chart), or2,000,000) .

a standard error of 72,000 (3.6 percent ofFor a Wide range Type B statistic (code: A4BW), an aggregate of 6,000,000 has

a relative error of 16.0 percent or a standard error of 960,000 (16 p.arcent of 6,000,000).

3.2

Pd.ativsatandara errorsfor percentagesbased cm four gmrtera of dsta collectionfor typeA data, Narrow and Wiuxa range

(13me of percentage shown on curves In intUions)

Eatimt ed percentage

Example of use of dart: An estimte of 20 percent (on scale at bottan of chart) based onsn esthnwte of 10$OCO,CXXI has a reJAive standsrd error of 3.2 pereent (rasd frm thescale at the left side of the okrt), Ws point at which the curve for a base of 10,OOO,Wtitersmts the vertkal ltie for Xl percent. 5e steadiwd error h percentage points isequel to 20 pereent X 3.2 percent or 0.6k percentage points.

33

APPENDIX II

DEFINITIONS OF CERTAIN TERMS USED IN THIS REPORT

Corrective lenses. –Corrective lenses includeeyeglasses and contact lenses. The term is lim-ited to visual aids worn to correct or improvevision and therefore excludes sunglasses wornonly to filter light, safety glasses worn only forprotection of the eyes, hand magnifying glasses,and other such devices. However, if the safetyglasses are worn also for correction or improve-ment of vision, they are considered correctivelenses as are prescription sunglasses.

Age. –The age recorded for each person isthe age at last birthday. Age is recorded in singleyears and grouped in a variety of distributionsdepending on the purpose of the table.

Color. -The population is divided into twocolor groups, “white” and “all other. ” “Allother” includes Negro, American Indian, Chi-nese, Japanese, and any other race. Mexican per-sons are included with “white” unless definitelyknown to be Indian or of another race.

Income of family or of unrelatedirzdiuicluak–Each member of a family is classi-fied according to the total income of the familyof which he is a member. Within the householdall persons related to each other by blood, mar-riage, or adoption constitute a family. Unrelatedindividuals are classified according to their ownincome.

The income recorded is the total of all in-come received by members of the family (or byan unrelated individual) in the 12-month periodpreceding the week of interview. Income from’all sources is included, e.g., wages, salaries, rentsfrom property, pensions, and help from rela-tives.

Education. –The categories of educationstatus show the years of school completed. Onlyyears completed in regular schools, where per-sons are given a formal education, are included.A “regular” school is one which advances a per-son toward an elementary or high schooldiploma or a college, university, or professionalschool degree. Thus education in vocational,trade, or business schools outside the regularschool system is not counted in determining thehighest grade of school completed.

Education of head of family or of urwelatedindividuals. —Each member of a family is classi-fied according to the education of the head ofthe family of which he is a member. Within thehousehold all persons related to each other byblood, marriage, or adoption constitute a ~family.L1nrelated individuals are classified according totheir own education.

Education of individual. - Each person aged 17years or older is classified by education in termsof the highest grade of school compIeted.

Geographic region. – For the purpose ofclassifying the population by geographic area,the States are grouped into four regions,, Theseregions, which correspond to those used by theU.S. Bureau of the Census, are shclwn infigure I.

Place of residence. –The place of residenceof a ‘m[e.mber of the civilian, noninstitutio nalizedpopulat~on is classified as inside a standard met-ropolitan statistical area (SMSA) or outside anSMSA and either farm or nonfarm.

34

...

Reuqion

Northeast . .

North Central

South . . .

\vcst . . .

. .

. .

. .

. .

States Included

Maine. New Hampshire,Vermont, hlassachusctts,Rhode Island, Connecticut,New York, Ncw J crsey,Pennsylvania

Michigm, Ohio, Indiana,IIIinois, Wisconsin,Nlinncsota, Iowa, Missouri,North Dakota, SouthDakota, Kansas, Ncbrmka

Dclavvare, Maryland,District of Columbia,Virginia, West Virginia, INorth Carolina, SouthCarolina, Georgia, Florida,Kentucky, Texas, Tenncsscc,Alabama, itlississippi,Arkansas, Louisiana,Oklahoma

hlontana, Idaho, tVy-(Jnling,Colorado, N’cw Mcwco,Arizona, Ut till, N’cvada,Washingttm, i\lilSkil, Orcgon,(klil(wnin, IIilIv:lii

Figure 1.

Standard metropolitan statistical areas. –The def-initions and titles of SMSA’S are established bythe U.S. Office of Management and Budget withthe advice of the Federal Committee on Stand-ard Metropolitan Statistical Areas. There \vere212 SMSA’S defined for the 1960 decennialcensus.

The definition of an individual SMSA involvestwo considerations: first, a city or cities of speci-fied population which constitute the central cityand identify the county in which it is located asthe central county; second, economic and sociaIrelationships with contiguous counties (exceptin New England) which are metropolitan in char-acter so that the periphery of the specific metro-politan area may be determined. SMSA’S are not

limited by State boundaries. In New EnglandSMSA’S consist of towns and cities, rather thancounties. The metropolitan population in this re-port is based on SMSA’S as defined in the 1960census and does not include any subsequent ad-ditions or changes.

Central cities. –Each SMSA must include at leastone central city. The complete title of an SMSAidentifies the central city or cities. If only onecentral city is designated, then it must have50,000 inhabitants or more. The area title mayinclude, in addition to the largest city, up to twocity names on the basis and in the order of thefollowing criteria: (1) the additional city has atleast 250,000 inhabitants or (2) the additionalcity has. a population of one-third or more ofthat of the largest city and a minimum popu-lation of 25,000. An exception occurs wheretwo cities have contiguous boundaries and con-stitute, for economic and social purposes, asingle community of at least 50,000, the smallerof which must have a population of at least15,000.

Farm and nonfarrn residence.–The populationresiding outside SIilSA’s is subdivided into thefarm population, which comprises all non-SMSAresidents living on farms, and the nonfarm popu-lation, which comprises the remaining outsideSMSA population. The farm population includespersons living on places of 10 acres or morefrom which sales of farm products amounted to$50 or more during the previous 12 months oron places of less than 10 acres from which salesof farm products amounted to $250 or moreduring the preceding 12 months. Other personsliving outside an SMSA were classified as non-farm if their household paid rent for the housebut their rent did not include any land used forfarming.

Sales of farm products refer to the gross receiptsfrom the sale of field crops, vegetables, fruits,nuts, livestock and livestock products (milk,wool, etc.), poultry and poultry products, andnursery and forest products produced on theplace and sold at any time during the preceding12 months.

Occupation.–A person’s occupation maybe defined as his principal job or business. For

35

the purposes of this survey, the principal job orbusiness is defined in one of the following ways.If the person worked during the 2-week refer-ence period of the interview, or had a job orbusiness, the question concerning his occupation(or what kind of work he was doing) applies tohis job during that period. If the respondentheld more than one job, the question is directedto the one at which he spent the most time. Foran unemployed person, this question refers tothe last full-time civilian job he had. A personwho has a job to which he has not yet reported,and has never had a previous job or business, isclassified as a “new worker. ”

The occupation classes presented in this re-port and their code numbers as found in the

Occupation Classification


Professional, technical, and kindredworkers . . . . . . . . . .

Managers and’administrators, except farm .Sales workers . . . . . . . . .Clerical and kindred “workers . . . . .

Blue-collar workers

Craftsmen and kindred workersOperatives, except transport .Transport equipment operativesLaborers, except farm . . .

Farm workers

Farmers and farm managers .

Farm laborers and farm foremen

Service workers

. . . .

... .

... .

. . . .

. . . .

. . . .

Service workers, except private household .

Private household workers . . . . . .

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

Figure Il.

Census Cock

001-195, N

201-245260-280

301-395, P, Q

401-580, R, S

601-696, T701-715, u740-785, V

801-802, W

821-824

901-965, X, Y

980-984, Z

990,995

Classified Index of Occupations and Industriesof the U.S. Bureau of the Census are shown infigure II.

Industry .–The industry in which a personwas reportedly working is classified by the majoractivity of the establishment in which heworked. The only exceptions, the few establish-ments classified according to the major activityof the parent organization, are as follows:lab oratories, warehouses, repair shops, andstorage facilities.

The industry categories presented in this re- ,port are shown in figure III with the corre-spon ding codes found in the Classified Index ofOccupations and Industries, U.S. Bureau of theCensus, and the Standard Industrial Classifi-cation Manual (SIC), U.S. Office of Managementand Budget.

Industry Classijiication

Agriculture . . . .

Forestry and fisheries .MiningConstrucdon : : : :Manufacturing . . .Transportation and

public utilities . .Wholesale and retail

trade . .Finance, insurance, “ -

and real estate . .Services and miscel-

laneous .Public administra;io; :Unknown . . . .

Cenrus Code

017-019, A

027-028047-057067-077, B107-398, C

407-479, D

507-698, E, F, G

707-718

727-897, H, J , K907-937, L, M996-999

——

SIC Code

01,07(except 071 3)

08,0910-1415-1719-39,0713

40-49

50-59

60-67

70-8991-9499

Figure Ill.

In labor force.–AIl persons 17 years andolder who worked at or had a job or business orwere looking for work or on layoff from workduring the 2-week period prior to the week ofinterv;ew are in the-labor force.

—o o o—

36

APPENDIX 111

FORM FOR RECORDING INFORMATION ON CORRECTIVE LENSES

)70. D-s anyons in the family pa. - l. Contact lcnscs?. .Y N . . . . . . . . . 123456789~c)

If ’’Yes,” ask bandc

b. Who is this? Circle person’s number 2. EyagIassos? . . ..Y N . . . . . . . .. I 2 3 4 s 6 7 8 [, II

e. AnyoIw ●ISO?3. A hmring aid? . . . Y N . . . . . . ...1 2 3 4 5 6 - :. 9 10

For “hearing aid,” with no hemring problem rcpormd. J ..k,

For what condition &es ha need this?

Enter condition in item C

—o o o—

37

Series 1.

SeVies 2.

Series 3.

.%7ies 4.

Sevies 10.

Series 11.

Series 12.

Se7ies 13.

Series 14.

SeYies 20.

Series 21.

Series 22.

VITAL AND HEALTH STATISTICS PUBLICATION SERIES

Originally Public Health Service Publication No. 1000

Pvograms and collection procedures. — Reports which describe the general programs of the NationalCenter for Health Statistics and its offices and divisions, data collection methods used, definitions,

and other material necessary for understanding the data.

Data evaluation and methods ~eseavch. — Studies of new statistical methodology including: experi-

mental tests of new survey methods, studies of vital statistics collection methods, new analyticaltechniques, objective evaluations of reliability of collected data, contributions to statistical theory.

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

statis~’cs, carrying the analysis further than the expository types of reports in the other series.

Documents and committee vepoyts. — Final reports of major committees concerned with vital and

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

birth and death certificates.

Data porn the Health Interview .%?wev. —Statistics on illness, accidental injuries, disability, useof hospital, medical, dental, and other services, and other health-related topics, based on data

collected in a continuing national household interview survey.

Data from the Health Examination Survey. —Data from direct examination, testing, and measure-

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

of reports: (1) estimates of the medically defined prevalence of specific diseases in the UnitedStates and the distributions of the population with respect to physical, physiological, and psycho-

logical characteristics; and (2) analysis of relationships among the various measurements withoutreference to an explicit finite universe of persons.

Data j%om the Institutional Popu.la tion 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 porn the Hospital Dischavge SuYvey. —Statistics relating to discharged patients in short-stayhospitals, based on a sample of patient records in a national sample of hospitals.

Data on health TesouYces: manpower and facilities. —Statistics on the numbers, geographic distri-

bution, and characteristics of health resources including physicians, dentists, nurses, other health

occupations, hospitals, nursing homes, and outpatient facilities.

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

geographic and time series analyses.

Data on natality, mawiage, and divorce. —Various statistics on natality, marriage, and divorce

other than as included in regular annual or monthly reports+pecial analyses by demographicvariables, also geographic and time series analyses, studies of fertility.

~ta from the National Natality and Mortality Surveys. — Statistics on characteristics of births

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

recorcts, including such topics as mortality by socioeconomic class, hospital experience in thelast year of lift, 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, HRARockville, Md. 20852

Characteristics of Personswith Corrective Lensespopulation aged 3 and over had corrective lenses,...

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