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ABSTRACT
AN OTOLARYNGOLOGICAL AND AUDIOLOGICAL EVALUATION

OF CHICANO MIGRANT AGRICULTURAL WORKERS
IN MICHIGAN

BY

Beverly Ann Hern Goldstein

Sixty Chicano migrant agricultural workers, 37 children
and 23 adults, served as subjects to determine: (1) if
there is a higher incidence of middle ear pathology among
Chicano migrant workers than in the general population;

(2) if there is a higher incidence of hearing loss; (3) if
the incidence of middle ear prdblems decreases as a function
of age in the Chicano population; and, (4) how the air—
conduction hearing threshold levels of the children and
adults in this population compare with threshold data from
aprevious studies on children (Eagles et al., 1963 and the
United States Health Education Welfare study, 1970) and
adults (Corso, 1963).

All tests were administered in a mobile hearing test—
ing trailer in two different migrant housing camps. All
sixty subjects initially responded orally to a question-
naire; parents responded for the younger children. The
subjects then received an ear, nose, and throat (ENT) exami-
nation by an otolaryngologist, and finally an air- and bone-

conduction hearing threshold test by an audiologist°

usi

acc

8‘: E

Beverly Ann Hern Goldstein

The interviews were recorded both on tape and also in
written form° The interviewers (two) were bilingual, cap-
able of communicating in English and in Spanish.

The audiometric testing was conducted in a one room
test suite housed in the testing trailer. Pure-tone air—
and bone-conduction thresholds were measured in 5 dB steps
using the Hughson—Westlake ascending technique. Masking,
according to the Studebaker technique, was employed when—
ever an air-bone gap equal to or greater than 10 dB was
noted.

A high incidence of middle ear pathology was noted
for both children (60%) and adults (80%). This incidence
is much greater than that found by Eagles et a1. (1963),
Cambon, Galbraith, and Kong (1965), Ling, McCoy, and Levinson
(1969), and Fay et a1. (1970). For children the incidence
of pathology manifested itself audiologically in the form
of air—bone gaps, while for adults clinically insignificant
air-bone gaps were noted. Middle ear problems did not
decrease as a function of age. 1

This investigation demonstrated that although mean and
median air-conduction hearing threshold levels were within
normal ISO (1964) limits bilaterally, thresholds for Chicano
children were poorer at most frequencies than thresholds
obtained by Eagles et al. (1963) and the United States
Health, Education, and Welfare (1970) study. Hearing thres-

holds for Chicano adults became poorer as a function of age,

Beverly Ann Hern Goldstein

as expected, but the adults in this study also demonstrated
poorer thresholds than those found by Corso (1963).
Generally, the Chicanos in this study had essentially
borderline normal hearing for their age groups.

The results of this investigation may not be applica-
ble to all Chicano migrant workers nor to the total United
States migrant population. However, the data does suggest
that there is a need for improved otolaryngological and
audiological services for migrants living in Michigan.

A full-scale investigation, possibly coordinated by the
United States Public Health Service, appears necessary in
order to determine the general incidence of middle ear
problems among migrant agricultural workers in the United

States.

6 // '2 ’2 9’51

AN OTOLARYNGOLOGICAL AND AUDIOLOGICAL EVALUATION
OF CHICANO MIGRANT AGRICULTURAL WORKERS

IN MICHIGAN

BY

Beverly Ann Hern Goldstein

A THESIS

S ubmi tted to
Michigan State University
in partial fulfillment of the requirements
for the degree of

MASTER OF ARTS

Department of Audiology and Speech Sciences

1972

and S
State

for t

Accepted by the faculty of the Department of Audiology
and Speech Sciences, College of Communication Arts, Michigan
State University, in partial fulfillment of the requirements

for the degree of Master of Arts.

Thesis Committee : ”my 'M Director

William F. Rintelmann, Ph. D°

9L? KQW

L‘RTKapurQM.‘ D.

L, 21% 22%. N
‘fggnie . Beasley, Ph. D;

W257;

Oscar I. Tosi, PH. 5. '

 

 

 

ii

Wht

ACKNOWLEDGMENTS

I wish to express my appreciation to Dr. William F.
Rintelmann for his guidance and support as my thesis advisor,
and also to Drs. Y. P. Kapur, Daniel S. Beasley, and Oscar
I. Tosi, the members of my committee, for their valuable
assistance in the preparation of this thesis.

I further wish to thank Y. P. Kapur, M. D., Department
of Audiology and Speech Sciences, Michigan State University,
who devoted several hours to examining a large percentage of
the subjects for the present investigation.

I would also like to express appreciation to both Denis
Ortiz and George Fuller of the Michigan Association for
Better Hearing and Speech for providing the testing trailer
and audiometer. Special thanks goes to George who trans-
ported the equipment to the two migrant housing camps.

I also wish to thank Donald Riggs, Department of Audiology
and Speech Sciences, Michigan State University, for his
technical assistance with the instrumentation.

Special appreciation goes to Joe Flores, United Migrants
for Opportunity, Inc., Saginaw, Michigan, for providing
information on the location of testing areas in two Chicano
migrant camps in central Michigan. I further appreciate the
interviews taken down in writing and tape-recorded by Sandra
Alvarez and Helen Parker and the time given by the sixty
people who so willingly served as subjects.

I am appreciative to Dr. Beasley, my academic advisor
and to Dr. Tosi for their continued advice and support
throughout the academic year.

Most of all, I want to thank Michael, my patient husband,
for his continuous assistance, suggestions, and support
throughout this investigation and graduate school.

 

iii

CHI-i

II

TABLE OF CONTENTS

CHAPTER Page
LIST OF TABLES o o o o e o o e o o o o o e o 0 Vi

LIST OF FIGURES O O O O O O C O O O O O O O 0 ix

I. INTRODUCTION, REVIEW OF THE LITERATURE, AND

STATEMENT OF PURPOSE . . . . . . . . . . . 1
Introduction . . . . . . . . . . . . . . . 1
Review of the Literature . . . . . . . . . 2
Normal Incidence of Hearing Loss for
Children and Adults. . . . . . . . 2
Incidence of Middle Ear Pathology in
Socio-economically Depressed Popula-
tions. ... . . . . . . . . . . . . . 6
General Living Conditions of Chicano
Migrant Agricultural Workers . . . . 11
Statement of Purpose . . . . . . . . . . . 21
II. EXPERIMENTAL PROCEDURES . . . . . . . . . . . 23
Subjects . . . . . . . . . . . . . . . . . 23
Equipment. . . . . . . . . . . . . . . . . 23
Tests and Procedures of Administration . . 26
Otolaryngological Examination. . . . . . . 26
Interview. . . . . . . . . . . . . . . . . 27
Forms. . . . . . . . . . . . . . . . . . . 27
III. RESULTS AND DISCUSSION. . . . . . . . . . . . 28
Interview. . . . . . . . . . . . . . . . 28
Otolaryngological Examination. . . . . . . 32
AudiOIOgical Evaluation. . . . . . . . . . 37
Children. . . . . . . . . . . . . . . . 37
Adults. . . . . . . . . . . . . . . . . 58
Referrals. . . . . . . . . . . . . . . . . 73
Discussion . . . . . . . . . . . . . . . . 74

iv

“1

TL

’99

TABLE OF CONTENTS--Continued

CHAPTER Page
IV. SUMMARY, CONCLUSIONS, AND RECOMMENDATIONS FOR

FUTURE RESEARCH. O 0 O 0 0 O O O O O O O O 7 9

smary O O O O O O O O O O O O O O O 0 O O 7 9

Conclusions. . . . . . . . . . . . . . . . 80

Recommendations fo Future Research. . . . 82

LIST OF REFERENCES 0 O O O O O 9 O O O O O O O O O O 84

APPENDICES 9 O O O O O O 0 C 0 C O O C 0 O O O O O O 89

A. AMBIENT NOISE LEVELS IN TEST ROOM . . . . . . 90

B. PACKET OF FORMS USED TO RECORD TOTAL DATA FOR
EACH SUBJECT O O C O O O O O O O O C O O O 92

C. COMPARATIVE DATA OF AUDIOMETRIC NORMS AND
EARPHONES 0 O O O O O O O O O O I C C O O 0 99

D. CORSO (1963) MEAN AIR-CONDUCTION THRESHOLDS
IN SOUND PRESSURE LEVEL. . . . . . . . . . 102

E. RAW DATA OF AIR-CONDUCTION THRESHOLDS FOR
CHILDREN AND ADULTS O O O O O O C O O C O C 104

F. RAW DATA OF AIR—BONE GAPS FOR CHILDREN AND
ADULTS O O O O O C O O O O O O O O O O O O 1 10

 

10

LIST OF TABLES

TABLE

10.

Answers to questions posed to the parents of
the children tested. . . . . . . . . . . . . . .

Answers to questions posed to adult subjects . .

Number and percentage of otolaryngological find-
ings for 25 children ages 5-16 years for both
unilateral and bilateral pathology . . . . . . .

Number and percentage of otolaryngological find-
ings for 15 adults ages 18-40 years for both
unilateral and bilateral pathology . . . . . . .

Age distribution of children audiometrically
tested 0 0 O O O O O O O O O I O O O O O O O O 0

Mean, median, range, and standard deviation of
air-conduction thresholds in dB re: ISO (1964)
and air-bone gap data for all children ages 5-16
years classified by frequency and ear tested . .

Median air-conduction hearing threshold levels
in dB re: 0.0002 microbar using values for the
Western Electric 705 A earphone for the migrant
children tested and for the children tested by
Eagles et a1. (1963) and the United States
Department of Health Education and Welfare .
(1970), classified by frequency and ear tested‘.

Age distribution of adults audiometrically
tested 0 O O O O O O 0 O O O C O O O 0 O O O 0 0

Mean, median, range, and standard deviation of
air-conduction thresholds in dB re: ISO (1964)
and air-bone gap data for adults ages 18-24
years classified by frequency and ear tested . .

Mean, median, range, and standard deviation of
air-conduction thresholds in dB reg ISO (1964)
and air—bone gap data for adults ages 25—32
years classified by frequency and ear tested . .

vi

Page

29
30

33

34

38

39

54

59

6O

61

12.

A1.

C1.

C2.

D1.

El.

32.

E3.

E4.

LIST OF TABLES--Continued

TABLE Page

11.

12.

A 1.

Mean, median, range, and standard deviation of
air-conduction thresholds in dB re: ISO (1964)

and air-bone gap data for adults ages 33-40

years classified by frequency and ear tested . . 62

Mean, median, range, and standard deviation of
air-conduction thresholds in dB re: ISO (1964)

and air-bone gap data for adults ages 43-50

years classified by frequency and ear tested . . 63

Acoustical survey of the noise levels in the
test room used for audiometric testing . . . . . 91

Sound pressure values in decibels re: 0.0002

microbar for each frequency classified by norms

and type of earphone according to data pre-

sented by Davis and Krantz (1964) and Cox and

Bilger (1960). . . . . . . . . . . . . . . . . . 100

The sound pressure level difference in decibels

for each frequency between the Western Electric

705 A earphone and the Telephonics TDH 39 ear-

phone housed in the MX 4l/AR cushion (Cox and

Bilger, 1960). . . . . . . . . . . . . . . . . . 101

Mean air-conduction hearing threshold levels in

dB re: 0.0002 microbar for right and left ears

and male and female combined for adults ages

18-49 years of age, Corso (1963) . . . . . . . . 103

Air-conduction threshold levels in dB for the
right ear for all children ages 5-16 years re:
ISO (1964) o o o o o e o o o o o o e o o o o o o 106

Air-conduction threshold levels in dB for the
left ear for all children ages 5-16 years re:
ISO (1964) 0 O O O O O O O O O O O 0 O O O O O O 107

Air-conduction threshold levels in dB for the
right ear for all adults ages 18-50 years re:
ISO (1964) O O O O O O O O O O O O O O O O O O O 108

Air-conduction threshold levels in dB for the

left ear for all adults ages 18-50 years re:
ISO (1964) O O I O O O O O O O O O O C O O O O O 109

vii

LIST OF TABLES—-Continued

TABLE Page
F 1. Air—bone gaps in dB for each frequency for the

right ear on all children ages 5-16 years . . . 112
F 2. Air-bone gaps in dB for each frequency for the

left ear on all children ages 5-16 years. . . . 113
F 3. Air-bone gaps in dB for each frequency for the

right ear for all adults ages 18-50 years . . . 114
F'4. Air-bone gaps in dB for each frequency for the

left ear for all adults ages 18-50 years. . . . 115

viii

LIST OF FIGURES

FIGURE

1.

Mean air-conduction hearing threshold levels

in dB re: ISO (1964) for all children ages

5-16 years, including one standard deviation,

by frequency and ear tested. . . . . . . . . . .

Percentage distribution of children 5—16 years,
by hearing threshold levels in dB re: ISO
(1964) for the right ear at each test frequency.

Percentage distribution of children 5-16 years ,
by hearing threshold levels in dB re: ISO (1964)
for the left ear at each test frequency. . . . .

Percentage distribution of children 5-16 years,
by hearing threshold levels in dB re: ISO (1964)
for combined ears at each test frequency . . . .

Mean hearing threshold levels in dB re: ISO
(1964) by air— and bone-conduction for all
children ages 5-16 years by frequency and ear
tested. Shaded area is the air—bone gap . . . .

Mean air—conduction hearing threshold levels in
dB re: ISO (1964) for the 25 children who
received the otolaryngological examination,
separated by ear into two groups: otolaryngo-
logically normal and abnormal. . . . . . . . . .

Median air-conduction hearing threshold levels
in dB re: ISO (1964) for the right ear from the
present study, the Eagles et a1. (1963) and the
U. S. Dept. of Health (1970) studies. Values
are computed for the Western Electric 705 A ear-
phone. . . . . . . . . . . . . . . . . . . . . .

Median air-conduction hearing threshold levels
in dB re: ISO (1964) for the left ear from the
present study, the Eagles et a1. (1963) and the
U. S. Dept. of Health (1970) studies. Values
are computed for the Western Electric 705 A ear-
phone. . . . . . . . . . . . . . . . . . . . . .

Page

40

43

45

47

49

51

55

56

1C

11

12.

31.
32.

LIST OF FIGURES--Continued

FIGURE Page

9.

10.

11.

12.

B 1.

B 2.

Mean air-conduction hearing threshold levels

and range (shaded area) in dB re: ISO (1964)

for the right ear at all frequencies for all

adults ages 18-50 years separated into age

groups. . . . . . . . . . . . . . . . . . . . . 64

Mean air—conduction hearing threshold levels

and range (shaded area) in dB re: ISO (1964)

for the left ear at all frequencies for all

adults ages 18-50 years separated into age

groups. . . . . . . . . . . . . . . . . . . . . 65

Mean thresholds in dB re: ISO (1964) by air—

and bone-conduction for all adults ages 18—50

years by frequency and ear tested. Shaded area

is the air-bone gap . . . . . . . . . . . . . . 68

Mean hearing threshold levels in dB re: ISO
(1964) for left and right ears and male and
female combined from the present study and the
Corso (1963) study, computed for the TDH 39

earphone housed in the MX 4l/AR cushion . . . . 71
Physical Examination. . . . . . . . . . . . . . 95
Audiogram . . . . . . . . . . . . . . . . . . . 98

 

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CHAPTER I

INTRODUCTION, REVIEW OF THE LITERATURE,
AND STATEMENT OF PURPOSE

Introduction

Several studies have been reported in the literature
concerning the incidence of middle ear problems in various
socio-economically depressed communities. High percentages
of middle ear abnormalities and conductive hearing losses
have been found in the following six populations:

(1) Canadian Indians (American Indians native to Canada)
living on the Mount Currie Reservation in British Columbia
(Cambon, Galbraith, and Kong, 1965); (2) School children of
India, ages 5—15 years (Kapur, 1965); (3) American Indian
children in South Dakota (Clifford, Hull, and Gregg, 1966);
(4) School children in Vancouver, British Columbia (Robinson,
Anderson, and Moghadam, 1967); (5) The entire Eskimo p0pula-
tion of Cape Dorset, Baffin Island (Ling, McCoy, and Levinson,
1969); and (6) An inner-city population of children residing
in the New York City Department of Social Services Children's
Center (Fay et al., 1970). Most of the above investigators
concluded that the socio-economic environment of a community

can influence the incidence of middle ear problems.

 

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At present, there is a subculture of Chicano migrant
agricultural workers (persons of Mexican extraction who
live in and are citizens of the United States and who
migrate throughout the United States harvesting crops) for
Which no published data presently exists relative to
incidence of middle ear prOblems. The Chicano migrant
workers live and travel with their children under adverse
conditions. The possibility exists that they also exhibit
a high incidence of middle ear pathology. The interest in
this study was to investigate middle ear prdblems of both
Chicano adults and children traveling in the migrant agri-
cultural stream through the central region of Michigan dur-

ing August, 1971.

Review of the Litgiatugg

Ngimal Incidence of Hearing Loss for
ghiigren and Adults

Before it is possible to determine whether Chicano
children and adults in the migrant stream.have an incidence
of hearing loss and/or middle ear disease that is higher than
,in the general population, it is necessary to become familiar
with what has been found to be "normal" incidence of hearing
loss. _Farrant (1960, p. 23) in Australia, suggested that
the "incidence of measurable hearing defects can be expected
on the order of about 5x.of ears or 3%.of children audio-

metrically screened, incidence varying considerably with

popu,
aid 1

expls
medi:

C017.)

population characteristics such as socio-economic status

and probably with seasons." He felt that once these children
have been detected, it is necessary to communicate and
explain the audiometric data to parents, teachers, and
medical practitioners, and ultimately develop an informed
community.

Eagles et al. (1963) reported the results of an extensive
study involving 4078 children conducted in Pittsburgh,
Pennsylvania between June, 1958 and August, 1960. The
children ranged in age from five to fourteen years and ade—
quately represented age and sex distribution and socio-
economic characteristics of school—age children in Pittsburgh.
These investigators found that 2891 children (70.9%) had ears
which were otoscopically normal, while 622 children (15.2%)
had otoscopically abnormal ears. Due to impacted cerumen,

565 children (13.9%) had inconclusive otoscopic examinations.
The abnormalities found included tympanic membrane perfora-
tion with and without discharge, impaired mobility with dis-
coloration and retraction of Pars Tensa, retraction of Pars
Tensa as a single sign and with other signs, retraction of

Pars Flaccida, bulging, impaired mobility, increased vasculari—
zation, scars, and calcium plaques. In the group with abnor-
malities (15.2%), Eagles et al. reported 3%.to have active
middle ear disease and 12% to have evidence of past disease.

Approximately 75% of all the children tested by Eagles

et al. had thresholds more sensitive than audiometric 0 re:

ASA (1951). Girls were found to have more sensitive hearing
than boys except at the frequency 250 Hz. The differences,
however, were not large; the greatest being 2 dB at 6000 Hz.
The differences between white and non-white children with
respect to threshold were found to be on the order of 1—2 dB
with no consistent trend. During the winter months there
were two periods when the children tended to show a loss in
threshold sensitivity. These phases coincided with epidemics
of acute respiratory infection. Most categories of abnormal
ears had significantly less sensitive hearing levels when com-
pared with those children with normal ears, but this was not
true in all cases. Eagles et a1. suggested that case—finding
should take place early, hOpefully in the pre—school years.

The United States Department of Health Education and
Welfare (1970) reported on an even more comprehensive study
of hearing threshold levels of children conducted from July,
1963 to December, 1965. The national sample of 7119 children
examined were "representative of the roughly 24 million non—
institutionalized children 6-11 years of age in the United
States with respect to age, sex, race, region, size of place
of residence, and change in size of place of residence from
1950-1960." (p. 1) It was found that for the better ear,
more than 70% of the children had hearing thresholds better
than 0 dB Hearing Level (HL) re: ASA (1951). Thresholds
were somewhat poorer at 3000, 4000, 6000, and 8000 Hz than
for the lower test frequencies. Most children were found

to have similar hearing thresholds in both ears; little

difference was noted between boys' and girls' threshold
levels. At the frequencies 250—2000 Hz, hearing sensitivity
of children appeared to increase with advancing age. The
estimated prevalence of hearing loss in this survey was found
to be quite low. The percentage of pure—tone averages (500,
1000, and 2000 Hz) of 15 dB or greater re: ASA (1951) was
judged to be slightly less than 1% of the children tested.
The number of children in this age group in the United States
with hearing handicaps was then estimated to be 213,000.
Although audiometric zero re: ISO (1964) has been
generally accepted as the adult norm for hearing threshold
levels, this norm was based on the hearing ability of indi-
viduals 18—24 years of age. Corso (1963) found that hearing
acuity for adults decreases with advancing age. He recom—
mended that the reference for normal hearing during a person's
twenties should not be used as the criteria to determine
normal hearing of persons in their thirties and older. Corso
found the hearing of women to be on the average more acute
than that of men. The differences between sexes were most
marked at the higher frequencies with the crossover point in
the region of 1000 Hz. Both men and women had hearing loses
which progressively spread from the higher to the lower fre-
quencies. Men were affected earlier, beginning on the average
at age 32 years; presbycusis for women proceeded at a faster

rate although it did not begin until age 37.

nn_ 3 .1
7!. Co ....—

Inc1dence of Middle Ear Pathology in
Soc1o-economically Depressed Popula-
tions

 

Investigators have recently examined the hearing levels
and incidence of middle ear disease of three socio-
economically depressed populations in North America. Cambon,
Galbraith, and Kong (1965) tested Indians on the Mount Currie
Reservation in Vancouver, British Columbia. Of the 504 per—
Sons tested, 79 (15.7%) had active middle ear pathology, and
226 (44.8%) had signs of previous disease. Twenty-one (4.2%)
had active bilateral middle ear disease. Formal testing was
done on 364 persons, 112 (37.9%) of whom showed losses greater
than 15 dB re: ASA (1951) for the speech frequencies. The
authors felt that poor housing conditions, poor housekeeping,
low income, poor family functioning and the presence of nasal
discharge were influencial in the high incidence of hearing
loss. The investigators reported: "Among those living under
the most desperate social situations, active ear disease was
present in more than one in three." (p. 1304) Middle ear
disease was found to begin early in life and recur freqhently.
Cambon, Galbraith, and Kong concluded that "the incidence of
ear disease is significantly higher where social conditions
are poor." (p. 3105)

Ling, McCoy, and Levinson (1969) studied the Eskimo popu-
lation in Cape Dorset, Baffin Island. Active ear pathology
revealed by otosc0pic examination was found to be present in
30.8% of the 525 individuals ages birth to 79 years. They

did not find any significant decrease in the incidence of

active ear disease with increasing age. Chronic rhinitis
characterized by massive mucoid or mucopurelent nasal and
post-nasal discharge was commonly found and frequently
associated with hypertrophy and/or infection of the adenoid
tissue. (p. 385) Also seen was a high proportion of middle
ear discharge. The standards of hygiene were found to be
poor: homes were not clean; children frequently went un-
washed; food was prepared, served, and eaten with dirty
hands: children had inadequate clothing for the weather;
and diets were basically ill-balanced. These factors were
seen as substantially contributing to the incidence of
middle ear disease. Ling, McCoy, and Levinson suggested
that early identification of conductive deafness in pre-
school children could best be carried out by otoscopic
examination. They further recommended intensive education
programs for the Eskimo population in the areas of hygiene
and diet.

Live-voice speech stimuli were used by Ling, McCoy,
and Levinson (1969) for testing hearing acuity because their
audiometer needed recalibration. Significant hearing impair-
ment, using live-voice whisper testing, was found to occur
very rarely in children 5-17 years old as compared with the
high incidence of middle ear disease. A child who could
repeat English syllables whispered at a distance of 15 feet
'was considered to have normal hearing. Nine children
demonstrated hearing loss; three required and obtained hear—

ing aids. It is unfortunate that these investigators were

not able to obtain pure-tone threshold data. The employ-
ment of live-voice whisper testing is an inapprOpriate
method for detecting hearing loss. Empirical evidence

has demonstrated that persons with normal hearing in the
low frequencies and a loss in the high frequencies will not
be detected with this method. According to Newby (1964,

p. 59) this technique is only "useful in detecting gross
deviations from normal hearing."

Fay et a1. (1970) conducted a hearing screening in-
vestigation of a sample of inner city children in New York.
A total of 461 children, ranging in age from 2—16 years,
residing at that time in the New York City Department of
Social Services Children's Center, were tested; 19.8%
failed the final screening. The investigators suggested
that this is an accurate estimate of the incidence of hear-
ing impairment in this population. Fay et a1. suggested
that this incidence exceeds that found by Farrant (1960),
Melnick et a1. (1964), and Robinson et a1. (1967). Otoscopic
examinations were also performed by Fay et al. on 225
children: 46% were found to have positive ear, nose, and
throat pathology while only 24% were found to be otoscopical-
ly abnormal. Many were found to have multiple pathological
conditions of the ear. The investigators did not find a
decrease in ear pathology as a function of increased age.
0f the 225 children, only 175 had received the hearing
screening test. In reviewing the literature, Fay et al.

discussed the Clifford et al. (1966) study conducted in

South Dakota on a population of Indian children. In this
investigation the final incidence of threshold failures of
the Indian pOpulation was 27.2%. Fay et a1. concluded that
all of these studies, when reviewed as one problem, indicate
relatively high incidence of middle ear problems among
disadvantaged children from both rural and urban popula-
tions. They indicated that these findings might be accounted
for on the basis of inadequate medical attention and that an
urgent need existed for increased otological and audiological
services to individuals from low socio-economic areas through-
out the United States and Canada.

A review of the literature points out that children
with otologic abnormalities are not always detected by hear-
ing screening examinations and that hearing impairments can-
not be readily diagnosed solely through otologic examinations.
Jordan and Eagles (1961) found data which indicated that
audiometric testing, however complete, cannot identify all
physical abnormalities of the ear which warrant medical
treatment. Eagles et al. (1963, p. 142) further stated that
"despite the less sensitive average hearing levels in children
with otoscopic evidence of disease, many of them have hearing
as sensitive as children without such evidence." They men-
tioned that audiometric testing may show normal hearing,
even though the child may have abnormalities of the ear.

Melnick, Eagles, and Levine (1964) were also in favor
of both otolOgical and audiological evaluation in diagnosing

prdblems of the middle ear. They found that threshold tests

10

did not identify children with active otoscopic evidence.
Following these investigations, Kapur (1965) did an extensive
study of 857 children representing various socio-economic
backgrounds in India. He found a high incidence of conduc-
tive hearing loss and also found that between 7.3% and 9.2%
of the children with normal hearing had otologic abnormali—
ties. Kapur suggested that ”in a hearing—survey program,
audiometry should be accompanied by an ear, nose and throat
examination to uncover otologic abnormalities which do not
show a hearing loss." (p. 321) Fay et a1. (1970, p. 369)
believed that their data supported the notion that "neither
hearing screening nor otological examination is sufficient
alone to identify both hearing impairment and ear pathology."

Various investigators have studied the amount of loss
which usually accompanies middle ear disease. Jordan and
Eagles (1961) found the mean hearing levels for 82 ears
which showed a combination of signs suggesting secretory
otitis media to range from —21 to +39 dB HL re: ASA (1951).
Kapur (1964) found that children who have middle ear effu-
sions may have a hearing loss in the range of 10-40 dB HL
re: British Audiometric Zero.

Various investigators have concerned themselves with
climatic variability. Farrant (1960) found a greater in-
cidence of hearing loss during the winter months, and Eagles
et a1. (1963) also noted decreased hearing sensitivity in
winter. Anderson (1965) looked at the difference in incidence

of conductive hearing loss between persons living in several

11

arid counties and coastal counties in Oregon. The findings
indicate that a higher incidence of conductive hearing loss
is found in the coastal counties; this has been linked to
the climatic conditions, rainfall, and humidity.

To date, there has not been any indication in the
literature that would lead to an expectation of poorer audi-
tory acuity for the Chicano population. Eagles et al. (1963)
did not find significant differences in the hearing acuity
of white and non-white children. It is not known if Chicanos
were represented in their sample population. Shepherd, Gold-
stein, and Rosenblfit (1964) tested adults to determine if
differences in auditory sensitivity existed between white and
black populations of the same socio-economic background. No
differences were noted between males; white females showed
minimally better thresholds than black females.

General Living Conditions of Chicano
Migrant Agricultural Workers

In order to assist the reader in understanding the
author's interest in investigating the incidence of middle
ear problems among Chicano migrant agricultural workers, it
is necessary to describe the migrant's present social and
economic position in the United States.

Most migrant farm workers are individuals who move
regularly or irregularly following the crop harvests, living
every year in various areas of one or more states often with
varying climates. According to the Michigan Governor's Task

Force on Migrant Labor (1969), the problems migrants face

are also tied to various other aspects of rural poverty.
Minority groups that are most often affected by the problems
inherent in rural poverty are the American Indians, the
Blacks, the Puerto Ricans, the Chicanos, and white indi—
viduals from various regions of Appalachia.

There are approximately 400,000 to 450,000 migrants
traveling in three main streams throughout the country.
The Pacific Coast stream begins the agricultural picking
season in Texas, moves on to southern California, and works
up through Oregon and into Washington. It then turns back
and heads south. The middle migrant stream begins in the
central regions of Texas and works up through Oklahoma
north to Minnesota, Wisconsin, Ohio, and Michigan. Along
the Atlantic Coast can be found the third stream. Consisting
mostly of Black families, it begins in Florida about mid-
May or June, and passes through Georgia, the Carolinas,
Virginia, Delaware, New Jersey, New York, and into the New
England states. These workers remain for the summer and
early fall, and then work their way south back to Florida.
According to Koch (1966, p. 172), Director of the Migrant
Citizenship Education Project, "the large majority of those
who work seasonally in the crops would remain stable if the
economy permitted them to do so." As many as 60% of the
Chicanos from south Texas who were formerly in commercial
crews now travel independently in extended family groups.
The main concerns of those traveling in the streams are

survival and security.

13

The Field Study of Migrant Workers in Michigan (1969)
sampled 41 families for a total of 334 people. The ex—
tended family was found to be common in the migrant stream.
Extended family groups are defined as father, mother,
siblings, grandparents, married sons and their wives and
children, aunts, uncles, and cousins living together as a
family unit. They found that "the migratory work force was
composed basically of very young and older people in large
family groupings." (p. 9) Most migrant farm workers were
not the tough younger workers so often visualized, but
rather those still too young to become independent and
seek improved job opportunities or those too old to leave
the stream, inhibited by their inability to speak English
and by poor health and a lack of other work skills. Migrant
streams lacked workers between the age range 20-35 years.
This Field Study found that the number of persons in a
family ranged from 1-17 people with a mean size of 8.1
persons. Sixty-three percent of all workers were under 20
years of age and of these, 53% were 18 years and younger.
Thirty percent of the total workers were 35 years and older.

Sandage (1968), working as the Executive Director of
Migrant Action programs in Iowa and southern Minnesota,
showed that in 1966 the migrants who worked in Texas worked
in 36 other states in the same calendar year, and that
Michigan and Ohio were the largest users of these individuals.
She also found that the industries which rely heavily on the

work of the migrants are: fruit and nut orchards, cotton,

14

tobacco, and vegetable fields. Migrants have been found
by the Report and Recommendations on the Status of Migra-
tory Farm Labor in Michigan (1968) to have severe problems
such as: (1) poor health due t0poor or nonexistent
medical facilities; (2) improper nutrition; (3) substandard
wages in relation to the wages of various other unskilled
laborers; (4) poor housing conditions at most migrant camp
sites; (5) inelegibility for most federal assistance pro-
grams due to their mobility and lack of state residency:
and (6) low average levels of education. These six problem
areas are described in greater detail below.

Child labor is prevalent, according to Sandage (1968),
and it has been excused as necessary in the migrant culture
by migrants themselves and by many other individuals who
have refused to see the problem as it exists today. Bowles
(1967), the Supervisory Statistician for Economic Research
for the United States Department‘of Agriculture, has sug-
gested that it is the heavy proportion of children living
and working within the migrant streams that has created such
a great concern over the welfare of the total population.
At an early age migrant children have been expected to con-
tribute to the family income by working in the fields along
with the other members of the family. Agricultural work is
an extremely hazardous job from the vieWpoint of accidents
for all workers, and it becomes even more dangerous for
young children. Child labor has also been excused in the

past and somewhat in present times, for it has helped to

15

minimize farm production costs. Many of the children in the
migrant stream grow up to become adult workers, and eventual—
ly migrant parents. These children who remain in the stream
are no further ahead economically, socially, educationally,
or culturally than were their parents.

Public aid has not always been available to the migrant
workers due to residence requirements. so migrants have
generally been ineligible for treatment at public hospitalsamd
for general medical care. Many have not been made aware of
the health services for which they are eligible. A United
States Public Health Survey conducted in 1967 found that the
death rate of migrants as a sub-group was much higher than
the national average. Broken down into categories (Sandage,
1967, p. 13), infant and maternal mortality were both 125%
higher than the national average, influenza and pneumonia were
200% higher than the national average, and tuberculosis and
other infectious diseases were 260% higher than the national
average. More specifically (Journal of American Medical
Association, 1971, p. 521), tuberculosis has been found to
occur in the general United States population in 21.3 persons
per 100,000. Epidemics are frequent, and they are difficult
to control due to the high mobility of the workers.

Preventative medical measures have seldom been taken
such as immunization, chest X—rays, and regular check-ups.
Quite recently in Michigan, a program to arrest infectious
diseases in the migrant population using antibiotics was

initiated. A description of the program is available in

16

the Migrant Health Program Annual Progress Report (1970).
Of the 2881 total visits to the combined clinics of the East
Central Michigan Health Service, 791 (27%) were to treat
diseases of the respiratory system. Thus, over one quarter
of the visits were to treat physical problems which could
contribute to conductive hearing loss. Indian Health Trends
and Services found otitis media to be the most common notifi—
able disease among North American Indians, occurring in
9,115.2 per 100,000 (Journal of American Medical Associ-
ation, 1971, p. 521). Ear pathology appeares to be extremely
common among both of these groups. There were 338 visits to
the East Central Michigan Health Service by Chicanos for
symptoms and ill-defined conditions, 297 visits for cure of
diseases of the skin and subcutaneous tissue, 240 visits due
to diseases of the nervous system and sense organs, 198
visits due to diseases of the digestive system, 167 visits
necessary because of accidents, poisonings, and violence, and
161 visits to treat endocrine, nutritional and metabolic
diseases. (p. 3—5) Other migrants who also required these
various health services were not treated if they were not in
an area with a clinic, not aware of the available service, or
not able to reach the clinic due to lack of transportation.
Allen (19669,"Ruel (I967), and Sandage (1968), although not citing
any statistical data, have written lengthy narratives on
the nutritional trends of migrant workers. Because migrants
have low incomes and the money cannot all be spent on food,

migrant workers spend much less on groceries per week than

17

the average American family of equal size. Dairy products
are consumed in less quantity, for most families have no
refrigeration facilities. Children are generally breast—fed
until 18-24 months of age, but following this period of
time, consume less milk than other children their age.
Since the cost of meat is higher than other food products,
there is a trend among migrant workers of eating more
starches and less meat. Generally, they do not buy fruits
and vegetables, although they do eat these products while
working in the fields. Ling, McCoy, and Levinson (1969)
have suggested that ill-balanced diets (such as those
described above) substantially contribute to incidence of
middle ear disease.

Migrant workers have been employed annually in 55
counties in Michigan. According to the Field Study of
Migrant Workers in Michigan (1969, p. 10) "the migrant
worker in Michigan has not been getting the legal minimum
wage, he has gotten no unemployment benefits, he has been
excluded from workmen's compensation and deprived of social
security benefits." The rate of payment for migrant labor
has usually been contracted by the acre, pound, or bushel.
Thus, pickers must harvest rapidly, since their wages are
directly dependent upon how much they are able to harvest
in a day. The Field Study of Migrant Workers in Michigan
(1969, p. 9) further reported that ". . . workers paid by
piece-rate consistently failed to earn an amount equal to

the minimum hourly wage of $1.25."

18

Many migrant camps are in poor condition with no indoor
or outdoor plumbing, sometimes no electricity, clean water,
shower facilities, or heat, and occasionally no windows or
doors on the cabins. The lack of trash cans or other methods
of eliminating trash cause a heavy concentration of flies
and rodents. The homes are usually no larger than two rooms
with one bed for every three or four persons. A few good
migrant camps do exist, but according to the Report and
Recommendations on the Status of Migratory Farm Labor in
Michigan (1968), they are rare. Various explanations have
been given by growers as reasons for not improving migrant
housing: "'(1) Mechanical harvesters will replace workers
in the near future: (2) Housing facilities are used only a
few weeks out of the year; (3) Although the housing leaves
something to be desired, it is at least equivalent to what
workers have in their home~base areas; (4) All too often
there has been willful destruction of very fine facilities
that were provided.'" (p. 10)

According to Servin (1970), Chicanos have the poorest
socio-economic record of all minority groups recorded in the
1960 United States Census. Outside of New Mexico, they are
grossly under-represented and ignored in political appoint—
ments. The most significant offices held by Chicanos are
in the Department of Education. Migrants have been specifi—
cally excluded from all major federal labor legislation,
and due to a lack of residency, they are not eligible for

much of the early 1960's poverty legislation.

19

The Michigan Civil Rights Commission in its Report and
Recommendations (1968) concluded that there are three
general ways by which the migrant population is systematical—
ly excluded from Civil and legal rights, Opportunities, and
privileges. These are: (1) Inadequate protective legisla-
tion and enforcement of legislation: (2) Inadequate staff,
information and outreach; they are left without information
regarding rights and services of which they could take
advantage; (3) Uncoordinated efforts; the amount of activity
and responsiveness that does exist, although well-intentioned,
remains uncoordinated. Therefore, non-cooperation exists,
as does duplication, wasted effort in minor areas of need,
and no effort in some major areas of need.

The average adult migrant has had the equivalent of a
third grade education. Some of the older migrants actually
have no formal education. According to Bowles (1967) it is
the low education of the majority of the parents and the
intermittent and seasonal nature of the farm.work which
produce conditions that help to perpetuate low educational
aspirations from one generation to another.

The migrant child is strongly attached to his family,
and he perceives school experiences and social relationships
as having a secondary importance. Migrant children move
frequently from school to school as they travel and are
generally not in one school long enough to accept it as an
integral part of their lives. Most schools have not adjusted

to the situations which migrants face daily. The typical

school program has not, in most cases, successfully inte—
grated the strong social needs of the migrant child with his
educational needs. The migrant child is not usually in the
same grade as the other children his age. Chicano children
are usually very self-conscious in school, for they make
many mistakes in the use of the English language and are
concerned about being ridiculed. Moore (1965, p. 56)
explains that "when poverty is accompanied by language
difficulties, small success with school work and rejection
by other classmates, the situation [for the development of a
positive self-concept] eventually grows hopeless." Accord—
ing to John and Horner (1970), if migrant children speak
primarily Spanish, and teachers in school speak primarily
English, these children are being taught all subject matter
in an alien cultural and linguistic milieu.

Through the years educators have offered various ex-
planations and solutions to the problem of educating the
Chicano child. Few have provided the child with as bene-
ficial an education as that received by the Anglo—American
child. On one extreme, educators have chosen to completely
disregard the cultural differences between the Spanish—
speaking and the English-speaking children while others
have assumed that the Spanish-speaking children in the
United States are as foreign as the Mexican children of
Mexico. Various investigators have studied the problems
associated with bilingual education in the United States.

Although most educators (Garretson, 1928; Haught, 1931;

21

Spoerl, 1943; Arsenian, 1945; UNESCO, 1951: Holland, 1960;
and John and Horner, 1970) support the need for bilingual
programs, few programs have as yet been initiated. Since
the recognition of the need for bilingual programs in the
late 1920's, Chicano children have continued to fear the
lack of recognition and understanding from teachers whose
backgrounds are dissimilar and who misinterpret many of
the children's efforts to achieve success and accommodate
themselves to basically alien demands.

One aspect which thus far has not been largely in-
vestigated is that many children who have language diffi-
culties in school and who come from families of low-socio-
economic backgrounds may also have a hearing loss. These
children, as explained above, tend to receive poorer medical
treatment than "middle class" and urban children; they
tend to live in poorer housing conditions, and they usually
lack proper nutrition. In view of the investigations pre-
sented earlier, many of these children could have difficulty
learning English because of conductive hearing losses which,

due to lack of medical attention, have gone undiagnosed.

Statement of Purpose

In view of the high incidence of middle ear problems
detected in various socio-economically depressed communities,
this study was undertaken to investigate the following ques-

tions: (1) Is there a higher incidence of middle ear

22

pathology among Chicano migrant workers than in the general
pOpulation? (2) Is there a higher incidence of hearing loss?
(3) How do the hearing threshold levels of the children of
Chicano migrant agricultural workers compare with the data
presented by Eagles et al. (1963) and the United States
Department of Health Education and Welfare (1970)?

(4) How do the hearing threshold levels of the adult Chicano
migrant workers compare with the data presented by Corso
(1963)? and (5) If ear problems are found in this popula—

tion, does the incidence decrease as a function of age?

CHAPTER II

EXPERIMENTAL PROCEDURES

Subjects

Sixty subjects, 37 children and 23 adults, selected
from two migrant camps during August, 1971 participated in
the study. The children ranged in age from 5-16 years with
a mean age of 9.8 years. All children over the age of four
years, living in these two camps, were tested. The adults
ranged in age from 18-50 years with a mean age of 28.9
years. The adults sample, however, consisted of approxi—
mately 3/4 of the adult population in the camps. All
adults who were willing to be examined were included in the
study. The sixty subjects were members of thirteen differ—
ent families. The size of the smallest family tested was
one person while the size of the largest family was ten
people, with a mean of 4.6 people. The subjects were liv—
ing and working in typical conditions for Chicano migrant

agricultural workers as described in Chapter I.

Equipment

All threshold tests were conducted in one room of a

two-room testing suite with both the experimenter and the

23

24

subject in a single—walled sound—treated room housed in a
Vagabond trailer shell. The other room was used by the
otolaryngologist for the medical examination. The single-
walled room was sound treated with one layer of fiberglass,
followed by a four inch dead space, covered with fiberglass
and burlap material. The floor was also treated using dead
air space and then covered with carpeting. The only exterior
window contained three pieces of plexiglass separated from
one another by one inch dead air spaces. The ambient noise
level in the test chamber was 40 dB sound pressure level
(SPL) measured on the C scale of a sound level meter (Brfiel
and Kjaer type 2204-8) using a sound—field condenser micro-
phone (Brfiel and Kjaer type 4145). This sound level meter
was calibrated using a pistonphone (Brfiel and Kjaer type
4220). Noise levels were also measured at octave intervals
by attaching an octave band filter set (Brfiel and Kjaer type
1613) to the above mentioned equipment. The ambient noise
was sufficiently low at all test frequencies, according to
the ASA (1960) Criteria for Background Noise in Audiometer
599mg, so as not to interfere with pure—tone threshold
measurements. See Appendix A. The difference between the
ASA and the ISO norms was used as a correction factor in
determining acceptable levels of ambient noise.

Pure-tone air—conduction thresholds were obtained using
a commercial audiometer (Beltone 15 C) with earphones
(Telephonics TDH 39 102) mounted in MX 41/AR cushions.

Bone-conduction thresholds were also obtained with the Beltone

audiometer, employing a bone oscillator (Radioear B 70 A).
Broad band white noise, calibrated in effective masking,
was used whenever masking became necessary. The air-
conduction system was calibrated daily during the course of
the investigation with an artificial ear assembly (Brfiel
and Kjaer type 4152) and a condenser microphone (Brfiel and
Kjaer type 4144) with the associated sound level meter
(Brfiel and Kjaer type 2204-8) and octave band filter net—
work (Brfiel and Kjaer type 1613). The initial calibration
of the bone oscillator was obtained using an artificial
mastoid (Beltone type M5A), a mastoid amplifier (Beltone
type M5A), and a microphone amplifier (Brfiel and Kjaer type
2603). Thereafter, the bone-conduction system was cali-
brated biologically prior to each test session with one
normal hearing subject to ascertain that the calibration of
bone conduction was in agreement with air conduction. All
threshold measurements (air- and bone—conduction) were made
with 20 dB attenuation pads inserted in the system between
the audiometer and the transducers. The attenuation of
these pads was measured for both air and bone-conduction at
each frequency, and the necessary corrections were then made.
No systematic changes were found in the output of the audio-

metric equipment during the course of the investigation.

Tests and Procedures of Administration

Pure—tone air— and bone—conduction thresholds were
measured in 5 dB steps using the Hughson-Westlake ascending
technique recommended by Carhart and Jerger (1959). The
following frequencies were tested by air—conduction: 1000,
2000, 4000, 6000, 8000, 1000, 500, and 250 Hz. Test—re-test
was accomplished according to Witting and Hughson (1940) at
1000 Hz. Ears were alternated as to which ear was tested
first. The frequencies tested by bone-conduction were 1000,
2000, 4000, and 500 Hz. Bone-conduction thresholds were
obtained unmasked. If an air—bone gap of 10 dB or greater
was obtained, the Studebaker (1964, 1967) method of masking
the non-test ear was employed to obtain a masked threshold.
Both ears were tested by air and bone-conduction for all
subjects. The subjects responded by raising their hand

whenever they perceived a tone through the earphone.

Otolarynggiogical Examination

The otolaryngologist conducted an ear, nose, and throat
examination on 68% (N=25) of the children and 65% (N=15) of
the adults who were audiometrically tested. These subjects
were randomly selected from the total sample. This exami-
nation was conducted in the outer room of the two-room test

suite.

Interview

 

Two bilingual individuals capable of speaking both
Spanish and English, served as interviewers and interpretm
ers. Almost all the interviews were tape recorded on
compact cassette tapes using a tape recorder (Norelco
Cassette EL 3302). Interview information was obtained for
all subjects. Many of the conversations were in English
while some were totally in Spanish. The interview was con—
ducted immediately prior to both the otological and audio-
logical examinations. The otolaryngoloqist was then able
to refer to the interview sheet before proceeding with his
examination. The audiologist did not refer to any of the

already obtained information prior to the hearing test.

Forms

The packet of forms used for this investigation in—
cluded: (l) and (2) a Questionnaire in both English and
Spanish containing eleven questions, several questions having
more than one section; (3) a Physical Examination check—off
form; (4) a Physical Examination Impressions sheet to record
the need for referral and brief description of the problem
if one was observed; and (5) an Audiogram plotted in dB re:

ISO (1964). See Appendix B.

CHAPTER III

RESULTS AND DISCUSSION

This investigation included an interview with each
subject or subject's parent, an ear, nose, and throat exami—
nation of 68% of the children and 65% of the adults, and
for all subjects a pure-tone air- and bone-conduction audio-

metric evaluation.

Interview

 

The initial data obtained was the subjective informa-
tion supplied at the interview and can be found in Tables
1 and 2. According to the respondents, there was not
thought to be a high incidence of hearing loss in the family.
Of the children seen, 27% supposedly had hearing loss while
only 13% of the adults said that a family member was experi-
encing hearing difficulty. It is necessary to recall at
this time that all sixty subjects were members of only thir-
teen families, so if one member of the family had a hearing
loss, all children and adults in that family might have
answered "yes" to the question. When asked if they personal—
ly had difficulty with their hearing, 19% of the children and

13%.of the adults answered in the affirmative. None of the

 

 

 

 

 

 

Table 1. Answers to questions posed to the parents of the
children tested.
ANSWER
QUESTION Yes NO
% N % N
"12 Is there any hearing loss in the
family? 27 (10) 73 (27)
2. Does your child have a hearing
loss? 19 ( 7) 81 (30)
3. Does your child have frequent
colds (5 or 6 per year)? 19 ( 7) 81 (30)
4. Has a doctor ever looked into your
child's ears? 65 (24) 35 (13)
5. Has any liquid run out of your
child's ears? l6 ( 6) 84 (31)
6. Has your child ever had any
severe earaches? 49 (18) 51 (19)
7. Has any medication been taken for
an ear infection? 19 ( 7) 81 (30)
8. Does your child have trouble
hearing speech? 27 (10) 73 (27)
9. Has your child ever worn a hear-
ing aid? 100 (37)
10. Has your child ever had a hearing
test where it was necessary to
listen for tones through earphones? 49 (18) 51 (19)
11. Has your child ever worked around
farm machinery? 46 (17) 54 (20)
12. Has your child ever driven farm
machinery? ll ( 4) 89 (33)
13. Did your child ever wear any ear
protection while working around
the machinery? 3 ( 1) 97 (16)

 

Table 2. Answers to questions posed to adult subjects.

 

 

 

 

 

ANSWER
QUESTION Yes No
% N % N

1. Is there any hearing loss in the

family? 13 ( 3) 83 (19)1
2. Do you have a hearing loss? 13 ( 3) 78 (18)2
3. Is there any ringing in your ears? 30 ( 7) 70 (16)
4. Do you have frequent colds (5 or

6 per year)? 26 ( 6) 74 (17)
5. Has a doctor ever looked into

your ears? 61 (14) 39 ( 9)
6. Has any liquid run out of your

ears? 4 ( 1) 96 (22)
7. Have you had any severe earaches? 39 ( 9) 61 (14)
8. Has any medication been taken for

an ear infection? 9 ( 2) 91 (21)
9. Do you have trouble hearing

speech? 26 ( 6) 74 (17)
10. Have you ever worn a hearing aid? 100 (23)
11. Have you ever had a hearing test

where it was necessary to listen

for tones through earphones? 30 ( 7) 70 (16)
12. Have you ever worked around farm

machinery? 65 (15) 35 ( 8)
13. Have you ever driven farm

machinery? 35 ( 8) 65 (15)
14. Did you ever wear any ear pro-

tection while working around the

machinery? 100 (15)

 

1One subject answered maybe (4%)

2Two subjects answered maybe (9%)

31

children reportedly had experienced any form of tinnitus;
30%.of the adults felt that some type of ringing in the
ear(s) was noted. The tinnitus was reported to be both
low and high pitched and of frequent and infrequent occur-
rence.

Frequent colds were defined as five to six colds per
year; 19% of the children and 26% of the adults supposedly
suffered from this difficulty. It was further recorded
that prior to this study, only 65% of the children and 61%
of the adults had ever had an otoscopic examination by a
physician. Most parents reported that past otoscopic
examinations of their children had taken place during
school registration.

Pathology of the ears was also noted. Forty-nine per-
cent of the children and 39% of the adults had previously
had at some time in their lives severe earaches and 16% of
children and 4% of adults had previously had liquid dis—
charge from the ear. Although they were not able to
identify the types of medication, 19% of the children and
9% of the adults had taken medication for the ear. Many
families further explained that to cure severe earaches,
they used warm olive oil and applied it in the ear with
cotton.

Some individuals, 27% of the children and 26% of the
adults, reported having difficulty hearing conversational
speech. Although, as stated earlier, the percentages of

children and adults who reportedly experienced general

hearing difficulty were much lower than those who said
they had a specific difficulty in hearing speech, it is
the investigator's impression that some parents expressed
concern because their children were not particularly
attentive to verbal statements. None of the children or
adults had ever worn a hearing aid. Forty-nine percent
of the children and 30% of the adults had previously had
their hearing screened or tested audiometrically. Most
of the children who lnmi had a previous hearing test were
of school age and had been tested during school screening
programs. The remainder of the people had been tested at
state funded neighborhood clinics.

Finally, it was reported that 65% of the adults and
46% of the children had worked in the fields close to farm
machinery. Thirty-five percent of the adults and 11%.of
the children had actually personally Operated the equip-
ment. Of the seventeen people who had worked in the
vicinity of farm machinery, only one person, a teenage boy,
reported wearing ear protection. He described the pro—

tectors as some form of earplugs.

Otolaryngological Examination

The otolaryngologist was able to examine only twenty—
five children (68% of the total number) and fifteen adults
(65% of the total number). The results of the physical

examination are presented in Tables 3 and 4.

33

Table 3. Number and percentage of otolaryngological find—
ings for 25 children ages 5-16 years for both
unilateral and bilateral pathology.

 

 

 

 

 

 

 

 

 

 

Unilateral Bilateral
N % N %
Ears
Normal tympanic membrane (TM) (1) 4 (10) 40
Obstructed TM (1) 4 ( l) 4
Retracted TM (2) 8 ( 7) 28
Thickened TM (0) ( 1) 4
Thickened and retracted TM (1) 4 ( l) 4
Inflamed TM (including secre-
tory otitis media) (1) 4 ( 2) 8
Total ‘3) 12 (22) 88
Nose
Normal (0) (20) 80
Mucous membrane thickening (0) ( 5) 20
Total (0) (25) 100
Neck Glands
Not palpably abnormal (18) 72
Palpably but not markedly enlarged ( 7) 28
Total (25) 100
Tonsils
Normal (17) 68
Hypertrophied ( 7) 28
Scarring and retraction moderate ( l) 4
Total (25) 100
Pharynx
Normal (21) 84
Chronic lymphoid hyperplasia 1,41, 16

 

Total (25) 100

 

34

Table 4. Number and percentage of otolaryngological find—
ings for 15 adults ages 18-401 years for both
unilateral and bilateral pathology.

 

 

 

 

 

 

 

Unilateral Bilateral
N % N %
Ears
Normal tympanic membrane (TM) (1) 6.5 ( 3) 20
Obstructed TM (1) 6.5 ( 0)
Retracted TM (2) 13.0 ( 9) 60
Thickened TM (0) ( l) 7
Total (2) 13 (13) 87
_________________________ 1____________-___-_______--__-_____
Eggs.
Normal (0) (13) 87
Mucous membrane thickening (0) ( 2) 13
Total (0) (15) 100

Neck Glands

 

 

Not palpably abnormal (14) 93
Palpably but not markedly enlarged ( i) 7
Total (15) 100
Tonsils
Normal (12) 80
Hypertrophied ( 2) 13
Scarring and retraction moderate ( i) 7
Total (15) 100
Pharynx
Normal (13) 87
Chronic lymphoid hyperplasia g 2) 13
Total (15) 100

 

1No adults older than 40 years of age were examined by the
physician.

35

Of those examined, normal tympanic membranes were
noted bilaterally in 40% of the children and 20% of the
adults and unilaterally in 4% of the children and 7% of the
adults. Tympanic membranes obstructed by cerumen were seen
only infrequently, bilaterally only 4% in children and
unilaterally 4% in children and 7%.in adults. Retracted
tympanic membranes were, however, much more common.
Twenty-eight percent of the children and 60% of the adults
were found to have bilateral retractions, and 8% of children
and 13% of adults had unilateral retraction. For adults,
tympanic membrane retraction was the highest observed ab-
normal ear, nose, and throat condition while for children
it was one of the three highest ENT abnormalities.

Thickened membranes were noted bilaterally in 4%.of the
children and 7% of the adults. In children thickening and
retraction were infrequently noted concurrently; 4% uni-
laterally and 4% bilaterally. Inflamed membranes including
the possibility of secretory otitis media were not found
for any adults and only infrequently in children. Eight
percent demonstrated this pathology bilaterally and 4%
unilaterally.

Ear involvement was the most frequent otolaryngological
abnormality found in this investigation. Of the 25 children
who received the otosc0pic examination, 60% had at least a
unilateral abnormality; forty-eight percent demonstrated

bilateral pathology. Of the 15 adults who received the

36

otoscopic examination, 80% had at least a unilateral ab-
normality; 67% demonstrated bilateral pathology.

Examination of the nose revealed that 80% of the
children and 87% of the adults had normal conditions bi-
laterally. Mucous membrane thickening was noted bilateral-
ly for 20%lof the children and 13% of the adults.

Neck glands were found to be "not palpably abnormal"
for 72% of the children and 93%.of the adults. Twenty-eight
percent of the children and 7% of the adults had glands
which were palpably but not markedly enlarged.

Normal tonsils were noted in 68% of the children and
80%.of the adults. Other conditions observed were hyper-
trophy occurring in 28% of the children and 13% of the
adults and scarring and moderate retraction in 4% of the
children and 7% of the adults. Total percentage of tonsils
which showed other than normal conditions was 32% for the
children and 20%.for the adults.

The pharynx was found to be normal for 84%.of the
children and 87% of the adults. Chronic lymphoid hyperplasia
was noted in 16% of the children and 13%.of the adults.

Only one adult and one child who had been examined
demonstrated an otolaryngological abnormality unaccompanied
by otoscopic abnormality. Sixty-four percent (N=l6) of the
children and 87% (N=13) of the adults receiving the physical
examination demonstrated some type of ear, nose, and throat

pathology, at least unilaterally. Bilaterally, 52% (N=13)

37

of the children and 73% (N=ll) of the adults demonstrated

pathology.
Audiological Evaluation

Children

The age distribution of the 37 children can be found
in Table 5. All ages were represented from five to sixteen
years, although no uniform number of children was tested at
each age level. The reason for this was the limited number
of children available for testing. Except for the children
below age 5 years, all children living at both migrant camps
were tested.

None of the mean or median air-conduction hearing
thresholds in dB re: ISO (1964) for all children ages 5-16
years (refer to Table 6 and Figure 1) reached 0 dB HL at any
frequency in either ear. The mean audiometric configurations
appeared relatively flat for both ears, having exhibited an
inter-frequency range of 8.9 dB (from 7.3 dB HL to 16.2 dB
HL) for the right ear and an inter-frequency range of 5.7
dB (from 11.1 dB HL to 16.8 dB HL) for the left ear. It
should be pointed out that Table 6 presents both mean and
median data. Figures 1-6 display only means, while later
comparisons are expressed using medians. This change in
examination of the data was done in order to relate this in-
vestigation to the available data from the comparison studies
(Eagles et al., 1963; United States Health Education and

Welfare, 1970).

38

Table 5. Age distribution of children audiometrically

 

 

 

tested.

Age in Years Total Number
5 2
6 6
7 5
8 5
9 l

10 2
11 4
12 2
13 2
l4 4
15 2
l6 2

 

39

 

 

Table 6. Mean, median, range, and standard deviation of
air-conduction thresholds in dB re: ISO (1964)
and air-bone gap data for all children ages 5-16
years classified by frequency and ear tested.
== E:
Frequency (Hz) ‘W250 500 1000 2000 4000 6000 8000
Right Ear
Mean 16.2 12.3 7.3 8.6 14.2 15.4 15.0
Median 15 10 5 10 15 15 15
Range 25 25 30 30 30 45 50
Standard Devia-
tion 7.1 6.3 8.6 5.8 8.1 10.5 13
Left Ear
Mean 14.6 13.4 11.1 11.9 16.8 15.9 13.9
.Median 10 10 10 5 15 15 10
Range 40 55 60 55 55 65 50
Standard Devia-
tion 10.9 10.9 12.0 13.0 12.7 14.3 12.5
Air—bone gap 11.1 5.4 5.9 8.1

 

40

 

 

 

 

 

a RIGHT EAR

"" 250 500 1000 - 2000 40.00 6000 8000
3 , _ . . _
5::

u-‘l g 0

‘UH

'5' o

'53 10

0

H a; .“ 1‘.‘ .- a.

'55 20 «#5 .

m .

c: m

«to

:3 30 .

(D

m Frequency in Hz

0 right ear air-conduction threshold
x left ear air-conduction threshold

LEFT EAR
250 500 1000 2000 4000 6000 8000

; - .g WA,
"' ‘- _ , 1" In": q ' I w . . ‘4’“ I
\ " ' ’

 

 

ISO 1964)

dB (re:

 

 

Hearing Threshold Level in

Frequency in Hz

Figure 1. Mean air-conduction hearing threshold levels in
dB re: ISO (1964) for all children ages 5-16 years, includ-
ing one standard deviation, by frequency and ear tested.

41

Both right and left ear mean air—conduction audiograms
for the children were within normal limits for all fre-
quencies tested. Thresholds within one standard deviation
of the mean for the right ear were within normal limits
except at 6000 and 8000 Hz. Within one standard deviation
of the mean, thresholds for the left ear at 250, 4000, 6000,
and 8000 Hz were beyond the acceptable limits for normal
hearing according to the ISO norm. Some thresholds for the
speech frequencies (500, 1000, and 2000 Hz) for the left
ear, within one standard deviation of the mean, were only
within the limit for borderline normal hearing.

The air-conduction audiometric configuration for the
left ear was flatter than the configuration for the right
ear. Mean hearing threshold levels at all frequencies for
the right and left ears were very similar. The largest dif—
ference was 3.8 dB at 1000 Hz, and the smallest was 0.5 dB
at 6000 Hz. The right ear had minimally better thresholds
than the left ear at all frequencies except 250 and 8000 Hz.

Very few children had air—conduction thresholds better
than audiometric zero re: ISO (1964). Figures 2, 3, and 4
show the percentage distribution of hearing levels for all
children ages 5-16 years classified by ear and frequency.
Threshold curves at all frequencies were skewed to the right
of 0 dB HL, indicating poorer hearing than the norm. Unlike
the United States Public Health Study (1970, p. 8), the
curves plotted in Figures 2 and 3 of this investigation did

not follow similar patterns for each frequency. Even when

42

 

 

 

 

 

 

 

 

 

 

 

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48

combining ears (see Figure 4) to obtain an N = 74 ears at
each frequency, the curves still did not appear to have
normal distributions. Perhaps more consistent inter—
frequency results would have been obtained with a larger
number of subjects.

Mean air-bone gaps were present for both ears at all
frequencies 500-2000 Hz (Figure 5). Both right and left
ears demonstrated clinically significant air-bone gaps
(greater than 7 dB at 250 and 4000 Hz). Borderline sig-
nificant gaps of 5.4 dB and 5.9 dB respectively at 1000 and
2000 Hz were also present in the left ear. At all frequen-
cies, the left ear had greater air-bone gaps than did the
right ear. For both ears, the air—bone gaps appeared to be
greater at the low and high ends of the frequency region
with less of a gap for the mid frequencies. Again, it
should be mentioned that although mean air-bone gaps were
present at each frequency for both ears, all mean air-
conduction thresholds were within normal limits re: ISO
(1964).

The 25 children ages 5-16 years who received the
otolaryngological examination were divided into two groups,
those with normal medical examination results (9 children)
and those with abnormal results (16 children). Those children
considered normal showed no signs of the following patholo-
gies: (1) obstructed, retracted, thickened or inflamed

tympanic membrane; (2) secretory, acute, or chronic otitis

49

 

 

 

 

 

 

 

 

 

 

 

q RIGHT EAR

'H 250 500 1000' 2090 4000 6000 8000
7’ l

is z; I l | I

..1 o o +__

a 3 .

2 a; < ‘ P
54:; 20 ____

2‘

..4 53

g -30

g Frequency in Hz

G LEFT EAR

'” 250 590 1000 2000 4000 6000 8000
'3

as; l l l l |

..1 g o ..___

'd H

....

~2Eg 10-—___

n+4

0

B 3

Egg 20»———-

2‘3 '

+3 ‘ 30

g Frequency in Hz

right ear air-conduction threshold
left ear air-conduction threshold
right ear bone-conduction threshold
left ear bone-conduction threshold

“fly—3x0

Figure 5. Mean hearing threshold levels in dB re: ISO (1964)
‘by air- and bone—conduction for all children ages 5-16 years
by frequency and ear tested. Shaded area is the air-bone gap°

media: (3) dry or wet perforation of the tympanic membrane;
(4) congenital atresia; (5) external otitis; (6) nasal
septum obstruction; (7) nasal mucous membrane thickening;
(8) acute or allergic rhinitis; (9) purulent discharge of
the nose: (10) polyps; (ll) polyps and purulent discharge;
(12) enlarged glands; (l3) tonsil tags (infected or non-
infected): (14) hypertrOphy of the tonsils; (15) acute or
chronic infection of the tonsils; (16) scarring and moder—
ate retraction of the tonsils: (l7) granular pharyngitis;
and (18) chronic or severe lymphoid hyperplasia of the
pharynx. All children with abnormal otolaryngological exam-
ination results showed at least one of the above described
pathologies, while some children demonstrated up to six
different pathological conditions. Six children showed one
abnormal condition, two children each had two, three, four,
and five pathologies, and one demonstrated six abnormal
conditions.

Mean air-conduction hearing threshold levels for
children with both normal and abnormal examination findings
haverbeen plotted in Figure 6 for separate ears. Both right
and left ears showed better hearing at all frequencies for
those children with no evidence of pathology. When compar-
ing the audiometric configurations of the two sub-groups,
the left ear thresholds at each frequency (refer to Figure 6)
appeared to have more clinically significant threshold differ-

ences than the thresholds for the right ear° This was true

51

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

RIGHT EAR
_. 250 500 1000' " 2000 4000 6000 8000
g l
m
A
....
00‘
43—4
3
H8
Era
ma;
GL4
"4V
‘3
fit 30

Frequency in Hz

LEFT EAR
.q 250 500 1000 2000 4000 6000 8000
g [ l
0
q .
35:? 0““
.22: ,{3_ —"""§'-—""flc>\\‘\

“" \
fig 127/ \A’ “A
'5“ °
. '1‘ L m

(N3 ZOQi____ 41‘ REIJ 1'j‘‘“t~~~~E7"—-—---E}//tJ
CH
...-[v
33
m 30
m

Frequency in Hz

A Normal D[ Abnormal

 

Figure 6. Mean air—conduction hearing threshold levels in
dB re: ISO (1964) for the 25 children who received the
otolaryngological examination, separated by ear into two
groups: otolaryngologically normal and abnormal.

for all frequencies except at 8930 Hz where the right ear
threshold showed a greater discrepancy.

Those children with normal otolaryngological findings
did not have mean air-conduction hearing threshold levels
for either ear at any frequency that were better than 0 dB
HL re: ISO (1964). However, the mean threshold levels for
both ears ranged from 2—14 dB HL, the best thresholds being
at the frequencies 500-2000 Hz bilaterally. For those sub-
jects with abnormal ear, nose, and throat findings, the
mean threshold levels for both ears ranged from 10-22 dB HL.
For the right ear, their mean hearing levels appeared best
at frequencies 500—1000 Hz. The left ear, however,
demonstrated a relatively flat configuration from 250—2000
Hz with a slight threshold dip at 4000 and 6000 Hz, recover-
ing again at 8000 Hz.

To determine the relative significance of the air-
conduction threshold data and the otolaryngological findings
for the children of this investigation, the results were
compared to the Eagles et al. (1963) and the United States
Health, Education, and Welfare (1970) surveys. It is rele-
vant to explain that these three studies were not conducted
with the same audiometric norms nor the same earphones and
cushions. The present investigation employed an audiometer
calibrated to the ISO (1964) norm with the Telephonics TDH
39 earphone mounted in an MX 41/AR cushion. Eagles at al.
(1963) determined all threshold levels re: ASA (1951) using

the Western Electric 705 A earphone. The United States

53

Department of Public Health, Education, and Welfare study
(1970) used, for its investigation, the ASA (1951) norm
employing the TDH 39 earphone in the MX 4l/AR cushion.

In order to compare these three different studies, all
median air-conduction data was converted from hearing level
to the sound pressure level scale re: 0.0002 dyne/cmz. The
median sound pressure level thresholds (refer to Table 7)
were then converted once again to reach the values of the
Western Electric 7OSIxearphone at each frequency according
to Cox and Bilger (1960). (See Appendix C for the various
’SPL differences for both earphones and audiometric norms.)
Median data were compared because there was no available
mean air-conduction data for the United States Health Edu-
cation and Welfare (1970) study. Comparative air-conduction
audiograms in dB re: ISO (1964) using the values for the
Western Electric 705 A earphone were then plotted for
separate ears at each test frequency according to the con-
version data presented by Davis and Krantz (1964). To com—
pare the data of the three studies, refer to Figures 7 and 8.

The air-conduction thresholds of the Eagles et a1. (1963)
and the United States Health Education and Welfare (1970)
studies were in agreement with one another within :2.5 dB
bilaterally at all frequencies except 2000 and 6000 Hz for
the right ear and 6000and 8000 Hz for the left ear. For the
right ear, the Eagles study showed a poorer median threshold
by 3 dB at 2000 Hz, and the United States Health Education

and Welfare study was poorer by 3.5 dB at 6000 Hz. For the

54

Table 7. Median air—conduction hearing threshold levels in
dB re: 0.0002 microbar using values for the
Western Electric 705 A earphone for the migrant
children tested and for the children tested by
Eagles et a1. (1963) and the United States Depart—
ment of Health Education and Welfare (1970), clas-
sified by frequency and ear tested.

 

 

 

 

Frequency Present U. S. Dept.
(Hz) Study Eagles et al. of Health
Right Ear
250 39.5 30.8 31.2
500 21.0 17.9 17.2
1000 11.5 11.1 9.7
2000 18.5 12.3 9.3
4000 24.0 10.7 11.6
6000 23.0 13.4 16.9
8000 24.5 17.2 16.8
Left Ear
250 34.5 29.9 31.5
500 21.0 17.9 17.4
1000 16.5 11.1 9.7
2000 13.5 11.8 9.6
4000 24.0 11.1 12.0
6000 23.0 14.0 17.8
8000 19.5 16.8 13.0

 

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57

left ear, the United States Health Education and Welfare
data was poorer by 3.8 dB at 6000 Hz and the Eagles data
was poorer by 3.8 dB at 8000 Hz. ‘

The air—conduction hearing levels of the present study,
although within normal limits, generally fell below the
threshold levels of the comparative studies. For the
right ear, the only frequency which was not poorer than
2.5 dB was at 1000 Hz. This threshold was within 0.4 dB
of the Eagles et al. (1963) study and 1.8 dB of the United
States Health Education and Welfare (1970) study. For the
left ear, data obtained at 2000 Hz for this investigation
was close, within 2.0 dB, to Eagles‘ data.

The air-conduction thresholds presented above demon-
strated that there were a few frequencies with agreement
between this study and the two studies chosen for compari-
son. There were, however, other frequencies at which large
discrepancies in thresholds occurred with poorer hearing
for the present study. Observing the right ear thresholds
(Figures 7 and 8), it is apparent at 2000 Hz that the
median threshold was 9.2 dB poorer than the threshold for
the United States Health Education and Welfare (1970) study
and at 4000 Hz it was 13.3 dB poorer than the threshold of
the Eagles et al. (1963) study. At 4000 Hz, for the left
ear, the Eagles et al. (1963) threshold level was 12.9 dB
better than the obtained median threshold for this investi-

gation.

58

Adults

Four adult age groups, for a total of 23 subjects,
were also tested audiometrically in this investigation
(see Table 8). The groups were divided by age so that
they resembled the age groups tested by Corso (1963).
Nine people were tested in the age group 18-24 years, six
in the age group 25-33 years, five at 33-40 years, and
three at 43-50 years. None of these groups was divided
equally by sex. The sample comprised all adults between
the ages of 18—50 years that were willing to be tested in
two migrant housing camps. Approximately 75% of the adults
present in the camps were willing to be examined.

The pure-tone air—conduction thresholds for all adults,
ages 18—50 years, are displayed in Tables 9, 10, 11, and
12 and Figures 9 and 10. The findings demonstrated that
the best thresholds for all age groups were at 1000 and
2000 Hz bilaterally. None of the mean hearing thresholds
in dB re: ISO (1964) reached 0 dB HL at any frequency in
either ear. For those in the age group 18-24 years, the
mean audiometric configurations were generally flat for both
ears, although decreased hearing acuity was exhibited at the
low and high frequencies. The right ear exhibited an inter-
frequency range of 11.6 dB (from 5.0 dB HL to 16.6 dB HL)
and the left ear an inter—frequency range of 15.1 dB (from
5.5 dB HL to 20.6 dB HL). The inter-frequency range for
this age group was greater bilaterally than the range found

for the children.

59

Table 8. Age distribution of adults audiometrically tested.

 

 

Age in Total
Years Number

 

18
19
20
21
22
24

Sub Total (5 female; 4 male)
25
26
28
30
32

Sub Total
33
:37

38
40

Sub Total

(5 female: 1 male)

(3 female: 2 male)

43
45
50

Sub Total

LHFHH mkwuuaoflwwwww~okwwwmm

(1 female; 2 male)

 

Total

N
w

 

Table 9.

Mean,

median,

range,

60

air-conduction thresholds in dB re:

and standard deViation of
ISO (1964)
and air—bone gap data for adults ages 18-24

years classified by frequency and ear tested.

 

 

 

 

Frequency (Hz) 250 500 1000 2000 4000 6000 8000
Right Ear
Mean 16.6 13.8 5.5 5.0 10.0 13.8 11.1
Median 15 15 5 5 5 10 5
Range 20 20 20 20 20 55 40
Standard Devi-

ation 7.1 5.7 6.0 7.8 4.6 15.4 11.0
Air—bone Gap 9.4 2.8 3.9 6.1
M
Mean 15.0 10.0 5.5 6.6 11.7 15.0 20.6
Median 15 10 5 10 15 15 20
Range 25 20 25 25 25 35 40
Standard Devi-

ation 2.1 1.9 1.9 7.1 7.8 9.1 11.7
Air-bone Gap 10 3.9 7.2 7.2

 

Table 10. Mean,

median,

range,

air—conduction thresholds in dB re:

and standard deviation of
ISO (1964)
and air—bone gap data for adults ages 25—32

years classified by frequency and ear tested.

 

 

 

Frequency (Hz) 250 500 4000 6000 8000
Right Ear
Mean 13.3 10.8 12.5 15.0 15.8
Median 10 12.5 12.5 15 15
Range 20 20 15 20 20
Standard Devi-

ation 6.9 7.1 4.8 5.7 7.3
Air—bone Gap 5.8 3.3
Left Ear
Mean 12.5 8.3 3 3 10.8 17.5 14.2
Median 12.5 5 2 5 12.5 15 12.5
Range 15 20 0 20 25 30
Standard Devi-

ation 4.8 6.9 6 3 6.7 8.1 16.2
Air-bone Gap 7.5 l 7 0.8

 

Table 11. Mean,

median,

range,

62

air-conduction thresholds in dB re:

and standard deviation of
ISO (1964)
and air-bone gap data for adults ages 33—40

years classified by frequency and ear tested.

 

 

 

 

Frequency (Hz) 250 500 1000 2000 4000 6000 8000
Right Ear
Mean 23 22 14 17 34 35 27
Median 20 20 10 20 35 40 25
Range 35 45 35 20 50 45 55
Standard Devi-

ation 12.1 16.3 12.4 8.1 17.7 15.8 19.1
Air-bone Gap 1 0 l 6
Left Ear
Mean 18 13 12 15 32 36 39
Median 15 10 15 15 25 35 40
Range 25 20 15 20 45 40 30
Standard Devi-

ation 9.3 8.1 6 7.1 15.4 17 10.2
Air-bone Gap 1 0 4 2

 

Table 12.

Mean,

median,

range,

63

air-conduction thresholds in dB re:

and standard deviation of
ISO (1964)
and air-bone gap data for adults ages 43-50

years classified by frequency and ear tested.

 

 

 

 

Frequency (Hz) 250 1000 2000 4000 6000 8000
Right Ear
Mean 10 6 6.7 3.3 11.7 16.7 5
Median 10 5 5 5 15 15 0
Range 10 5 5 5 10 15 15
Standard Devi-

ation 4.1 2 2 2.2 1.0 4.7 5.8 5.7
Air-bone Gap 1 7 1.7 1.7 1.7
Left Ear
Mean 10 6 6.7 11.7 15.0 21.7 8.3
Median 10 5 5 10 10 25 15
Range 10 5 15 15 25 10 20
Standard Devi-

ation 4.1 2.2 4.8 6.2 10.8 4.7 9.4
Air-bone Gap 1.7 3.3 1.7 5

 

64

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65

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mumum ovnmm mam shag mama» «Numa

66

For those in the age group 25-32 years, the mean air-
conduction audiometric configurations were similar for both
ears at low and mid frequencies with somewhat poorer hearing
bilaterally at 4000-8000 Hz. Thresholds for this age group
were all within normal limits; again the best thresholds were
at 1000 and 2000 Hz. The inter-frequency range for the
right ear was 10.8 dB (from 5.0 dB HL to 15.8 dB HL) and for
the left ear 12.5 dB (from 5.0 dB HL to 17.5 dB HL). This
age group had an inter-frequency range of threshold levels
similar to the 18-24 year age group.

The mean air-conduction audiometric configuration for
those in the age group 33-40 years demonstrated a mild but
clinically significant hearing loss bilaterally in the higher
frequencies (4000-8000 Hz). All thresholds from 250-2000 Hz
were within normal limits bilaterally while thresholds from
4000—8000 Hz showed a mild hearing loss bilaterally. Thres-
hold levels were best for the right ear at 1000 and 2000 Hz
and for the left ear at 500-2000 Hz. All hearing levels were
poorer bilaterally than those for the younger adults. The
decibel range between frequencies for the right ear was 20 dB
(from 14 dB HL to 34 dB HL) and for the left ear 27 dB (from
12 dB to 39 dB HL). The inter-frequency range of threshold
levels was larger for this group than for the previous two
adult age groups.

Results for adults in the age group 43-50 years were

somewhat unusual. All air-conduction thresholds were within

67

normal limits bilaterally and the audiometric configuration
was generally flat, dipping at 6000 Hz and recovering at
8000 Hz bilaterally. The best threshold for the right ear
was at 2000 Hz while the better thresholds for the left ear
were at 500 and 1000 Hz. The inter-frequency range for the
right ear was 13.4 dB (from 3.3 dB HL to 16.7 dB HL) and
for the left ear 15 dB (from 6.7 dB HL to 21.7 dB HL).
These inter—frequency ranges more closely resembled those
of the age groups 18—24 years and 25-32 years than that of
the 33-40 year old group. It should be recalled, however,
that there were only three subjects in this age group and
that two of the subjects were from the same family.

Figures 9 and 10 display the mean air—conduction thres-
holds and the ranges for right and left ears for all adults
separated by age groups. The ranges and standard deviations
(see Tables 9-12) demonstrate the variability in thresholds
for the various age groups. However, because of the small
sample size, when the adult sample was broken into sub-groups,
it is felt that the most appropriate analysis was simply to
view the changes in hearing as a function of age.

Mean air-bone gaps were present for both ears at all
frequencies 500-2000 Hz (see Figure 11). None of the mean
air-bone gaps for either ear appeared clinically significant
except at 500 Hz for the left ear. This one mean air-bone
gap was minimally above the acceptable 5 dB test-retest

Variability at a level of 6.7 dB.

68

 

 

 

 

 

 

 

 

 

 

RIGHT EAR
250 500 1000 2000 4000 6000 8000
SF
\9
as
:1
O
m
H
3
H
m 30
'U
c
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3
0 LEFT EAR
I—‘l
g 250 500 1000 2000 4000 6000 8000
.C:
m
3 10
.G ,
B .j
3‘ 201—-
-a
H
‘8
m .30
Frequency in Hz

0 = air-conduction right ear

X = air-conduction left ear

[ = bone-conduction right ear

] = bone—conduction left ear

Figure 11- Mean thresholds in dB re: ISO (1964) by air-
and bone-conduction for all adults ages 18-50 years by _L
frequency and ear tested. Shaded area is the air-bone gap.

69

To determine the relative significance of the air-
conduction threshold data obtained on adult subjects in
this investigation, the Corso (1963) study was chosen for
comparative purposes. Again, it is important to note that
thresholds for the two studies were obtained using differ-
ent norms and different earphones. As mentioned previously,
this investigation was conducted using the ISO (1964) norm
and Telephonics TDH 39 earphones mounted in MX 4l/AR
cushions. Corso employed the ASA (1951) norm and Permoflux
FDR-8 earphones mounted in MX 41/AR cushions. When present—
ing the data, Corso (1963, p. 60) expressed his mean air-
conduction values in dB re: 0.0002 dyne/cm2 as measured
according to the ASA (1951) standard in the NBS 9—A Coupler
for the Western Electric 705 A earphone.

Right ear, left ear, male, and female air-conduction
thresholds for Corso (1963), see Appendix D, were combined
for each of the four age groups and expressed in dB re:
0.0002 dyne/cmzm The Corso thresholds were then compared
to the thresholds of the four separate age groups of the
present investigation (see Figure 12) and expressed in dB
re: ISO (1964) for the Telephonics TDH 39 earphone.

When comparing the mean air-conduction data for the age
group 18-24 years, the subjects tested by Corso (1963) had
thresholds that were at least 5.6 dB better at all fre-
quencies 250-4000 Hz, ranging from 5.6 dB at 1000 Hz to
14.2 dB at 250 Hz, than the thresholds obtained during this

investigation. The exceptions were at 6000 and 8000 Hz;

7O

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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71

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subjects for this investigation had a mean threshold that
was 5.4 dB better than that obtained by Corso at 6000 Hz
and at 8000 Hz the mean threshold was 4.7 dB better for
this study.

Air-conduction thresholds for the age group 25-32
years (Corso's data included ages 26—32 years) were again
better at all frequencies 250-4000 Hz for Corso's study.
The difference between thresholds at the above frequencies
for the two studies ranged from 2.8 dB at 1000 Hz to 11.2
dB at 250 Hz. Again, thresholds at 6000 and 8000 Hz were
better for this investigation, 8.4 dB and 11.6 dB respec—
tively.

The age group 33-40 years (Corso's data included ages
34-40 years) showed the greatest mean air-conduction thres-
hold discrepancies of the four age groups. Corso's subjects
had better thresholds at all frequencies ranging from 4.0
dB at 8000 Hz to 24.1 dB at 4000 Hz.

When comparing the mean air—conduction data for the
age group 43-50 years (Corso's data included ages 43-49
years), the subjects tested by Corso had better thresholds
from 250—2000 Hz. The range for the above frequencies was
0.5 dB at 2000 Hz to 7.7 dB at 250 Hz. For the frequencies
4000-8000 Hz, the subjects of the present investigation had
better thresholds than did those of Corso's study. These
threshold differences ranged from 3.7 dB at 14000 Hz to

23.6 dB at 8000 Hz.

73

From the above discussion of the data it can be noted
that generally the adults of all age groups tested in the
present study had poorer mean air—conduction thresholds than
did those individuals evaluated by Corso. This was most
obvious for those persons 33-40 years and least obvious for
those 43—50 years. The audiometric configuration trends
generally obtained by Corso appeared flat from 250-2000 Hz,
mildly—to-markedly leping from 2000 to 6000 Hz, with some
threshold recovery at 8000 Hz. This investigation demon-
strated a stiffness tilt at the lower frequencies with the
best threshold levels at 1000—2000 Hz. Mild-to-marked
sloping also occurred in this study from 2000—8000 Hz, with
a flattening of the configuration at 8000 Hz (except for
the age group 43-50 years) rather than a recovery in thres-
hold level. Thresholds at 6000 and 8000 Hz were generally
better for this study than those thresholds obtained by

Corso (1963).

Referrals

Following the otolaryngological and audiological exami-
ruations of all subjects various types of referrals were made.
Five children and three adults were referred for otologic
treatment. One adult was referred for an audiological evalu—
atirnu it.appeared that he might possibly be a candidate for
Eiliearing aid. Four adults were referred for annual audio—

JIKIical evaluations; their otoscopic examinations were

74
essentially clear of pathology, but their audiometric con—
figurations revealed loss of acuity for the higher fre-

quencies.

Discussion

 

One of the purposes of this thesis was to determine
whether there is a higher incidence of middle ear pathology
among Chicano migrant agricultural workers than in the
general population. Pathology of the ear was found to be
the most frequent of the ear, nose, and throat pathologies
in this investigation. Of the 25 children who received the
otoscopic examination, 60% had at least active unilateral
pathology while 48% demonstrated pathology bilaterally.

This percentage was much higher than the 3.0%.active pathology
found by Eagles et al. (1963). Of the 15 adults examined,
active unilateral abnormality was noted in 80% and bilateral
pathology in 67%. It was not possible to compare the oto-
laryngological results for the adults of this investigation
with those results obtained by Corso. subjects tested in
the Corso study did receive an otological examination; if
they failed they were not included in the audiometrically
screened sample. Corso did find though, that with advancing
age, a progressive increase was noted in the percentage of
persons Who failed to qualify as subjects due to abnormal
otological histories or disorders. This increase in middle

ear pathology rather than a decrease was generally noted for

75

the adults in this investigation. Both of the above age
groups had higher percentages of active ear pathology than
found in the Canadian Indian population (15.7%), in the
Baffin Island Eskimo population (30.8%), or in the New York
Children's Social Service Center (24%). It should be re-
called that the studies referred to above had considerably
larger samples than did the present investigation. This,
in part, might account for the difference in incidence
found.

The other major purpose of this study was to determine
if there is a higher incidence of hearing loss among Chicano
migrant agricultural workers than in the general population.
Those studies chosen to represent "general" threshold hear-
ing levels for children were the Eagles et al. (1963) and
the United States Health Education and Welfare (1970)
studies. The data of the three investigations were con-
verted into ISO (1964) values for the Western Electric 705 A
earphone and then compared. Although thresholds for this
study were poorer than the threshold levels of the comparison
studies, present median threshold hearing levels were within
normal ISO (1964) limits bilaterally.

Since the children, ages 5-16 years, of this investi-
gation were found to have median air—conduction hearing
threshold levels within normal limits re: ISO (1964) at all
frequencies bilaterally (see Table 6 and Figures 7 and 8), it
is most likely not true that the majority of the children

who are experiencing difficulty learning the English language

76

are doing so because of poorer hearing acuity. The most
common signs of secretory otitis media are hearing loss
and inattention (Thorburn et al., 1965, p. 436). It can
therefore be speculated that those few children who did
demonstrate moderate conductive hearing losses due to
secretory otitis media, may be experiencing a problem in
English language acquisition which is related to a hearing
loss. This, of course, would depend upon the time of onset
of the hearing loss and the severity of the loss.

Threshold levels for adults were also investigated
and compared to the Corso (1963) study. This study was
considered to represent "general" threshold hearing levels
for adults. Mean hearing threshold levels were compared
using the ISO (1964) norm for the TDH 39 earphone mounted
in the MX 4l/AR cushion. Corso's data showed generally
better hearing for all age groups from 250-4000 Hz. Better
hearing was noted in the present study at 6000-8000 Hz for
all age groups except the 33-40 year old group which
demonstrated poorer thresholds at these frequencies. The
largest discrepancies in the thresholds of the two studies
were generally at 250 Hz and the smallest at 1000-2000 Hz.
A stiffness tilt was generally apparent in the low frequen-
cies for this study, while poorer thresholds were also noted
in the high frequencies. These reduced thresholds in the
high frequencies generally paralleled those thresholds

obtained by Corso.

77

Air-bone gaps were generally noted for the children,
while insignificant air-bone gaps were demonstrated by
adults. Hearing levels of those with middle ear pathology
were generally in agreement with Kapur (1964), between 10-40
dB HL re: ISO (1964). However, occasionally some subjects
demonstrated air-conduction thresholds poorer than 40 dB HL
with relatively normal bone-conduction.

The findings of this investigation relate closely to
the conclusions of Ling, McCoy, and Levinson (1969) and Fay
et al. (1970) who felt that poor general living conditions
contributed substantially to the incidence of middle ear
disease in children from both rural and urban communities.
At the time of this investigation, the author lived at the
-migrant camps for several days. During this period of time,
many poor living conditions were observed in the camps such
as: (1) common showers and outhouses for a large number of
families; (2) an abnormal amount of flies and insects;
(3) running water in only some of the cabins; (4) insufficient
sleeping accommodations for some families; (5) children eating
meals without washing their hands and face; (6) the trash dump
which was just behind the cabins was a health hazzard where
children were able to hurt themselves on~brok§n glass and
sharp metal objects; and (7) occasional lack of child super-‘
‘Vision when parents left the housing camp on days when
(children were not attending summer school. A further observ—

Eition was that the privately owned camp was in much better

78

condition than the state-run camp. The conditions listed
above are similar to those noted by the studies cited in
Chapter I and are possibly contributing factors to the poor
general health conditions resulting in the high incidence
of middle ear disease among Chicano migrants.

The present investigation did not attempt to trace
each person's migratory pattern, so that the incidence of
middle ear problems cannot be directly compared to climatic
variability. Changes in climate, however, could be affect-
ing the health of migrant workers due to: (l) insufficient
clothing for cold weather; (2) a lack of heating and suf-
ficient insulation in their temporary housing facilities;
and (3) their continued traveling throughout the country
where climatic conditions are known to differ from region

to region.

CHAPTER IV

SUMMARY, CONCLUSIONS, AND RECOMMENDATIONS
FOR FUTURE RESEARCH

Summary

Sixty Chicano migrant agricultural workers, 37 children
and 23 adults, were tested by pure-tone air— and bone-
conduction audiometry, seen for an ear, nose, and throat
examination by an otolaryngologist, and asked to respond
orally to a questionnaire.

This investigation did not demonstrate that middle ear
pathology decreased as a function of age for migrant agri-
cultural workers. Sixty-four percent of the children and
87%.of the adults demonstrated some type of ear, nose, and
throat pathology. This finding was in agreement with Ling,
McCoy, and Levinson (1969) who also found a high incidence
and no significant decrease in otolaryngological pathology
with increasing age.

Although the median air-conduction hearing threshold
levels were within normal ISO limits bilaterally (refer to
Table 7 and Figures 7 and 8), thresholds for the migrant
(fluildren were generally poorer at all frequencies than those

median threshold values obtained by Eagles et a1. (1963) and

79

877‘
5 ...

the United States Health Education and Welfare (1970) study.
At most frequencies, threshold differences between this
investigation and the previous studies were found to be at
least greater than 3.0 dB. At 4000 Hz, the difference was
greater than 12 dB bilaterally.

In the adult sample, air-conduction hearing thresholds
generally became poorer as a function of age, which is in
agreement with results found by Corso (1963). Combined right
ear, left ear, male, and female air-conduction thresholds
for each adult age group were poorer for this investigation
than for the Corso (1963) study. This was most obvious for
the 33-40 year old age group. The audiometric configurations
of the subjects in this study, although poorer, paralleled
closely those found by Corso for the frequencies 1000—8000
Hz. The low frequencies, however, were not parallel, but
showed a stiffness tilt for all age groups in the present
study. Thresholds were consistently poorest at 6000 and 8000

Hz for the adults in both studies.

Conclusions

The results demonstrated that the majority of children
who were found to be otoscopically abnormal had fairly sensi-
tive hearing acuity. This was in close agreement with
Eagles et a1. (1963) who found most otoscopically abnormal
children to have hearing more sensitive than 0 dB HL re: ASA

(1951). The opposite was less frequently true. Only two

81

subjects in this investigation, who had normal ENT findings,
had air-conduction thresholds which were not within the
normal ISO (1964) limits at some frequencies. However, all
categories of otosc0pically abnormal ears did demonstrate
less sensitive hearing levels when compared with otoscopical-
ly normal children.

Similar to the findings of Jordan and Eagles (1961),
Eagles et a1. (1963), Melnick, Eagles, and Levine (1964),
and Kapur (1965), if given alone, neither the otological
examination nor the audiological evaluation provided an accur—
ate estimate of the status of the middle ear for every subject
in this investigation. Seventeen subjects found to be
otoscopically abnormal had hearing levels within normal
limits re: ISO (1964). There were 7 children and 5 adults
who demonstrated bilaterally, and 3 children and 2 adults
who showed unilaterally positive ENT findings accompanied by
normal air—conduction thresholds.

Six children and one adult (8.8% of the total subjects)
demonstrated at least unilaterally, pure—tone air-conduction
averages in the frequency range 500, 1000, and 2000 Hz which
exceeded the limits for normal hearing (25 dB HL re: ISO 1964).
This percentage was considerably lower than the 37.9% found
by Cambon, Galbraith, and Kong (1965), and 27.2% found by
Clifford, Hull, and Gregg (1966), and the 19.8% found by
Fay et al. (1970). Thus, although a higher than usual inci—

dence of middle ear pathology was noted in this study, just

 

 

82

the Opposite was found for the incidence of hearing loss.
Nevertheless, air-conduction thresholds for both children
and adults in the present study were generally found to be
poorer than the comparison studies (Eagles et a1. [1963];
United States Health Education and Welfare [1970]; and
Corso [1963]), but threshold averages for the speech fre-
quencies poorer than 25 dB HL re: ISO (1964) were seen only
infrequently.

In conclusion, there appears to be a high incidence
of middle ear pathology but fairly normal hearing thresholds
among Chicano migrant workers. The results of this investi-
gation may not be applicable to all Chicano migrant workers
nor to the total United States migrant population. The
findings do, however, indicate that because of the high
incidence of middle ear problems among this minority group,
Hearing Conservation Health Programs need to be developed to
prevent pathology from occurring. There is also a need to
provide better otolaryngological and audiological services

for migrant workers in Michigan.

Recommendations for Future Research

In view of the findings of the present study, further
investigation concerning the incidence of middle ear prdblems
of migrant agricultural workers appears necessary. Future
investigations should be concerned with incidence of ear

problems among other minority groups which migrate to harvest

crops. Studies should be conducted in other areas of
Michigan, in other states, and during other seasonal peri-
ods to evaluate threshold fluctuations and ear, nose, and
throat pathologies. Newly obtained data could then be
compared with the findings of the present investigation.
It would also be of interest to obtain threshold levels
and percentages of ear pathology for urban Chicanos who
have never traveled the migrant streams and compare these
findings to those of the present study. A full-scale
otolaryngological/andiological investigation conducted by
the United States Public Health Service would best determine
the general incidence, in the United States, of middle ear
problems of Chicano migrants as well as those of other

migrant agricultural minority groups.

LIST OF REFERENCES

 

LIST OF REFERENCES

Allen, Steve, The Ground I§_Our Table. New York: Double-
day & Co. (1966).

American Standard Criteria for Background Noise in Audi-
ometer Rooms, S 3.1-1960. American Standards Associ- gn-u
ation, 70 East 45 Street, New York, N. Y. 5

 

Anderson, D., The Effect of climate on the incidence of
hearing loss. Journalrof Speech and Hearing Disorders,
30, 66—70 (1965).

Arsenian, S., Bilingualism in the post war world.
Psychology Bulletin, 42, 65-86 (1945).

 

Bowles, G. K., Farm labor adjustments to changing technol-
ogy. In C. E. BishOp (Ed.), Farm Labgriin the United
States. New York: Columbia University Press (1967).

Cambon, K., Galbraith, J. D., and Kong, G., Middle-ear
disease in Indians of the Mount Currie Reservation,
British Columbia. Canadian Medical Journal Association,
93, 1301-1305 (1965).

Carhart, R., and Jerger, J. F., Preferred method for clinical
determination of pure-tone thresholds. Journal of Speech
and Hearing Disorders, 24, 330—345 (1959).

Clifford, S., Hull, R. H., and Gregg, J. B., Survey of dis—
orders of speech and hearing and ear, nose, and throat
pathology among children of the South Dakota Indian
population. Read before the 42nd annual convention,
American Speech and Hearing Association, Washington,
D. C. (November 20, 1966).

Corso, J. F., Age and sex differences in pure-tone thres-
holds. Archives of Otolaryngology, 77, 385-405 (1963).

Cox, J. R. and Bilger, R. C., Suggestion relative to the
standardization of loudness-balance data for the Tele-
phonics TDH 39 earphone. Journal of the Acoustical
Society of America, 32 (8), 1081-1082 (1960).

85

86

Davis, H. and Krantz, F. W., The international standard ref-
erence zero for pure-tone audiometry and its relation
to the evaluation of impairment of hearing. Journal of
Speech and Hearing Research, 7, 7—16 (1964).

Eagles, E. L., Wishik, S. J., and Doerfler, L. G., Hearing
sensitivity and related factors in children.
Laryngoscope Suppl., 73 (June, 1963).

Farrant, R. H., The audiometric testing of children in schools
and kindergarten. Journal of Auditory Rpgearch, 1, 1-14

Fay, T. H., Hochberg, 1., Smith, C. R., Rees, N. S., and
Halpern, H., Audiologic and otologic screening of
disadvantaged children. Arch. Otolaryngglogy, 91,
366-370 (1970).

Field Stugy of Migrant Workers in Michigan: Repprt and Recom-
mendationg. Michigan Civil Rights Commission (1969).

Garretson, O. K., A study of causes of retardation among
Mexican children in a small public school system in
Arizona. Journal of Educational Psychology, 19, 31-40
(1928).

Haught, B. F., The language difficulty of Spanish-American
children. Journal of Applied Psychology, 15, 92-95
(1931).

Holland, W. R., Language barrier as an educational problem
of Spanish—speaking children. Exceptional Children,
27, 42-50 (1960).

John, V. P., and Horner, V. M., Bilingualism and the Spanish-
speaking child. In F. Williams (Ed.), Language and
Poverty. Chicago: Markham Publishing Co. (1970).

Jordan, R. E., and Eagles, E. L., The relation of air con-
duction audiometry to otological abnormalities. Annals
of Otglogy, Rhinology and Laryngology, 70, 819-827
(1961).

Kapur, Y. P., Serous otitis media in children. Arch.
Otolaryngology, 79, 38-48 (January, 1964).

 

Kapur, Y. P., A study of hearing loss in school children in
India. Journaliof Speech and Hearing Disordepg, 30,
225-233 (1965).

Koch, Wm. H., Dignity of Their Own. New York: Friendship
Press (1966).

 

Ling, D., McCoy, R. H., and Levinson, E. D., The incidence
of middle ear disease and its educational implications
among Baffin Island Eskimo children. Canadian Journal
of Public Health, 60, 385—390 (1969).

Melnick, W., Eagles, E. L., and Levine, H. S., Evaluation
of a recommended program of identification audiometry
with school-age children. Journal of Speech and Hear—
ing Disorders, 29, 3-13 (1964).

Migrant Health Program Annual Progress Report MG-210 (70).
East Central Michigan Health Service, 319 McCoskry 'Pnfi
Street, Saginaw, Michigan (1970).

Moore, R., The SlaveggWe Rent. New York: Random House

 

 

 

 

 

(1965).
Newby, H., Audiology. New York: Appleton-Century-Crofts
(1964).
Report and Recommendations of the Status of Mlgratory Fa£m_ §;;”
Labor in Michigan. Michigan Civil Rights Commission
(1968).

Reul, M., Where Hannibal Led Up. New York: Vantage Press
(1966).

Robinson, G. C., Anderson, D. 0., Moghadam, H. K., et al.,
A survey of hearing loss in Vancouver school children:
I. Methodology and prevalence. Canadian Medical
Apgociation Journal, 97, 1199—1207 (1967).

Sampson, P., Indian Health Service Modernizes Medical Care
on Reservations. Journal of the American Medical
Association, 218 (4), 511-524 (October 25, 1971).

Sandage, S. M., Child of Hope. New York: A. S. Barnes &
Co. (1968).

Servin, M., The Mexican—American: An Awakening Minority.
Beverly Hills: Glencoe Press (1970).

Shepherd, D. C., Goldstein, R., and Rosenblfit, B., Race
difference in auditory sensitivity. Journal of Speech
and Hearing Research, 7, 389-393 (1964).

Spoerl, D. T., Bilinguality and emotional adjustment.
Journal of Abnormal;Socia1 Psychology, 38, 35-37 (1943).

Studebaker, G. A., Clinical masking of air— and bone—
conduction stimuli. Journal of Speech and Hearing
Disorders, 29 (1), 23-35 (1964).

 

88

Studebaker, G. A., Clinical masking of the nontest ear.
Journal of Speech and Hearing Disordegg, 32 (4),
360—371 (1967).

The Michigan Governor’s Task Force on Migrant Labor.
(October 9, 1969).

The Report of the UNESCO Meeting of Specialists, 1951.
The use of vernacular languages in education. In J. A.
Fishman (Ed.), Readings in the Sociology of Language.
Paris: Mouton (1968).

Thorburn, I. B., Chronic Disease of the Middle Ear Cleft.
In W. G. Scott—Brown (Ed.), Diseases of the Ear, Nose,
and Throat. London: Butterworths & Co. (1965).

Vitalfand Health Statipticg.' Data from the National Health
Survey, National Center for Health Statistics, United
States Department of Health Education and Welfare,
Series 11, No. 102, Washington, D. C. (1970).

 

Whitting, E. G., and Hughson, W., Inherent accuracy of a
series of repeated clinical audiograms. Laryngopcope,
50, 259-269 (1940).

APPENDICES

APPENDIX A

AMBIENT NOISE LEVELS IN TEST ROOM

90

91

.NEU\nogmo «000.0 "on maonwooo Ga mousmmoum ocsomm

.mEmo

pcmumHa.oau um smegma Hosanna map has; :mmaaoaz .xnoaawm um .Hsmd .HH umsmsafl

 

 

oamom 0
ca can so panamaoz
Ho>ma HHMIH0>O
oav mm 50 000m
0Hv mm mm 0000
0Hv Hm hm 000m
0dv mm hm 000m
OHV mm 0e 000A
ma, mm 0v 00m
0H mm 0m 0mm
NN Hm 0v mud
mo cw Boon mp cw onmvcmum mo Ca wumcgmum Nu cw hososv
uwmu moaned Hm>ma ngoflumguoucH «00H :mofluoad Hmma Eoum loum Hmugoo
madmmonm ogsom venomoum mau Eoum Chou DanumEOflosm cgmm o>muoo

anon Ownuofiowosm
o>onm mgwxmmfi on
How ousmmonm canon

odnmzoaam Esfiwxmz

o>onm mgfixwme o:
How whammonm wagon
manmonHm Eszxmz

 

 

.maflummu UflHHOEOMGDm
How poms Boon pmmp may cw ~mao>0a Queen 0:» mo H>0>Hdm Hmowumsoo¢ .H 4 magma

 

APPENDIX B

PACKET OF FORMS USED TO RECORD TOTAL DATA
FOR EACH SUBJECT

92

 

93

 

 

 

QUESTIONARIO
Nombre
Name
Edad Fecha
Age Date

Entrevistado por

 

Questioned by

Estas preguntas seran dirigidas a adultos y a los padres de
los nifibs que serviran en este estudio.

These questions will be posed to the adult subjects and to
the parents of the children who will serve as subjects.

1.

2.

Hay alguna deficiencia en el oir en la familia?
Is there any hearing loss in the family?

Ud. (o su niho) padecen de los oidos?
Do you (does your child) have a hearing loss?

Si padecen, que es lo que se sienten?
If so, describe the loss.

a. Qual oido tiene e1 problema?
Which ear has the prdblem?

b. Siente algfin sonido en los oidos?
Is there any ringing in the ears?

c. Des de cuando padece de los oidos?
Duration of loss?

I
Ud. (o su nifio) tiene catarro frequentemente? (5 o 6
catarros en el afio)
Do you (does your child) have frequent colds (5 or 6
colds per year)?

Le ha chequeado e1 doctor a Ud. (o a su nifio) alguna vez
los oidos?
Has a doctor ever looked into your (your child's) ears?

Ha tenido Ud. (su nifio) algun~problems con los oidos?
Has there ever been any problem with your (your child's)
ears?

a. Ha tenido liquido en los oidos?
Has any liquid run out of the ears?

10.

ll.

94

b. Ha tenido dolor de oidos?
Have there been any earaches?

c. Ha usado medicina para la infeccion de los oidos?
Has any medication been taken for an ear infection?

Ud. (su nifio) tiene problema oyendo hablar?
Do you (does your child) have trouble hearing speech?

a. cuando when
b. describe el problema describe the problem E“”‘
Ud. (su nifio) ha trabajado cerca de maquinaria de

agricultura?
Have you (has your child) worked around farm machinery?

" 7' . '..-‘ ‘1'

a. cuando tienpo? how often?

b. describa las condiciones describe the conditions

 

Ha manejado Ud. alguna vez la maquinaria de agriculture?
Have you ever driven the farm machinery?

a. que tiempo? how often?

b. Ha usado tapones en los oidos mientras trabajaba
alrededor de la maquinaria?
Did you wear ear plugs while working around the
machinery?

Ha tenido Ud. (0 en nifio) alguna vez un examen de los
oidos para diferenciar tonos de sonidos con telefonos?
Have you (has your child) ever had a hearing test where
it was necessary to listen for tones through earphones?

Ha Ud. (o su nifio) usado alguna vez un aparato para los
oidos?
Have you (has your child) ever worn a hearing aid?

 

95

Figure B 1. PHYSICAL EXAMINATION

Subject's Name
Age Date

Physician

 

EARS (Circle one for each ear)

Rt.

UlnwaD-‘O

Lt.

O

UluhUJNH

\DL'DQO‘

10
11

Normal

Obstructed

Retracted Drum

Thickened Drum

Thickened and Retracted Drum

Inflamed middle ear (including secretory otitis
media)

Dry perforation
Perforation with discharge
Acute Otitis Media
Chronic Otitis Media
Congenital Atresia
External Otitis

NOSE (Circle one for eachgside)

Rt.

0

\xmmwaI-a

Lt.

O

\JOWUluhwwl-l

Normal

Septal obstruction

Mucous membrane thickening
Purulent discharge

Acute rhinitis (watery discharge)
Polyps

Allergic rhinitis

Purulent discharge and polyps

continued

I

I

96

NECK GLANDS (Circle one)

0
1
2

Not palpably abnormal
Palpable but not markedly enlarged
Moderate to severe enlargement

TEETH AND MOUTH

0

Ul-prH

Normal

Adentia

Dental caries: Slight

Dental caries: Severe

Severe gingivitis with dental caries
Severe gingivitis without caries

TONSlLS (Circle one)

0

\Jch U1ub halo pa

Normal

Cleanly removed

Tags, not infected

Tags, infected

Hypertrophied

Acute infection

Scarring and retraction moderate
Signs of severe chronic infection

PHARYNXALCircleiongL (Larynx, if significant note on next page)

0

1
2
3

Normal

Acute granular pharyngitis

Chronic lymphoid hyperplasia
Chronic severe lymphoid hyperplasia

97

Subject's Name

 

Age Date

 

Otolaryngologist Y. P. Kapur

Physical Examination Impressions:

HEARING THRESHOLD LEVEL IN dB

Figure B 2. AUDIOGRAM

ISO (1964)

98

Subject's Name

 

Age Date

Audiometrist: Beverly Goldstein

 

 

-20

 

-1O

 

O

 

'10

 

20

 

Lao

 

.40

ISO P/T Average

 

50

(3 frequency)
Right

 

'60

Left

 

_7o

 

80

 

9O

 

100

 

 

 

 

 

 

110

 

 

 

 

 

 

250 500 1000 2000 400%0008000
Frequency (Hz)

KEY TO AUDIOGRAM
Air

Masked Bone Masked

 

Right IRed I 0
Left [Blue | )(

 

 

t: ‘3

 

 

 

APPENDIX C

COMPARATIVE DATA OF AUDIOMETRIC NORMS
AND EARPHONES

99

“'1

 

l“‘l. .

100

Table C 1. Sound pressure values in decibels re: 0.0002
microbar for each frequency classified by norms
and type of earphone according to data pre-
sented by Davis and Krantz (1964) and Cox and
Bilger (1960).

 

 

 

 

 

 

 

Frequency (Hz) ASA 1951 ISO 1964 Differences
Reference Threshold Levelp: WE 705 A earphone r-
125 54.5 dB 45.5 dB 9 dB
250 39.5 24.5 15
500 25 ll 14
1000 16.5 6.5 10
1500 (16.5) 6.5 (10)
2000 17 8.5 8.5
3000 (16) 7.5 (8.5)
4000 15 9 6 .MI
6000 (17.5) 8 (9.5)
8000 21 9.5 11.5

Reference Threshold Levels: TDH 39 wlth a MX- lgARcuflfion

125 51.8 42.8 9

250 39.5 24.5 15

500 24.1 10.1 14
+1000 17.2 7.2 10
2000 18.0 9.5 8.5
4000 14.3 8.3 6
6000 19.5 10 (9.5)
8000 26.8 15.3 11.5

 

Note:

The figures in parentheses are interpolations.

101

Table C 2. The sound pressure level difference in decibels
for each frequency between the Western Electric
705 A earphone and the Telephonics TDH 39 ear-
phone housed in the MX 4l/AR cushion (Cox and

Bilger, 1960).

 

 

Frequency in Hz Difference in Sound Pressure

 

125 2.7 dB

250 0

500 0.9
1000 +0.7
1500 +1.5
2000 +1.0
3000 0.4
4000 0.7
6000 +2.0
8000 +5.8

 

+ Indicates that the sound pressure value is higher by the

listed amount for the TDH 39 earphone.

Where no + sign

is listed, the amount given is then greater for the WE

705 A.

APPENDIX D

CORSO (1963) MEAN AIR-CONDUCTION THRESHOLDS
IN SOUND PRESSURE LEVEL

102

 

PM“

103

Table D 1. Mean air-conduction hearing threshold levels in
dB re: 0.0002 microbar for right and left ears
and male and female combined for adults ages

18-49 years of age, Corso (1963).

 

 

 

 

 

 

 

Frequency (Hz) Threshold Frequency (Hz) Threshold
Ages 18-24 Ages 26-32
250 26.1 250 26.2
500 11.0 500 13.5
1000 5.8 1000 7.2
2000 6.8 2000 7.9
4000 12.2 4000 14.9
6000 25.8 6000 30.7‘
8000 23.7 8000 30.3
Ages 34-40 Ages 43-49
250 26.0 250 26.8
500 12.6 500 11.7
1000 9.4 1000 9.3
2000 10.2 2000 14.5
4000 18.6 4000 26.7
6000 33.8 6000 40.2
8000 32.7 8000 34.0

 

 

APPENDIX E

RAW DATA OF AIR-CONDUCTION THRESHOLDS
FOR CHILDREN AND ADULTS

104

105

Air—conduction threshold levels in this appendix are
listed for all subjects, both Children and adults, in
chronological order by age and separate ears. By referring
to Tables 5 and 8, it is possible to determine the age of
all subjects listed only by threshold in this appendix.
For example, it is listed in Table 5 that two children at
age five and six at age six were tested audiometrically.
The first two thresholds in Tables E 1 and E 2 are the
thresholds for the five year olds and the next six thres-
holds are thresholds for the six year olds. This same
method can be used along with Table 8 to determine the age
of the adult subjects listed only by threshold in Tables

E 3 and E 4.

 

106

 

 

 

Table E 1. Air-conduction threshold levels in dB for the
right ear for all children ages 5-16-years re:

ISO (1964)
250 (Hz) 500 1000 2000 4000 6000 8000
+ 15 10 15 15 15 20 35
0 15 10 5 10 5 10 - 5
0 25 20 5 25 30 25 20
0 5 5 - 5 5 5 0 5
0 10 10 0 - 5 5 5 10
+ 25 15 25 10 10 10 15
+ 15 10 5 5 20 25 45
+ 20 15 20 20 25 25 30
-- 15 10 0 10 10 20 25
0 20 25 25 25 35 35 25
0 15 5 0 0 15 10 0
+- 15 15 15 15 20 35 25
+ 20 15 10 0 5 25 20
- 10 10 5 10 25 25 30
0 10 0 - 5 5 5 0 - 5
- 20 10 0 5 15 5 10
+- 25 15 10 15 15 20 15
- 15 15 5 0 5 10 10
+ 10 5 0 - 5 10 5 - 5
-+ 10 10 15 10 5 10 20
- 10 15 0 0 15 - 5 - 5
0 5 5 - 5 0 5 15 5
+- 10 5 0 10 20 5 5
+ 30 25 25 20 25 40 35
- 5 5 5 10 5 15 15
-+ 15 10 5 5 15 10 0
- 10 5 0 10 5 5 5
0 20 15 5 15 15 30 25
0 30 25 20 20 20 20 35
0 20 10 5 0 15 5 0
+ 30 25 20 20 30 20 25
+ 25 20 0 0 10 10 25
- 20 15 5 5 15 20 10
-+ 10 10 10 5 20 15 25
- 20 15 10 10 10 15 5
-+ 10 15 15 10 10 5 5
0 5 5 0 5 15 25 15

 

+positive ENT finding

“negative ENT finding

0

no ENT examination

Far-.1

 

F"L"

107

Table E 2. Air—conduction threshold levels in dB for the
left ear for all children ages 5-16 years re:

 

 

 

ISO (1964)

250 (Hz) 500 1000 2000 4000 6000 8000
+ 5 15 15 10 25 25 20
0 20 15 5 10 5 5 10
0 15 10 0 15 20 15 5
0 5 5 0 5 15 0 0
0 10 15 5 5 25 20 5
+ 35 35 30 30 35 50 45
+- 10 5 15 25 20 25 15
+- 15 15 15 15 15 15 5
- 20 15 10 5 5 — 5 10
0 40 15 25 40 45 25 20
0 .10 5 5 5 10 15 10
+ 40 55 55 50 55 55 40
-+ 10 10 10 5 15 15 15
- 5 5 10 5 20 20 10
0 5 10 - 5 5 0 -10 0
— 15 15 0 5 0 0 10
+ 35 20 15 15 20 30 25
- 5 5 10 0 10 5 10
+ 5 0 - 5 0 15 10 - 5
+- 0 10 15 15 10 0 0
- 15 10 0 5 15 10 10
0 15 15 0 5 20 25 20
+— 10 10 10 15 10 0 - 5
+ 35 35 30 30 30 30 35
- 10 5 0 0 5 5 15
+- 15 15 10 5 15 15 5
— 5 0 5 0 5 5 10
0 10 5 5 0 0 10 10
0 30 30 30 30 25 30 25
0 5 5 0 0 5 20 0
+ 20 25 30 40 45 45 40
+ 5 5 5 - 5 10 0 25
- 20 15 15 15 20 25 20
+ 20 20 15 15 30 20 20
- 15 5 5 0 5 10 10
+ 5 10 15 15 5 15 5
0 0 5 5 5 10 10 10

 

+positive ENT finding

-negative ENT finding

Ono ENT examination

 

 

 

108

Table E 3. Air-conduction threshold levels in dB for the
right ear for all adults ages 18-50 years re:
ISO (1964).

 

 

250 (Hz) 500 1000 2000 4000 6000 8000

 

- 10 15 5 10 15 0 5
-+ 25 20 10 10 10 5 5
0 10 10 10 5 5 5 5 18-24
+ 20 15 — 5 - 5 5 10 — 5 years
+ 30 25 10 15 25 55 35
- 10 10 15 15 15 15 20
-+ 20 15 5 I- 5 5 15 15
4- 10 S 0 - 5 5 15 15
0 15 10 0 5 5 5 5
0 10 5 0 5 10 15 5
-+ 20 15 5 5 10 15 15
+ 5 0 - 5 - 5 5 5 10 25-32
+ 25 20 15 15 20 25 25 years
0 10 15 S 5 15 15 15
-+ 10 10 10 5 15 15 25
+ 45 45 35 25 35 45 55
-+ 15 0 0 5 10 10 0
+ 10 10 5 10 20 25 15 33—40
0 25 35 10 25 60 55 40 years
+ 20 20 20 20 45 40 25
0 5 5 5 0 5 10 0
o 10 5 5 5 15 15 0 43‘5°
0 15 10 10 5 15 25 15 Years

 

I"

 

+positive ENT finding

_negative ENT finding

0no ENT examination

109

Table E 4. Air-conduction thrashold levels in dB for the
left ear for all adults ages 18—50 years re:
ISO (1964).

250 (Hz) 500 1000 2000 4000 6000 8000

 

- .15 1o 5 5 15 o o
.+ 15 10 5 10 5 10 5
o 20 15 5 1o 15 20 25 18-24
+ 10 10 - 5 - 5 15 10 15 years
+ 5 - 5 5 1o 15 35 4o
- 1o 10 15 1o 15 20 25
+- »15 15 o o o 10 15
-+ W15 10 o o o 15 30
o 30 15 20 20 25 15 20
o 15 5 o 10 10 25 - 5
+- 15 15 5 1o 15 15 ' 30
+ s 5 o 5 5 15 0 25-32
+ 20 20 15 1o 20 15 25 years
0 10 o - 5 - 5 o 5 o
+ 10 5 5 o 15 30 35
+ 35 25 15 5 15 20 40
+ 10 5 5 15 35 55 so 33_40
+ 15 5 s 20 25 35 40
o 10 10 15 25 60 55 45 Years
+ 20 20 20 1o 25 15 20
o 5 5 5 5 10 25 - 5
o 10 5 0 1o 5 15 15 43'5°
0 15 10 15 20 30 25 15 Years

 

{FIT' -_- .-

 

+positive ENT finding
-negative ENT finding

0 O 0
-no ENT examination

APPENDIX F

RAW DATA OF AIR-BONE GAPS FOR

CHILDREN AND ADULTS

110

Im

 

111

The air-bone gaps for both children and adults are
listed in this appendix by separate ears. These air—bone
gaps are presented in chronological order of age and
correspond directly to the air-conduction thresholds of
Appendix E. To obtain the air-bone gap of any threshold
in Appendix E, all that is necessary is to find the cor-

responding line for the correct ear and correct age group.

a ill.-.’v—vfl x .1

 

112

Table F l. Air-bone gaps in dB for each frequency for the
right ear on all children ages 5-16 years.

 

 

 

 

500 (HZ) 1000 2000 4000
15 15 10 5
5 0 5 0
10 0 15 25
15 0 5 20
0 0 0 10
10 30 0 0
10 0 0 5
10 15 15 10
10 0 5 10
30 25 15 40
0 0 0 15
0 5 0 5
10 5 0 0
10 0 0 15
5 0 O 0
15 0 0 5
0 0 0 0
20 0 0 5
5 0 0 10
0 5 0 0
10 0 0 10
0 0 0 5
0 0 0 0
0 0 10 0
0 10 10 5
5 0 0 0
5 0 0 0
10 0 10 15
5 5 0 5
5 0 0 10
10 0 5 15
15 O 5 5
5 0 0 0
0 0 0 5
10 0 0 5
10 10 5 10
5 0 0 10

 

113

Table F 2. Air-bone gaps in dB for each frequency for the
- left ear on all children ages 5—16 years.

 

 

500 (Hz) 1000 2000 4000

 

H

w NNN
U H
O UT U1

g...
an
n+-
00

NH

0:
OOOU’IOOOOU‘IOOOOOOOOOOOOOWUIO
OOOU'lOU'IOOUlOOOOOU'IU'IOOU‘IU'IOOUI

N

[.1
O 0
Hr-
OOOU‘IOOU‘IOU'ILHOOOOOOOOOU‘IOOOU'IOOOU'IU'IOU'IOOU'IOOO

P' ham

 

114

Table F 3. Air-bone gaps in dB for each frequency for the
right ear for all adults ages 18-50 years.

 

 

 

500 (Hz) 1000 2000 4000
15 5 15 15
0 5 0 5
10 5 0 0
5 0 0 0 18-24
25 10 10 15 years
5 O 10 10
15 0 0 10
10 0 0 0
O 0 0 0
10 0 0 10
10 0 0 0
10 0 0 10 25-32
5 0 0 0 years
0 0 0 0
0 0 0 0
0 0 0 15
5 0 0 0 years
0 0 0 0
0 0 0 15
5 0 5 0
0 0 0 0 years

 

 

‘+_

115

Table F 4. Air-bone gaps in dB for each frequency for the
left ear for all adults ages 18-50 years.

 

 

 

 

500 (Hz) 1000 2000 4000
20 5 5 0
10 0 0 0
15 5 0 10 w“
5 o 20 15 18-24 5
0 5 5 10 years ;
15 5 5 10 4
10 0 0 0 ;
15 0 0 0
0 15 30 20 u
5 5 5 5 {
15 0 0 0 a“
15 5 O 0 25-32
10 0 0 0 years
0 0 5 0
0 0 0 0
0 0 0 0
5 0 15 10
O 0 5 0 33-40
0 0 0 0 years
0 0 0 0
0 0 0 0
5 1o 5 10 Years

 

MICHIGAN STATE UNIV. LIBRARIES

I III III Illlllll
1 4

10 4918

312930