J Am Acad Audiol 12 : 64-79 (2001)
Technology, Expectations, and
Adjustment to Hearing Loss :
Predictors of Hearing Aid Outcome
J. Christopher K. Jerram*
Suzanne C. Purdy*t
Abstract
This study examined the influence of technology, demographic factors, and prefitting expectations, attitudes, and adjustment to hearing loss on hearing aid outcome . Clients obtaining
new hearing aids completed questionnaires measuring personal adjustment to hearing loss,
expectations of and attitudes toward hearing aids, and hearing aid benefit. Eighty-one percent of the 200 subjects completing the prefitting questionnaires returned questionnaires
evaluating hearing aid outcome. Factors affecting hearing aid use, overall satisfaction, and
benefit were investigated using regression analyses . Higher use time was associated with
higher prefitting expectations and greater acceptance of hearing loss . Greater benefit in easy
and difficult listening situations was predicted by higher prefitting expectations . Multiplememory hearing aids produced higher satisfaction . Benefit was greater for multiple-memory,
multiple-channel, and wide dynamic range compression aids . Findings were consistent with
previous studies showing positive outcomes for newer technologies but also showed that two
subjective factors, prefitting hearing aid expectations and acceptance of hearing loss, significantly influenced hearing aid outcome.
Key Words: Attitude, benefit, expectations, hearing aid, hearing aid use, personal adjustment, questionnaire, satisfaction, technology
Abbreviations: APHAB = Abbreviated Profile of Hearing Aid Benefit, BTE = behind the ear,
CIC = completely in the canal, CPHI = Communication Profile for the Hearing Impaired, HAPI
= Hearing Aid Performance Inventory, HARQ = Hearing Attitudes in Rehabilitation Questionnaire,
HHIE = Hearing Handicap Inventory for the Elderly, HPI = Hearing Performance Inventory,
ITC = in the canal, ITE = in the ear, MAPHAB = Modified Abbreviated Profile of Hearing Aid
Benefit, MELLI = multiple environmental listening utility, MPAS = Modified Personal Adjustment
Scale, PHAB = Profile of Hearing Aid Benefit, SADL = Satisfaction with Amplification in Daily
Living, WDRC = wide dynamic range compression
vaiiety of measures have been developed
to assess hearing aid outcome including
A aided performance and benefit, satisfaction with hearing aids, and amount of hearing aid use (Brooks, 1990 ; Dillon et al, 1999 ;
Humes, 1999). Hearing aid benefit can be defined
as an increase in hearing ability after provision
of an aid. Objective benefit measures do not
require the wearer to express an opinion or
*Audiology Section, Department of Physiology, The
University of Auckland, Auckland, New Zealand ; tNational
Acoustic Laboratories, Sydney, Australia
Reprint requests : Chris Jerram, Audiology Section,
Department of Physiology, The University of Auckland,
Faculty of Medicine and Health Sciences Private Bag 92019,
Auckland, New Zealand
64
judgment regarding the hearing aids . There are
many objective speech recognition tests that
can be used to assess benefit (Levitt and Resnick,
1978) and purely acoustic tests of hearing aid
function in a coupler or on the person's ear (Wetzell and Harford, 1983 ; Mueller, 1992). Subjective measures of benefit require a judgment or
opinion, such as loudness or quality judgments
using rating scales (e .g ., Arlinger and Billermark, 1999 ; Jenstad et al, 1999).
Subjective hearing aid benefit also has been
measured as reduction in perceived disability or
handicap (Weinstein, 1990). The International
Classification of Impairments, Disabilities, and
Handicaps developed in 1980 by the World
Health Organization defines disability as the
degree to which a physical impairment causes
Predictors of Hearing Aid Outcome/Jerram and Purdy
dysfunction and handicap as the psychosocial
sequelae of this (Badley and Lee, 1987a, b ;
Badley et al, 1987 ; Arnold and MacKenzie, 1998).
Many different self-assessment scales have been
developed to measure hearing disability and
handicap (Noble, 1998), including the Profile of
Hearing Aid Benefit (PHAB, Cox et al, 1991) and
the Hearing Handicap Inventory for the Elderly
(HHIE, Ventry and Weinstein, 1982), which
have been used extensively to measure hearing
aid benefit in the realms of disability (PHAB) and
handicap (HHIE) .
Humes (1999) identified several components
of hearing aid outcome including aided performance measured by speech recognition scores
and the HHIE, hearing aid use time, loudness
and sound quality ratings, and satisfaction . Satisfaction is an internalized construct that can be
measured as a single global measure (Brooks,
1985 ; Kuk and Pape, 1993 ; Dillon et al, 1999) or
as separate components (Kochkin, 1993, 1995 ;
Cox and Alexander, 1999) . Although overall satisfaction is related to benefit, satisfaction and
benefit are separate dimensions of hearing aid
success (Kochkin, 1995 ; Purdy and Jerram,
1998 ; Humes, 1999) .
The psychosocial effects of hearing aids have
also been studied . Mulrow et al (1990) reported
improved cognitive function and reduced depression in clients fitted with hearing aids compared
with a control group of waiting list clients .
Bridges and Bentler (1998) found higher ratings
of life satisfaction in successful hearing aid
wearers . Garstecki and Erler (1998) found fewer
depressive tendencies among hearing aid wearers than hearing aid nonwearers, and Crandell
(1998) found that hearing aids have a positive
impact on functional health status in elderly
listeners . In a recent large study of hearingimpaired listeners and their family and friends,
Kochkin and Rogin (2000) reported many positive effects of hearing aids on quality of life .
Predicting Hearing Aid Outcome
Many variables have been investigated as
possible predictors of success with hearing aids .
For example, Mulrow et al (1992) found that
greater baseline perceived handicap, younger
age, lower education level, greater degree of
high-frequency hearing aid gain, better near
visual acuity, and fewer number of medications
all positively influenced hearing aid outcome .
The present study investigated the effects on
hearing aid outcome of demographic, hearing aid
technology, and subjective predictor variables .
A number of previous studies have examined
these variables.
Age, Hearing Loss, and Gender
Deterioration in central auditory function in
older hearing aid wearers can adversely affect
hearing aid outcome (Kricos et al, 1987 ; Gatehouse, 1990 ; Stach et al, 1991) . General ill
health, loss of mobility, and social isolation
(Welzl-Miiller and Stephan, 1986 ; Stephens and
Meredith, 1991 ; Evenhuis, 1995 ; Cohn, 1999)
also reduce success with hearing aids in elderly
hearing aid wearers . This is consistent with
reports of reduced hearing aid performance with
increasing age (Crowley and Nabelek, 1996 ; Jerram and Purdy, 1997) .
People with greater hearing loss wear their
hearing aids more often (Brooks, 1985 ; Satherley, 1992). The reported relationship between
audiometric thresholds and hearing aid benefit
is variable, ranging from nonsignificant (Schum,
1992) to significant (Kochkin,1995), with greater
benefit usually being associated with greater
loss . As expected, poorer hearing aid performance is associated with worse hearing thresholds (Purdy and Jerram, 1998).
Garstecki and Erler (1998) found differences between the sexes when they compared
hearing aid wearers and nonwearers using the
Communication Profile for the Hearing Impaired
(CPHI) inventory. Significant gender differences
were present for 6 of the 25 CPHI scales (Problem Awareness, Social Communication Importance, Nonverbal strategies, Anger, Stress, and
Denial) . Women were more likely to admit to
communication problems, use nonverbal strategies to remedy difficult communication situations, and report feelings of anger, stress, and
negative emotions than men . Crowley and
Nabelek (1996) found no effect of gender on ratings of hearing aid performance, but Garsteki
and Erler's (1998) results suggest that gender
may affect some hearing aid outcome measures .
Hearing Aid Technology
Choice of monaural or binaural hearing aid
fitting affects outcome, with greater success
found for binaural fittings (Brooks, 1984 ; Day et
al, 1988 ; McKenzie and Rice, 1990), particularly for directional hearing aids (Leeuw and
Dreschler, 1991).
A variety of new hearing aid technologies are
currently available that aim to enhance perception of speech, particularly in background
65
Journal of the American Academy of Audiology/Volume 12, Number 2, February 2001
noise . This includes digital circuitry, multiple
memories, multiple microphones, multiplefrequency channels, and various forms of compression . Kochkin (1996) found that outcomes
were consistently better for newer "highperformance" hearing aids (higher overall satisfaction, perceived improvement in quality of life
and benefit, etc.) . Modern digital hearing aids
generally provide clearer sound than older analog aids (Kates and Weiss, 1996 ; Kiessling, 1996 ;
Arlinger et al, 1998 ; Valente et al, 1998). Multiple-memory hearing aids have proved an effective way of adjusting amplification for specific
listening situations (Keidser, 1995 ; Berninger
and Nordstrom, 1997). Dual-microphone systems result in improved speech perception in
noise (Valente, 1999). Overall satisfaction with
hearing aids is highly related to the number of
listening situations in which wearers' needs are
met (Kochkin, 1996). Kochkin (1996) found that
multiple-memory and multiple-microphone hearing aids, allowing different amplification characteristics in different listening situations,
provide the highest satisfaction.
Channelling of the incoming signal into
more than one frequency band allows independent adjustment according to the degree of hearing loss in that frequency region . Many modern
hearing aids have multiple channels, allowing
compression parameters to vary across frequency. Kochkin (1996) found higher "usage satisfaction" among users of multiple-channel
hearing aids compared with single-channel aids .
It is still not clear whether new nonlinear
compression circuits, in which amplification is
reduced for loud sounds, are better than linear
(equal amplification for loud and soft sounds) for
speech understanding in noise (Byrne, 1996 ;
Verschuure et al, 1996). Dillon (1996) reviewed
the compression literature and concluded that
for speech in quiet at a comfortable level, no compression scheme yet tested offers better intelligibility than individually selected linear
amplification .
Variable results have been found regarding the relative advantages of the four main
hearing aid styles : behind the ear (BTE), in the
ear (ITE), in the canal (ITC), and, recently, completely in the canal (CIC). Smaller ITE and CIC
hearing aids are less associated with the stigma
of hearing loss than the more conspicuous BTE
style (Brooks, 1994) . ITE hearing aids can present handling problems in older hearing aid
users (Meredith and Stephens, 1993) but not consistently (Upfold and May, 1990). The latter
study found no difference in performance
66
between ITC, ITE, and BTE hearing aids in
elderly hearing aid wearers. CIC hearing aids
appeal to younger, less impaired individuals,
but wearers rate CIC hearing aids lower on reliability, ease of adjusting, and performance relative to cost (Kochkin, 1995).
Psychosocial Factors
Several studies have examined the effects
of personality on hearing aid outcome (Gatehouse, 1994 ; Scott et al, 1994 ; Cox et al, 1999).
Cox et al (1999) found that a more outwardlooking personality gained higher benefit in the
Easy Listening, Reverberant, and Background
Noise subscales of the abbreviated version of the
PHAB (APHAB). Gatehouse (1994) found that
depression was associated with less hearing aid
use and lower reports of hearing aid benefit and
satisfaction . Other aspects of personality measured with the Crown-Crisp Experiential Index
were also highly correlated with hearing aid
outcome (Gatehouse, 1994 ; Noble, 1998).
Several studies have examined the influence
of attitudes toward hearing loss and hearing
aids on hearing aid outcomes (Hickson et al,
1986, 1999 ; Brooks, 1989 ; Gatehouse, 1994 ; Hallam and Brooks, 1996). Using the Hearing Attitudes in Rehabilitation Questionnaire (HARQ),
Hallam and Brooks (1998) found that clients
who were least distressed by their hearing difficulties and reported not wanting or needing a
hearing aid used their aids least frequently and
evaluated them less highly in listening situations . Gatehouse (1994) and Hickson et al (1986,
1999) found a significant positive relationship
between attitudes toward hearing aids and their
use.
Personal adjustment to disability also has
been associated with rehabilitation outcome
(Brown and Munford, 1984 ; Corso, 1987 ; Burke
et al, 1988) and is seen as important in offering
guidelines for aural rehabilitation (May, 1986 ;
Stephens, 1996). Crowley and Nabelek (1996)
found that personal adjustment to hearing loss
measured using the CPHI was predictive of hearing aid performance in difficult listening situations
measured using the Profile of Hearing Aid Performance (Cox and Gilmore,1990) . In contrast, Cox
and Rivera (1992) found that CPHI composite
scores were not predictive of PHAB benefit.
Counselling to ensure that hearing aid wearers make informed choices, have realistic expectations, and know how to use hearing aids has
been found to influence hearing aid success in
adults (Brooks and Johnson, 1981 ; McCarthy et
Predictors of Hearing Aid Outcome/Jerram and Purdy
al, 1990 ; Rose and Pool, 1994 ; Kapteyn et al,
1997 ; Kochkin, 1999) . Kricos et al (1991) developed a 48-item expectations checklist and found
that 87 percent of participants had high expectations of hearing aids . Schum (1999) found
that candidates for amplification tend to expect
more benefit than they will typically achieve,
especially when listening to speech in noise or
without visual cues . In contrast, Bentler et al's
(1993) results suggested that performance
exceeded expectations . Schum (1999) concluded
that hearing aid benefit could not be reliably predicted from perceived need or expectation . Brooks
and Johnson (1981) reported that prefitting
counselling had a positive effect on hours of
hearing aid use and satisfaction with hearing
aids, which suggests that realistic expectations
should improve hearing aid outcomes .
The present study was designed to evaluate
which, if any, of a number of the predictor variables discussed above influence three measures
of hearing aid outcome, perceived hearing aid
benefit, overall satisfaction, and daily hours of
hearing aid use .
METHOD
Subjects
A total of 12 private and 7 public hospital
audiology clinics participated in the study. Over
an approximately 18-month period, adult
prospective hearing aid wearers undergoing
their initial hearing aid evaluation were introduced to the study by their audiologist . Consent
forms were received from 225 potential participants . Each was sent questionnaires examining personal adjustment to hearing loss, hearing
aid expectations, attitudes to hearing aids
(Appendix), and unaided hearing ability, to be
completed and mailed to the researcher prior to
fitting of hearing aids . Complete sets of questionnaires were received from 200 individuals
(89% response rate). These 200 individuals
received a copy of the aided version of the Modified APHAB (MAPHAB) and the satisfaction
questionnaire for completion and return approximately 10 weeks after their final hearing aid
follow-up appointment.
Completed aided questionnaires were
received from 162 subjects (81% return rate), 81
males and 81 females. Seventy-six of these subjects (47%) attended public hospital clinics, and
86 (53%) attended private clinics. Ages ranged
from 31 to 88 years (mean = 70 .5 years, SD =10.8).
Twenty-five were fully employed, 13 were partially
employed, and 124 were not employed outside the
home . Sixty-one subjects were new hearing aid
users, and 101(62%) had some prior hearing aid
experience . Figure 1 shows the subjects' mean
right and left ear pure-tone thresholds in the frequency range of 0 .5 to 4 kHz . All had sensorineural
hearing loss .
Outcome Measures
Hearing aid outcome was measured in three
ways : daily hearing aid use time, hearing aid
benefit, and overall satisfaction . Overall hearing aid satisfaction was measured using a single 20-point rating scale ranging from "very,
very dissatisfied" (1) to "very, very satisfied"
(20) . Subjects were asked to indicate the amount
of hearing aid use (0-1, 1-4, 4+ hours per day) .
Hearing aid benefit was measured using a modified version of the APHAB questionnaire (Cox
and Alexander, 1995), which evaluates unaided
and aided hearing performance in 24 listening
situations . Hearing aid benefit is measured as
the difference in hearing performance with and
without a hearing aid. A positive difference in
scores between unaided and aided versions indicates that hearing aids are beneficial . The
APHAB measures benefit in four types of listening environment : Ease of Communication,
Reverberation, Background Noise, and Aversiveness of Sounds . Factor analysis of the aided
version of the APHAB for New Zealand listen-
-10
10
30
50
70
90
110
0 .5
1
2
4
Frequency (kHz)
Figure 1 Mean left and right ear audiometric thresholds (dB HLl of the 162 subjects completing the study.
Error bars show standard deviations .
67
Journal of the American Academy of Audiology/Volume 12, Number 2, February 2001
ers (Purdy and Jerram, 1998) revealed three
factors that roughly matched the four scales of
Cox and Alexander (1995) . These factors represent easy and difficult listening situations and
listening to aversive environmental sounds .
Purdy and Jerram (1998) dropped two items
from the questionnaire due to poor response
rates. The resulting 22-item questionnaire, the
MAPHAB, was used in the present study as a
measure of hearing aid outcome. The APHAB
response scale was altered from the original to
be an equal-interval scale (Keller et al, 1998),
with a scale ranging from never (0%) to always
(100%) with 10 percent increments marked on
the scale.
Client and Hearing
Aid Predictor Variables
For subjects who completed the study, clinicians provided information on subject age;
pure-tone hearing thresholds at 0.5, 1, 2, and
4 kHz ; type of hearing loss ; monaural or binaural fitting, hearing aid style; and type of
hearing aid technology (peak clipping, output,
input, and wide dynamic range compression
[WDRC] ; multiple microphone ; multiple memory; multiple channel). When they completed the
final hearing aid questionnaires, subjects were
asked to indicate the duration of hearing aid
experience (<6 weeks, 6 weeks-11 months, >1
year) and employment status (full time, part
time, not employed outside the home).
The adjustment factor of the CPHI, consisting of 100 items comprising 13 of the 25 original CPHI subscales (Demorest and Erdman,
1986, 1987, 1989), has been used to measure personal adjustment to hearing loss in a range of
domains (Crowley and Nabelek, 1996 ; Erdman
and Demorest, 1998 ; Jerram and Purdy, 1999).
Jerram and Purdy (1999) obtained high (> 0.8)
alpha internal consistency values (Cronbach,
1951) for New Zealand listeners with hearing
impairment for 7 of the 13 adjustment factor subscales . Three of the adjustment subscales with
high internal consistency (Jerram and Purdy,
1999), Acceptance of Loss, Stress, and Denial,
were used to assess personal adjustment to
hearing loss in the present study. The 25-item
questionnaire containing the three adjustment
subscales was called the Modified Personal
Adjustment Scale (MPAS) .
Items in the Acceptance of Loss and Stress
subscales are negatively worded, with a 5-point
rating scale ranging from "strongly disagree"
(1) to "strongly agree" (5). Ahigh score indicates
68
poor personal adjustment in coping with the
statement described. According to the analysis
procedure of Demorest and Erdman (1987),
scores are reversed, and after reversal, a high
score is indicative of a good level of personal
adjustment . For items in the Denial subscale, a
low score indicates denial of a negatively worded
statement. Persistent disagreement with common emotional reactions experienced by listeners with hearing impairment represents an
unwillingness to admit that a problem existsthus, a poor personal adjustment to the problem.
Items in the Denial subscale are therefore not
reversed to keep scoring for this subscale parallel to that of the other subscales.
Prefitting attitudes toward hearing aids
were measured using the factor 1 ("hearing aid
stigma") items in the hearing aid section of the
HARQ (Hallam and Brooks, 1996). The HARQ
subscale consists of eight negatively worded
items (e .g ., "It would make me feel old to wear
a hearing aid") and one positively worded item
(item 9, "I think the BTE hearing aids are really
quite small and inconspicuous") . Scoring ranges
from "true" (1) to "not true" (3). Scoring is
reversed for item 9; thus, a high score represents
a positive attitude toward hearing aids .
Prefitting hearing aid expectations were
measured using the expectations questionnaire
developed by Seyfried (1990) . Seyfried's questionnaire contains 12 items, 7 of which are positively worded (e .g ., "My hearing aids will fit
comfortably") and 5 of which are negatively
worded (e .g ., "I will adjust slowly to my hearing
aids") . Scoring ranges from "strongly agree"
(1) to "strongly disagree" (6) for all items . For
analysis, scoring is reversed for the negatively
worded items so that a low score represents
high expectations .
RESULTS
Hearing Aid Characteristics
Ninety-five subjects (59%) were binaurally
fitted, and 67 (41%) were monaurally fitted .
Figure 2 shows numbers of subjects wearing
hearing aids with each of the hearing aid technologies that were examined as predictors of
outcome. The most widely prescribed technology
was WDRC . Very few subjects wore linear peakclipping hearing aids . Multiple-memory and
multiple-frequency channel aids were prescribed
more often than multiple-microphone aids .
Predictors of Hearing Aid Outcome/Jerram and Purdy
items in the expectations questionnaire had
very poor item-total correlations (9, 11, and 12)
and were not included in subsequent analyses .
With these three items excluded, Cronbach's
alpha was 0 .60 for the expectations questionnaire
(n = 171) . Bentler et al (1993) analyzed subsets
of Seyfried's (1990) expectations questions and
derived a subset of five items yielding a higher
alpha value (0 .74) . This subset resulted in a
poor alpha value (0 .45) in the present study,
lower than that obtained when all 12 items were
included (0 .49) .
WDRC
63
0
Other C
P-clip
U
U
E~
b
a
.Cd
`0
x
M-band
M-mem
M-mic
0
20
40
60
80
100
Subjects Using Technology
Figure 2 Numbers of subjects using each type of
hearing aid technology : wide dynamic range compression (WDRC), other types of input or output compression (Other C), peak clipping (P-Clip), multiple channels
(M-band), multiple memories (M-mem), and multiple
microphones (M-mic) . These results are based on the
audiologists' reports for the 162 subjects who returned
the aided questionnaires .
Item Analysis of
Prefitting Questionnaires
Item analyses were performed to determine
internal reliability of the personal adjustment,
expectations, and hearing aid attitudes questionnaires completed by the 200 subjects who
responded to the first mail-out . Only questionnaires with no missing values were included in
the analysis . Reliability was excellent (Cronbach's alpha = 0 .90-0 .92) for the WAS personal adjustment subscales, Acceptance of Loss
(n = 153), Stress (n = 152), and Denial (n = 144) .
Item 9 of the HARQ attitudes scale was poorly
correlated with the other items in the questionnaire. Cronbach's alpha for the HARQ,
excluding item 9, was 0 .81 (n = 189) . Three
Results for Subjects Completing
Aided Questionnaires
Table 1 shows means and standard deviations for the MPAS subscales and the HARQ and
expectations prefitting questionnaires for the
162 subjects completing the study, after omission
of item 9 from the HARQ and items 9, 11, and
12 from the expectations questionnaire. Only 135
subjects (83%) completed all items for the expectations questionnaire, so an expectations score
was calculated for the 97 percent of subjects
who completed at least 7 of the 9 questions. For
the MPAS subscales and the HARQ questionnaire, most subjects (89-94%) responded to
every item ; thus, analyses were based on subjects who responded to all items.
For analysis of the expectations questionnaire, scoring is reversed for the negatively
worded items so that a low score represents
high expectations . The mean expectations score
of 2.3 of a maximum of 6 indicates that, on average, subjects had positive expectations of hearing aids . For the HARQ questionnaire, a high
score represents a positive attitude toward hearing aid use. HARQ scores indicated a range of
attitudes to hearing aids from negative to positive, with the mean score in the middle of the
3-point scale. A high WAS score indicates a
Table 1 Means, SDs, Range, and Number of Subjects for the WAS Personal Adjustment Subscales
(Acceptance of Loss, Stress, Denial) and the HARQ Attitudes* and Expectationst Questionnaires .
Acceptance (15)
Stress (15)
Denial (15)
Attitude (13)
Expectations (16)
Mean
3 .65
3 .19
2.61
1 .36
2 .30
Range
1 .22-4 .20
1 .00-5 .00
1 .00-5 .00
1 .00-2 .75
1 .49-4 .16
SD
N
1 .31
155
1 .23
155
1 .23
143
0.32
157
0.56
157
*Excluding item 9, 'excluding items 9, 11, and 12,
indicate good
Data are shown for subjects completing all WAS and HARQ items and at least seven expectations items. High values
maximum
personal adjustment (Acceptance, Stress, Denial), a positive attitude (HARQ) toward hearing aids, and low expectations . The
rating is shown in parentheses for each scale.
69
Journal of the American Academy of Audiology/Volume 12, Number 2, February 2001
high level of personal adjustment . The WAS
mean data showed a moderately high acceptance of hearing loss and adjustment to stress
related to hearing loss and a moderate level of
awareness of communication problems .
Only two subjects wore their aids 1 hour or
less per day, 48 (26%) wore their aids 1 to 4 hours,
and 112 (69%) wore their aids 4+ hours per day.
For the 162 subjects completing the study, ratings of overall hearing aid satisfaction ranged
from 2 to 20 . Only 5 subjects had satisfaction
scores below 10 . Mean satisfaction was 15 .33
(SD = 3.33) or 77 percent of the entire scale.
Thus, on average, people were very satisfied
with their hearing aids .
Only 58 percent of subjects completed all of
the unaided and aided MAPHAB items . Ninety
percent of subjects (n = 146) completed at least
80 percent of the MAPHAB items (i .e ., >_17 of 22).
For these subjects, item 16 ("The sounds of construction work are uncomfortably loud") had
the poorest response rate (78%) of the individual items. Response rates for the other individual MAPHAB items ranged from 92 to 100
percent. Means and standard deviations for
MAPHAB benefit scores are shown in Table 2 for
subjects who responded to at least 80 percent of
the MAPHAB items. On average, benefit scores
were slightly higher for the difficult listening
than for the easy listening factor and were lowest for the aversiveness of sounds factor.
Relationships between
Outcome Measures
The relationship between the satisfaction
and benefit outcome measures was investigated
by calculating Pearson correlation coefficients for
the 146 subjects completing at least 80 percent
of the MAPHAB items. Satisfaction was correlated with factors 1 (r = .224, p = .007) and 2
(r = .312, p < .001) but not factor 3 (r = .072, p
= .387) benefit scores . The strongest relationship
between satisfaction and benefit scores was for
difficult listening situations (factor 2) . Figure 3
Satis
F1
F2
F3
Figure 3 Mean satisfaction rating and MPHAB factors
1, 2, and 3 scores for subjects wearing their hearing aids
<4 hours (n = 51) and 4+ hours (n = 111) . Error bars show
standard errors .
shows satisfaction ratings and MAPHAB benefit as a function of hearing aid use time . On
average, subjects who wore their aids more had
higher satisfaction ratings and higher factors 1
and 2 MAPHAB benefit scores .
Effects of Predictor Variables
on Outcome Measures
Ordinal logistic regression analyses were
used to investigate whether demographic, hearing aid technology, or subjective factors had an
effect on hours of hearing aid use, satisfaction,
and benefit. Factors that were investigated
included age, gender, employment status, type
of clinic (public vs private), prior hearing aid
experience, four-frequency pure-tone average
(combined and separate ears), monaural versus binaural fitting, hearing aid style (BTE,
ITE, ITC, CIC), hearing aid input-output characteristic (WDRC, input compression, output
limiting compression, peak clipping), "highperformance" hearing aid features (multiple
channel, multiple memory, multiple microphone),
Table 2 Means, SDs, and Range for the Satisfaction Ratings (Using a 20-Point Scale) and
MAPHAB Factors 1 (Easy Listening), 2 (Difficult Listening), and 3 (Aversive Sounds)
Satisfaction
Mean
SD
Range
15 .33
3 .33
2-20
Factor 1
24 .4
24 .1
-45 .2-81 .8
Factor 2
Factor 3
25 .3
18 .5
-21 .1-82 .5
-5 .1
24 .5
-71 .5-76 .3
Percent hearing benefit is shown for MAPHAB factors 1 to 3 . Data are shown for the subjects who completed at least 80% of the
MAPHAB unaided and aided items (n = 146) .
70
Predictors of Hearing Aid Outcome/Jerram and Purdy
personal adjustment to hearing loss (MPAS
Acceptance of Loss, Stress, and Denial subscales), attitudes to hearing aids (HARQ), and
expectations of hearing aids . Only subjects with
complete information were included in each
regression analysis .
The regression analysis of the hours of use
data was based on 113 subjects . Prefitting expectations (X2 = 12 .36, df = 1, p = .0004) and Acceptance of Loss (X2 = 3 .9, df = 1, p = .048) were the
two factors that significantly affected hours of
hearing aid use. Subjects with higher prefitting
expectations (i .e ., lower scores) and better acceptance of loss (i.e ., higher scores) wore their hearing aids more (Fig . 4) .
One hundred and fourteen subjects had complete information and were included in the regression analysis of the satisfaction data . Only the
use of multiple-memory hearing aids had an effect
on overall hearing aid satisfaction (F[1,89] =
5.57, p = .02) . Users of multiple-memory hearing
aids had higher satisfaction scores than those
without. Table 3 shows that satisfaction ratings
were highest for users of multiple microphones,
but only a small group of subjects was fit with
this technology.
Prefitting expectations (F[1,88] = 8.28,
p = .005), employment status (F[2,88] = 5 .28,
p = .007), and the use of multiple-memory
(F[1,88] = 7 .01, p = .01) or multiple-channel
(F[1,881 = 5.18, p = .03) hearing aids all had an
effect on MAPHAB factor 1 easy listening scores
(n = 113) . Factor 1 hearing aid benefit was better for subjects with higher prefitting expectations and for subjects using multiple-memory
or multiple-frequency channel hearing aids .
Part-time workers had higher easy listening
scores than full-time workers, but there was no
difference between those in paid work and
those not working outside the home . The effect
of hearing aid technology on hearing aid outcome is illustrated in Table 3 .
The relationship between employment status and age and between age and hearing loss
was investigated to explore why employment
status affected MAPHAB factor 1 benefit. There
was a difference in the average age of the three
employment groups (F[2,155] = 45 .1, p < .0001) .
Part-time workers were older on average than
full-time workers (66 .7 vs 56 .4 years on average),
but subjects not employed outside the home
were the oldest (mean = 73 .7 years) . As expected,
hearing loss increased with age (F[2,145] = 3 .87,
p = .02) . Thus, part-time workers (n = 13) were
older and had greater hearing loss than full-time
workers (n = 25), who were younger and less
hearing impaired on average than the largest
group of subjects who were not employed
(n = 120) .
Prefitting expectations (F[1,801= 4 .33, p = .04)
and use of WDRC hearing aids (F[1,80] = 5 .18,
p = .03) affected MAPHAB factor 2 difficult listening scores (n = 105) . Greater hearing aid benefit for difficult listening situations was associated
with better expectations and with use of WDRC .
There was also a trend toward greater benefit in
difficult listening situations with use of multiplememory hearing aids (F[1,801 = 3 .48, p = .07) .
No factors were found to significantly influence MAPHAB factor 3 benefit, listening to
aversive sounds (n = 109) . There was, however, a trend of better factor 3 benefit (i .e .,
aided sounds less aversive relative to unaided)
associated with use of multiple-memory aids
(F[1,84] = 3 .77, p = .06) .
DISCUSSION
" Accept
O Expect
<4 hours
4+ hours
Figure 4 Mean expectation (excluding item 9) and
Acceptance of Loss scores for subjects wearing their hearing aids <4 hours and 4+ hours. Results are shown for
subjects completing at least seven of the Expectations
items (n = 154) and all Acceptance of Loss items (n = 158) .
Error bars show standard errors .
Hearing Aid Use Time
The majority of subjects reported using their
hearing aids for over 4 hours per day. This is consistent with the findings of previous studies in
New Zealand (Jerram and Purdy, 1997 ; Purdy
and Jerram,1998) and North America (Cox and
Gilmore, 1990 ; Cox and Rivera, 1992 ; Cox and
Alexander, 1995 ; Humes et al, 1996). Based on
his extensive MarkeTrak IV survey of hearing
aid users, Kochkin (1995) concluded that daily
hearing aid use of 4 hours or more is an indicator of hearing aid success. Some hearing aid
71
Journal of the American Academy of Audiology/Volume 12, Number 2, February 2001
Table 3 Means and SDs for Satisfaction and MAPHAB Factors 1, 2, and 3 Benefit
for the Different Hearing Aid Technologies Used by Subjects in the Study
Technology
WDRC
Other C
PC
Multiband
Multiple memory
Multiple microphone
n
88
53
6
68
35
15
Satisfaction
Factor 1
Factor 2
Mean (SD)
Factor 3
Mean (SD)
Mean (SD)
Mean (SD)
15 .2
15 .1
15 .1
14 .8
15 .9
16 .3
24 .4
23 .6
16 .8
27 .6
19 .7
28 .1
26 .3
25 .3
18 .6
25 .5
24 .5
20 .1
(3 .6)
(3 .2)
(2 .8)
(3 .5)
(2 .9)
(3 .7)
(21 .4)
(24 .3)
(34 .8)
(20 .5)
(25 .5)
(20 .6)
(18 .4)
(18 .5)
(33 .4)
(17 .3)
(17 .2)
(12 .3)
-5 .8
-5 .1
2 .78
-3 .6
-2 .7
-12 .3
To enable comparison with Table 2, data presented are for subjects who completed at least 80% of the MAPHAB (n = 146) .
Other C = other compression circuits (input or output).
users with very specific and limited hearing aid
listening needs may be successful users, however, despite using their aids very little . Selfreporting of hearing aid use can be misleading
(Humes et al, 1996 ; Taubman et al, 1999), since
subjects tend to exaggerate actual hearing aid use
time . Despite this limitation, self-report of hearing aid use appears to be a valuable and widely
recognized dimension of hearing aid outcome
(Humes, 1999).
Hearing Aid Benefit
Hearing aid benefit was measured using
the MAPHAB (Purdy and Jerram, 1998). As
seen previously, benefit was slightly greater for
difficult than for easy listening situations (e .g .,
Cox and Alexander, 1995 ; Valente et al, 1995,
1998) . Studies investigating older versus newer
hearing aid technologies typically report mean
APHAB benefit values in the range of 20 to 35
percent for the three APHAB listening subscales
(e.g., Valente et al, 1995, 1998 ; Preves et al,
1999), although, occasionally, benefit over 40
percent is obtained . Mean benefit scores for the
easy and difficult listening factors in the present
study fall within the range of values previously
reported, despite the use of a different scale.
Many subjects were unable to complete the
MAPHAB . We have noted previously that older
clients in particular may have difficulty with
some of the APHAB questions (Purdy and Jerram,
1998) . The reversal of a number of the items to
prevent bias is one source of confusion (Noble,
1998), and our use of a more detailed 100-point
scale also may have made the questionnaire too
complex for some clients. A recent study showed
that, based on respondent preference and
test--retest reliability, a 10-point scale is optimal
(Preston and Colman, 2000).
72
(25 .2)
(24 .5)
(18 .8)
(26 .0)
(23 .5)
(17 .9)
As seen in other studies (Cox and Alexander, 1995 ; Valente et al, 1995, 1998 ; Preves et al,
1999), hearing aids were not beneficial for listening to aversive environmental sounds . The
amount of "negative benefit" was considerably
less, however, than values reported previously,
presumably reflecting the greater loudness comfort provided by the WDRC technology that the
majority of subjects were using. WDRC has
gained popularity because it provides better
speech intelligibility in quiet compared with
linear amplification (Humes et al, 1999 ; Walden
et al, 1999) and greater listening comfort across
a wide range of situations (Jenstad et al, 1999).
Superior performance has not been found consistently in noisy environments, however (Kam
and Wong, 1999 ; Souza and Turner, 1999).
Previous studies have shown that the
APHAB can distinguish between different types
of high-performance hearing aids (Valente et
al, 1995, 1998 ; Arlinger et al, 1998 ; Berninger
and Karlsson, 1999 ; Preves et al, 1999). Consistent with Kochkin's (1996, 2000) reports of the
listening advantages provided by higherperformance hearing aids, benefit was significantly greater in easy listening situations for
multiple-memory and multiple-channel hearing aids . This is not surprising, since these technologies allow greater fitting and user flexibility.
Benefit in difficult listening situations was
greater for WDRC hearing aids . Although some
studies have failed to find speech reception benefits of WDRC in noise (Kam and Wong, 1999 ;
Souza and Turner, 1999), other studies have
seen WDRC advantages in noise compared with
linear technology (e .g., Humes et al, 1999). In the
present study, it is possible that clients using
WDRC hearing aids experienced greater hearing aid benefit in difficult listening situations
because of the way their audiologists selected the
Predictors of Hearing Aid Outcome/Jerram and Purdy
technology. Clients using WDRC had milder
hearing losses (by 5 dB on average) than clients
fitted with non-WDRC aids ; thus, they may
have experienced greater benefit in noise due to
having less cochlear pathology. The advantages
of multiple-microphone hearing aids in noise
are well documented and have been demonstrated using the APHAB (e .g ., Valente et al,
1995 ; Preves et al, 1999) . Therefore, it was surprising that multiple-microphone technology
was not a predictor of MAPHAB factor 2 benefit . This could be due to the small number of subjects fitted with multiple-microphone hearing
aids . It is also possible that audiologists only prescribed this technology for clients with more
severe speech in noise problems .
Satisfaction
In general, the subjects were very satisfied
with their hearing aids . The mean rating of
76 percent was slightly higher than the value of
71 percent found by Purdy and Jerram (1998)
using the same scale. Subjects in the present
study had new hearing aids, and there was a relatively high proportion of high-performance
hearing aids fitted . Kochkin (1995, 1996) found
that satisfaction is greater for newer hearing aids
and newer technologies . Mean scores reported
by Cox and Alexander (1999) for the Satisfaction
with Amplification in Daily Living (SADL)
ranged from 43 to 91 percent for the individual
items in their satisfaction profile. Although
derived in quite different ways, the 70 percent
global satisfaction value obtained by Cox and
Alexander for the SADL questionnaire and
Kochkin's (1996) reported satisfaction values of
71 to 75 percent for new and high-performance
hearing aids are consistent with the satisfaction
results obtained in the present study.
There were statistically significant positive
correlations between satisfaction and the two
MAPHAB listening factors. Similar to Purdy
and Jerram (1998), the strongest correlation
between hearing aid benefit and satisfaction
was for difficult listening situations, and satisfaction was higher in subjects who wore their
aids more often . This is consistent with Kochkin's
(1993, 1996) finding that satisfaction is highly
related to the number of listening situations in
which the wearer's needs are met. Kochkin
(1999, 2000) has used the term "multiple environmental listening utility" (MELD) to refer to
the ability of hearing aids to provide good listening satisfaction in a range of environments,
including noise. Consistent with Kochkin's
MELU concept, users of multiple-memory hearing aids were significantly more satisfied with
their hearing aids .
Hyde and Riko (1994) criticized global measures of overall satisfaction on the basis that they
confound features of hearing aid performance,
convenience, aid physical characteristics, and
stigma . This could explain why only one of the
factors investigated (multiple memories) was
predictive of satisfaction . Future research in
this area may be more successful if a more specific, differentiated satisfaction scale such as
the SADL (Cox and Alexander, 1999) is used .
Demographic Factors
Part-time workers had higher easy listening
hearing aid benefit scores than full-time workers .
This is probably explained by the greater degree
of hearing loss seen in older subjects, who made
up the majority of part-time workers . Previous
hearing aid experience (Pawing and Philip, 1991),
age (Mulrow et al, 1992 ; Crowley and Nabelek,
1996 ; Jerram and Purdy, 1997), and degree of
hearing loss (Brooks, 1985 ; Kochkin, 1995) have
been found previously to affect hearing aid outcome but were not significant factors in the present study. Differences in subject groups across
studies could account for these differences .
Attitudes
With the exception of one item, internal
reliability of the HARQ hearing aid stigma factor was very good, as was found by Hallam and
Brooks (1996) . Hallam and Brooks (1996) also
obtained a relatively low item loading for item
9, which was excluded from the present analysis . In contrast to previous studies (Hickson et
al, 1986, 1999 ; Brooks, 1989 ; Brooks and Hallam, 1998), attitudes toward hearing aids were
not predictive of hearing aid outcome . Brooks
(1989) investigated attitude with a single question that was similar in content to item 9 of the
HARQ, and found that subjects with a more
positive attitude wore their hearing aids more
when they were evaluated 4 months after the
fitting .
Brooks and Hallam (1998) assessed attitudes to hearing loss and hearing aids using
the 40-item HARQ, which has seven subscales,
including the Hearing Aid Stigma subscale used
in the present study. In agreement with the present study, an attitude that wearing a hearing
aid is stigmatizing was not predictive of hearing aid outcome. Attitudes to hearing loss and
73
Journal of the American Academy of Audiology/Volume 12, Number 2, February 2001
hearing aids measured by other subscales (feelings of personal distress/inadequacy due to hearing loss, minimization of hearing impairment,
and not wanting/needing hearing aids) were
predictive of outcome. Two of these factors (distress/inadequacy and minimization) are similar
in content to the CPHI personal adjustment
subscales. Stigma associated with hearing loss
and hearing aids is a barrier to hearing aid use
(Kochkin, 1993 ; Hetu, 1996 ; Arnold and MacKenzie, 1998). Hetu (1996) has shown that adults
who develop a hearing loss are reluctant to
acknowledge hearing difficulties because of fear
of stigmatization and embarrassment . The finding of no relationship between the perception of
hearing aids as stigmatizing and hearing aid outcome suggests that, in general, individuals who
accept hearing aids have generally overcome
this fear. The range of responses to the HARQ
(see Table 1) indicates that some individual subjects did have very poor attitudes toward hearing aids ; thus, for some subjects, concerns about
stigma may have still been a problem .
Expectations
The poor internal reliability of the 12 items
of Seyfried's (1990) expectations questionnaire
also was seen by Bentler et al (1993) . We were
not able to replicate the good reliability reported
by Bentler et al for a subset of five expectations
items and instead obtained moderately good
reliability for a different subset of nine items.
Higher prefitting expectations were associated with higher daily hearing aid use time .
Expectations also influenced hearing aid benefit in easy and difficult listening situations . On
average, subjects had positive expectations
(mean = 2.3 ± 0.6). The mean expectations score
plus 1 SD falls in the middle of the 6-point scale.
An expectations score greater than 3, indicating
low expectations, could be used as an indicator
for a potentially poorer outcome . Further
research is needed to determine whether additional prefitting counselling (e .g., Brooks, 1979,
1985 ; Brooks and Johnson, 1981) would improve
hearing aid outcomes for these individuals with
low expectations .
Higher expectations scores predicted greater
hearing aid benefit in noisy and in quiet listening situations . In contrast, Schum (1999) found
a modest negative correlation between prefitting
expectations measured using the Hearing Aid
Needs Assessment questionnaire and speech in
noise scores on the Hearing Aid Performance
Inventory (HAPI, Walden et al, 1984). Thus, in
74
contrast to the present study, higher expectations
of listening performance were associated with
poorer listening outcome . Seyfried (1990) found
no relationship between expectations (measured
using Bentler et al's [ 1993] subset of items) and
hearing aid benefit measured using the Understanding Speech subsection of the Hearing Performance Inventory (HPI, Giolas et al, 1979). The
HAPI and HPI directly assess aided performance and thus differ from the subtractive benefit measure obtained using the MAPHAB in the
present study. Another difference between studies is that Schum only examined expectations of
aided listening ability, whereas Seyfried's expectations questionnaire assesses a range of expectations including the ability to handle hearing
aids and physical comfort.
Personal Adjustment
As has been found previously (Demorest
and Erdman, 1987, 1989 ; Jerram and Purdy,
1999), the CPHI Acceptance of Loss, Stress, and
Denial subscales had excellent internal reliability. Acceptance of Loss subscale scores were
related to hours of use. Crowley and Nabelek
(1996) also found a predictive relationship
between CPHI Personal Adjustment scores
(13 subscales including Acceptance of Loss) and
hearing aid performance. Although hearing aid
performance and hours of use are not the same,
they are related (Purdy and Jerram, 1998). The
original CPHI is a very long questionnaire that
examines many aspects of hearing loss (Demorest and Erdman, 1986). Using the whole scale,
Cox and Rivera (1992) found no relationship
between CPHI and PHAB results. This is consistent with our findings of no relationship
between MAPHAB benefit and CPHI Acceptance of Loss, Stress, or Denial scores .
A high CPHI score indicates good personal
adjustment to hearing loss . Thus, the mean
score of 3.7 - 1.3 for the Acceptance of Loss
scale indicates that the subjects in this study
were generally "well adjusted" to their hearing
loss. This is probably not surprising for subjects
who were willing to participate in hearing aid
research requiring a reasonable time commitment, some of whom had worn hearing aids previously. Similar Acceptance of Loss scores have
been reported in other studies (Demorest and
Erdman, 1989 ; Cox and Rivera, 1992 ; Garsteki
and Erler, 1998 ; Erdman and Demorest, 1998 ;
Jerram and Purdy, 1999). Forty-four percent of
subjects had low Acceptance of Loss scores of
2 or less . Pre- and/or postfitting counselling
Predictors of Hearing Aid Outcome/Jerram and Purdy
might improve hearing aid outcomes for these
individuals (Brooks, 1989) .
SUMMARY AND CONCLUSIONS
T
his study evaluated the effects of a number of predictor variables on three mea-
sures of hearing aid outcome, hours of use,
subjective benefit, and overall satisfaction .
Subjects completed three questionnaires prior
to hearing aid fitting that examined personal
adjustment to hearing loss, attitudes to hearing aids, and expectations of hearing aids .
These questionnaires had good internal reliability after exclusion of some items from the
attitudes and expectation scales . On average,
subjects had a moderate level of personal
adjustment and positive attitudes and expectations, but there was considerable variability
across individuals . Subjects were generally
satisfied with their hearing aids and had good
subjective benefit . The majority of subjects
reported using their aids more than 4 hours per
day. Subjects who used their aids more had
higher benefit and satisfaction ratings . Satisfaction was related to benefit, particularly for
difficult listening situations .
Demographic factors did not affect hearing
aid outcome. Multiple-memory hearing aids
increased satisfaction and benefit. Multiplechannel and WDRC instruments were associated
with greater hearing aid benefit, but the WDRC
effect may have resulted from audiologists using
WDRC in subjects with lesser degrees of hearing loss . On average, satisfaction was highest for
multiple-microphone aids, but this effect was not
significant, presumably due to the small number of subjects fitted with this technology. The
results support the use of newer hearing aid
technologies in order to maximize hearing aid
outcomes .
Subjects with better prefitting expectations
of hearing aids and better personal adjustment
to hearing loss measured using the CPHI Acceptance of Loss subscale used their hearing aids
more . Expectations also positively influenced
benefit in easy and difficult listening situations .
The predictive influence of prefitting expecta-
tions and acceptance of hearing loss on hearing
aid use and benefit suggests that these factors
should be regularly assessed prior to hearing aid
fitting. Prefitting and follow-up counselling may
be beneficial in cases where expectations of
hearing aids and acceptance of hearing loss are
poor.
Acknowledgments. The authors would like to acknowledge the support for this study provided by New Zealand
public hospital and private audiology clinic staff and
clients. Funding for this research was provided by the
Deafness Research Foundation of New Zealand . We also
thank Elizabeth Robinson from the University of
Auckland's Biostatistical Unit for her support and statistical analysis of the data .
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APPENDIX
Seyfried (1990) Expectations Checklist
I will have difficulty operating the controls on my hearing aid(s) .
My hearing aids will fit comfortably.
My hearing aids will make speech more distinct .
My family believes my hearing aids will help me communicate better.
I will have difficulty inserting and removing my hearing aid(s) .
I will adjust slowly to my hearing aids .
In some noisy situations, my hearing aids will be helpful.
I will need my hearing aids in most listening situations in which I find myself.
When I am using my hearing aid(s), I will need to watch speakers' faces and ask them for repetitions occasionally.
10 . When I am speaking to others in a quiet room, my hearing aid(s) will be helpful.
11 . When I am using my hearing aid(s), some sounds will be uncomfortably loud .
12 . I will feel self-conscious when I am wearing my hearing aids .
Hearing Attitudes in Rehabilitation Questionnaire (HARQ)
1.
2.
3.
4.
5.
6.
7.
78
1 think that if you wear a hearing aid people tend to ignore you.
I would stand out in a crowd wearing a hearing aid.
Many people don't know how to react to you when you have a hearing aid.
It would make me feel old to wear a hearing aid.
If I wear a hearing aid, people will probably think I'm a bit stupid .
It would embarrass me to have to wear a hearing aid.
I think people react differently to you when you are wearing a hearing aid .
Predictors of Hearing Aid Outcome/Jerram and Purdy
8 . From what I know, hearing aids don't help a great deal .
9. I think the behind-the-ear aids are really quite small and inconspicuous .
Communication Profile for the Hearing Impaired (CPHI) Subscales
(Items 1-9 = Acceptance of Loss, 10-17 = Stress, 18-25 = Denial)
1 . 1 try to give the impression of normal hearing.
2. I try to hide my hearing problem.
3. Sometimes I'm ashamed of my hearing problems .
4. I'm sensitive about my hearing loss .
5. I find it difficult to admit to others that I have a hearing problem .
6. It bothers me to admit that I have a hearing loss .
7. I can't talk to people about my hearing loss .
8. I have a hard time accepting the fact that I have a hearing loss .
9 . I'd rather miss part of a conversation than admit that I have a hearing loss .
10 . I feel threatened by many communication situations due to difficulty hearing .
11 . I'm not very relaxed when conversing with others .
12 . I'm not very comfortable in most communication situations .
13 . I get very tense because of my hearing loss .
14 . When I have trouble hearing, I become nervous.
15 . I worry about looking stupid when I can't understand what someone has said .
16 . Straining to hear upsets me .
17 .
18 .
19 .
20 .
21 .
22 .
23 .
24 .
25 .
When I can't understand what's being said, I feel tense and anxious.
Sometimes I feel left out when I can't follow the conversation of those I'm with .
I sometimes get annoyed when I have trouble hearing.
When I have trouble hearing, I feel frustrated .
It's frustrating when people refuse to repeat what they've said .
Sometimes when I misunderstand what someone has said, I feel foolish.
I sometimes get angry with myself when I can't hear what people are saying.
Sometimes I feel tense when I can't understand what someone is saying.
1 sometimes feel embarrassed when I misunderstand what someone has said .