Science Assignment due

Do Experienced Hearing Aid Users Know How to Use Their Hearing Aids Correctly?

Jamie L. Desjardins Karen A. Doherty Syracuse University, Syracuse, NY

Purpose: To assess experienced hearing aid users’ ability to use their hearing aids correctly. Method: In this study, we developed the Practi- cal Hearing Aid Skills Test (PHAST) to objectively test a hearing aid user ’s ability to manipulate his or her hearing aids. The PHAST requires hearing aid users to perform 8 hearing aid care and use tasks that are basic skills typically taught to new hearing aid users at the time of their hearing aid fitting. The PHAST was administered to a group of 50 experienced hearing aid users. In addition, participants were administered ques- tionnaires about hearing aid satisfaction (i.e., Satisfaction With Amplification in Daily Life; R. M. Cox & G. C. Alexander, 1999), benefit (i.e., Ab- breviated Profile of Hearing Aid Benefit; R. M. Cox & G. C. Alexander, 1995), and use. Results: Participants’ performance on the PHAST ranged from 48% to 100%, and the scores were

normally distributed around the mean (78.56%). No significant relationship was observed between the PHAST and any of the other tests adminis- tered in this study. The only variable significantly associated with participants’ performance on the PHAST was age. Conclusions: Results from this study suggest that experienced hearing aid users range from having an excellent understanding of how to use their hearing aids to a poor understanding. The variability in performance among experienced hearing aid users highlights the importance of directly assessing a client’s ability to use his or her hearing aids.

Key Words: hearing aids, aging, hearing loss, hearing aid use

Hearing aids are the most common intervention for people diagnosed with sensorineural hearing loss, which is the most prevalent type of hearing loss in

adults (Gatehouse, 2002). Many individuals with hearing loss become frustrated because of missed communication and as a result avoid social activities, spend less time with friends, have family problems, and feel isolated and depressed (National Council on Aging, 1999). Thus, it is critical for individuals with hearing loss to maximize the use of their hearing aids. Unfortunately, a significant proportion of hearing aid users report being dissatisfied with their hearing aids (Kochkin, 2000, 2005), and as a result, many of these individuals do not use their hearing aids.

Several studies have examined factors that contribute to why some individuals do not use their hearing aids (e.g., Baumfield & Dillon, 2001; Brooks, 1994; Garstecki & Erler, 1998; Hickson, Hamilton, & Orange, 1986; Humes, 2006; Kochkin, 1996; Sorri, Luotonen, & Laitakari, 1984). These include degree of hearing loss (Kochkin, 1996), gender (Garstecki & Erler, 1998), cosmetic appeal, comfort, sound quality (Brooks, 1994), and the hearing aid user’s ability to manage his or her hearing aids (Baumfield & Dillon, 2001; Hickson et al., 1986; Humes, 2006; Sorri et al., 1984). In the

present study we focus on answering a question related to the last of these factors: How well can hearing aid users manip- ulate their hearing aids?

During their 30- to 45-day hearing aid trial period, new hearing aid users are typically counseled over several ses- sions on hearing aid use, maintenance, warranty information, and methods of how to communicate effectively while using hearing aids. According to data from the MarkeTrak VII survey, dispensers spent on average a total of 45 min during the hearing aid trial period instructing individuals on how to use and care for their hearing aids (Kochkin, 2005). Thus, a new hearing aid user is expected to com- prehend a fair amount of new information in a relatively short period of time. While this may be a difficult task for a new hearing aid user, it could be especially problematic for older hearing aid users who may have age-related deficien- cies in working memory. Older hearing aid users may be unable to process and store all of the new hearing aid infor- mation, or they may forget critical hearing aid information (Salthouse, 1990). In either case, these individuals could become dissatisfied with their hearing aids.

It is typical for clinicians to simply ask their new hearing aid clients at the end of their trial period if they are comfortable

Research and Technology Article

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with how to use their hearing aids. If the answer is “yes,” the clinician generally feels confident that the information he or she explained about the hearing aids has been fully com- prehended by the hearing aid user, and they provide no further counseling on these topics. Also, some clinicians will use self-report hearing aid questionnaires to determine hearing aid benefit and satisfaction. However, these types of self- assessments often have little correlation with objective mea- sures of hearing aid performance or benefit. For example, the correlation between subjective and objective measures of hearing aid benefit has been shown to be low (e.g., Cox & Alexander, 1992; Valente, Fabry, Potts, & Sandlin, 1998). In addition, it has been shown that hearing aid users’ responses on some hearing aid outcome questionnaires are related to their individual personality attributes (Cox, Alexander, & Gray, 1999; Gatehouse, 1994; Hutchinson, Duffy, & Kelly, 2005). Thus, when based on self-report measures, it may appear to both the clinician and the new hearing aid user that all aspects of the new aids are understood and the user is satisfied, when in fact this is not completely true.

Consequently, current practice leaves clinicians unable to objectively identify how well hearing aid users are able to use and care for their hearing aids. This could be problematic because we know hearing aid users’ ability to manipulate their hearing aid is significantly related to hearing aid use. For example, Humes (2006) reported that individuals who had greater difficulty managing and manipulating their hear- ing aids 2 weeks after their initial hearing aid fitting were not as satisfied, perceived less benefit, and reported lower use of their hearing aids compared with individuals with fewer problems at 2 weeks postfit. Thus, individuals who are wearing hearing aids without fully understanding how to use them correctly may not be receiving maximum ben- efit from their hearing aids. In the worst case scenario, this could result in the hearing aid user rejecting amplification altogether.

The purpose of the present study was to determine whether experienced hearing aid users know how to correctly use their hearing aids. In this study, we developed the Practical Hearing Aid Skills Test (PHAST), an objective test of a hearing aid user’s ability to manipulate his or her hearing aids. The PHAST was evaluated on a group of experienced hearing aid users who wore various types and models of hearing aids. Performance on the PHASTwas compared with performance on subjective measures of hearing aid benefit and satisfaction to determine whether PHAST performance could be predicted from tests that are currently available in the clinic.

Method Participants

Fifty experienced hearing aid users (27men and 23women) between 46 and 89 years of age (M = 75.36, SD = 9.33) were recruited to participate in this study based on an a priori power analysis of a Pearson correlation (r = .4) using p = .05 and power = .8 (Cohen, 1988). All participants wore a hearing aid for at least 1 year (M = 8.68, SD = 5.31) and passed the Short Portable Mental Health Status Questionnaire (Pfeiffer, 1975).

In addition, all participants reported that they were personally responsible for the use and care of their hearing aid(s). Par- ticipants were recruited via newspaper and radio advertise- ments and were paid an hourly wage for their participation in the study. We recruited participants who were fit with hear- ing aids by a wide range of audiologists and hearing aid dis- pensers, and who wore many different models and styles of hearing aids, in an effort to study the PHAST on a wide range of experienced hearing aid users. Specifically, a total of 11 hear- ing aid clinics (spanning a distance of approximately 110miles in the Central New York area), 5 hearing aid dealers, and 10 dispensing audiologists were represented in the study sample.

For each participant, air-conduction thresholds were mea- sured in a double-walled, sound-proof booth at octave fre- quencies between 0.25 kHz and 8 kHz, and at 6 kHz, using a GSI-16 audiometer with TDH-50 supra-aural earphones (American National Standards Institute, 2004). Figure 1 shows the mean pure-tone thresholds for the left and right ears of the 50 participants.

Test Measures TheAbbreviated Profile of HearingAid Benefit (APHAB;

Cox&Alexander, 1995) was used to assess benefit based on a 24-item self-assessment inventory. Benefit was determined by comparing the participants’ reported listening difficulties with and without the use of their hearing aids in different listening situations. The Satisfaction With Amplification in Daily Life (SADL; Cox & Alexander, 1999) was used to measure hearing aid satisfaction across four subscales: Posi- tive Effect, Service and Cost, Negative Features, and Personal Image. Last, we asked participants to answer 22 questions about their hearing aid use, hearing aid knowledge, and de- mographic hearing aid information. We refer to this measure throughout the study as the hearing aid lab questionnaire. This was a questionnaire that we developed in our lab for this study.

Figure 1. Mean pure-tone thresholds (in dBHL) for 50 participants’ right and left ears. Error bars represent ±1 SD.

70 American Journal of Audiology • Vol. 18 • 69–76 • June 2009

The PHAST was used to objectively measure hearing aid users’ ability to manipulate their hearing aids. The PHAST requires hearing aid users to perform 8 hearing aid skills. These 8 skills are listed in the hearing aid instruction manuals of severalmajor hearing aidmanufacturers (e.g., GNReSound, 2005; Oticon, 2003; Siemens, 2005), and are typically taught to new hearing aid users during their initial hearing aid fitting appointment. In developing the PHAST, two independent, licensed audiologists with more than 10 years of hearing aid experience provided feedback on the appropriateness of the skills selected for the PHAST. Based on their feedback, 2 of the 10 original PHAST tasks were deleted from the test and no new test items were added. The 8 tasks on the PHAST cover the following skills: (a) hearing aid insertion, (b) hear- ing aid removal, (c) opening the battery door, (d) changing the hearing aid battery, (e) cleaning the aid, (f ) manipulating the volume control, (g) telephone use, and (h) use of the directional microphone or noise program. See the Appendix for a description of the PHAST.

During administration of the PHAST, participants were verbally instructed and also given a handout with instruc- tions that included a list of the PHAST tasks they were asked to perform. The examiner judged each participant’s perfor- mance on the PHAST using a 5-point Likert scale with val- ues of excellent (4), better than satisfactory (3), satisfactory (2), less than satisfactory (1), and cannot perform (0). Spe- cifically, a given PHAST task was judged by the examiner as excellent when the participant completed the task with no mistakes, better than satisfactory when the participant made one mistake but still successfully completed the task, satis- factory when the participant made more than one mistake but successfully completed the task, and less than satisfactory when the participant attempted the task but could not com- plete it successfully or used deviant means to complete the task (e.g., removed hearing aid to adjust the volume control). When a participant could not perform the task at all, they were given a score of 0.

To facilitate consistent scoring of the eight PHAST tasks across all 50 participants, each PHAST task was broken down into the necessary actions a hearing aid user would need to perform to successfully complete the task. On the examiner’s score sheet, there were specific actions listed under each of the eight PHAST tasks, which the examiner individually assessed and scored for each participant. For example, to successfully perform the PHAST task “use the telephone with your hearing aid(s),” the hearing aid user would need to per- form the following two actions: use the correct program/t-coil switch (if applicable) and correctly place the phone in rela- tion to the hearing aid. The examiner used the 5-point Likert scale described above to score the participant’s performance on each of these two actions. Each action was weighted equally to compute the participant’s skill score for the “use the telephone with your hearing aid(s)” task.

Participants’ performance on each of the eight PHAST tasks contributed equally to their final PHAST score. Thus, the total points obtained from each of the eight tasks were summed to compute an individual’s total raw PHAST score. Maximum performance on the PHAST is 32 points (8 skills × 4 points [excellent]). For example, if an individ- ual had excellent (4) performance on seven skills and poor

(1) performance on one skill, his or her raw PHAST score would be 29 [(7 × 4 = 28) + (1 × 1 = 1)]. The raw PHAST score was divided by the maximum possible points on the exam and then multiplied by 100 to obtain a percentage correct score. Note that the maximum possible points on the PHAST were adjusted if a question was not applicable (e.g., no manual noise program on the hearing aid).

The percentage correct scores were defined as excellent (90%–100%), good (80%–89%), fair (65%–79%), and poor (below 65%) performance. These categories were estab- lished based on the fact that the skills included in the PHAST are very “basic” and essential for proper functioning of the hearing aid (e.g., GNReSound, 2005; Oticon, 2003; Siemens, 2005). Thus, if an individual obtained less than 100% and at least 90% on the PHAST, they were unable to perform one task completely or performed several tasks less than excel- lent. Less than 90% but at least 80% on the PHAST indicated an individual could not perform two tasks completely or performed less than excellent on several tasks. Less than 80% and at least 65% indicated an individual could not per- form three tasks completely or performed less than excellent on several tasks. If an individual could not perform three or more of these basic hearing aid skill tasks, they were de- fined as poor performers.

Procedure Data were collected over one 2-hr test session by a single

examiner who was a licensed audiologist with more than 5 years of hearing aid dispensing experience. First, the ex- aminer obtained information about the participants’ hearing aid history. Participants were then asked to complete three questionnaires—the SADL (Cox & Alexander, 1999), the APHAB (Cox & Alexander, 1995), and the hearing aid lab questionnaire, which were presented in random order. It took participants approximately 30 to 45 min to complete all three questionnaires. Upon completion of the question- naires, participants’ hearing thresholds were obtained.

The PHAST was always the last test administered, and it was always administered at least 1.5 hr after the hearing aid lab questionnaire was administered. This was done to prevent participants from feeling like they were being tested on skills for which they had just been asked to judge their own performance. For example, 3 of the 22 questions on the hearing aid lab questionnaire are directly related to three skills on the PHAST. The examiner read the participants’ responses on the questionnaires after the study was completed.

Results To assess interrater reliability, the examiner and one other

certified audiologist independently scored the PHAST for 3 participants selected at random. No significant differences in PHAST scores were reported between these two examiners on any of the eight tasks. Thus, interrater reliability was excellent (intraclass correlation coefficient = 1.0; Shrout & Fleiss, 1979).

Participants’ scores on the PHAST ranged from 48% to 100% (M = 78.56%, SD = 12.27%) and were normally distrib- uted (skewness = –0.319, standard error of skewness = 0.337)

Desjardins & Doherty: Correct Use of Hearing Aids 71

around the mean, as shown in Figure 2. This suggests experi- enced hearing aid users range from having an excellent understanding of how to use their hearing aids to a poor understanding. The percentage of participants who scored below satisfactory on one or more of the eight PHAST skill tasks is shown in Figure 3. None of the 50 participants per- formed below satisfactory on the hearing aid removal and opening the battery door tasks. Poorest performance was observed on use of the telephone, how to clean the aid, and use of the noise program. See Table 1 for the means and standard errors of the mean for each PHAST task.

Univariate analysis was used to examine the association between PHAST scores and participant demographics (age, gender, and pure-tone thresholds at 500 Hz, 1000 Hz, and 2000 Hz averaged across ears [mean pure-tone average]), hearing aid characteristics (style of hearing aid and type of hearing aid circuit), and hearing aid use (the number of years the hearing aid was worn and the number of hours the hear- ing aid was used per day). An analysis of variance (ANOVA) was employed to test the categorical variables, and a Pearson correlation was used to evaluate the continuous variables with participants’ PHAST scores. All nonnumeric variables were coded into numeric values such that gender was assigned a 0 for male and 1 for female, style of hearing aid was coded with a 1 for in-the-canal, 2 for in-the-ear, and 3 for behind-the- ear aids. Type of hearing aid was coded using ordered cate- gories based on the level of technological sophistication of the hearing aid circuit. Analog hearing aids were coded 1, digital hearing aids with one program were coded 2, and digital hearing aids with more than one program were coded 3.

A summary of the independent variables included in the univariate analysis is provided in Table 2. Given the use of seven separate ANOVA and Pearson correlation analyses, the criterion significance level was adjusted for multiple comparisons by dividing the criterion significance level by the number of separate analyses (i.e., 0.10/7), which resulted in an overall significance level of p ≤ .014. Using this significance criteria, age was the only variable significantly

associated with participants’ PHAST scores (see Figure 4). See Table 3 for the F values, Pearson correlations, and significance levels of all the independent variables in the univariate analysis.

The relationship between participants’ level of satisfac- tion with the hearing aid information they were provided at the time they were fit with the device was determined based on participants’ responses to two items on the hearing aid lab questionnaire: (a) “I was satisfied with the information provided to me about how to use my current hearing aid(s) during my hearing aid trial period” and (b) “I was satisfied with the information provided to me about caring for my current hearing aid(s) during my hearing aid trial period.” A summated rating scale was used to quantify the construct satisfaction with hearing aid information because measure- ment error averages out when individual scores on multiple items of a questionnaire are summed to obtain a total score (Spector, 1992). Internal consistency reliability analysis of the computed measure satisfaction with hearing aid infor- mationwas performed and found to be excellent (Cronbach’s

Table 1. Mean Practical Hearing Aid Skills Test (PHAST) scores and the standard errors of the mean for each of the eight PHAST skill tasks.

PHAST task Mean score (%) SEM

Battery door 97.25 0.895 Insertion 95.50 1.81 Removal 94.75 1.71 Volume control (n = 23) 90.74 5.36 Change battery 88.25 2.45 Noise (n = 18) 48.61 11.86 Telephone 46.50 6.04 Cleaning 42.66 3.73

Note. n = 50.

Figure 3. The percentage of participants scoring below satisfactory for each PHAST skill task. VC = volume control.

Figure 2. Frequency histogram showing the distribution of Practical Hearing Aid Skills Test (PHAST) scores for 50 participants, as well as the group mean and standard deviation.

72 American Journal of Audiology • Vol. 18 • 69–76 • June 2009

alpha = .802). A Pearson correlation found no significant ( p = .171) association between PHAST scores and partici- pants’ satisfaction with the hearing aid information they were provided at the time they were fit with their current hearing aids. Thus, participants who performed poorly on the PHAST reported they were satisfied with the information that was provided to them.

Participants’ scores on the global scale of the SADL ranged from 3.3 to 6.2 (M = 4.71, SD = 0.72, 40th percentile).

Overall benefit scores on the APHAB ranged from –1.4 to 57.4 (M = 30.97, SD = 14.53, 35th percentile). Pearson cor- relations were used to determine whether participants’ per- formance on the PHASTwas associated with these subjective measures. Results showed no statistically significant rela- tionship between PHAST scores and the SADL global score ( p = .179) or the APHAB overall benefit score ( p = .817).

Discussion Hearing aid manipulation is an important factor for hear-

ing aid success. There is currently no objective measure available to evaluate a hearing aid user’s ability to manipu- late his or her hearing aids. Typically, this type of information is inferred from informal observation and/or self-report by the hearing aid user. In the present study, the PHAST was developed to measure a hearing aid user’s ability to manip- ulate his or her hearing aids. Participants’ scores on the PHAST were compared to their scores on other subjective (APHAB, SADL, and hearing aid lab questionnaire) hearing aid outcome measures.

The PHAST is easy to administer, taking approximately 10 min to perform and score. In the present study, scores on the PHAST ranged from 48% to 100% and were normally distributed around the mean. Thus, the tasks included in the PHAST are appropriately challenging even for experienced hearing aid users. All of the participants in this study had worn hearing aids for at least 1 year, and 38% of them wore hearing aids for more than 10 years. Therefore, it was not too surprising that none of the participants scored below 48% on the PHAST. Experienced hearing aid users were intention- ally selected for the initial testing and piloting of the PHAST because we were interested to know whether the PHASTwas sensitive enough to measure a range in performance for a group of participants who have experience using a hearing aid. We are preparing to test the PHAST on a group of new hearing aid users during their hearing aid trial period. We would expect to see a larger range in performance on the PHAST from such a group compared to the experienced hearing aid users in the present study.

All of the participants in this study were able to satisfac- torily insert their hearing aid and open the battery door. Sim- ilarly, almost all of the participants were able to satisfactorily remove and replace their hearing aid battery. This would be expected given that all of the participants in this study inde- pendently used and cared for their hearing aid(s) for at least

Figure 4. Mean scores on the PHAST by age (in years) for 50 (46–64, n = 5; 65–75, n = 18; 76–89, n = 27) participants. Error bars represent ±1 SEM.

Table 3. F values, Pearson correlations, and significance levels of all the independent variables in the univariate analysis.

Variable F r p

Gender 0.021 .885 Style of hearing aid 1.72 .190 Type of hearing aid circuit 0.284 .754 Hearing aid use in years 2.18 .103 Hours hearing aid worn per day 5.03 .030 Age –.310 .014* Mean pure-tone-average –.303 .016

Note. n = 50.

Table 2. Summary data of the variables included in the univariate analysis (n = 50).

Variable % participants M SD

Participant demographics Age 75.36 9.328 Pure-tone threshold 48.8 dB HL 12.65 Gender

Male 54 Female 46

Hearing aid characteristics Style

In-the-canal 27 In-the-ear 44 Behind-the-ear 28

Type of circuit Analog 32 Digital 1 program 32 Digital > 1 program 36

Hearing aid use Years

1–2 10 2–5 20 5–10 32 10+ 38

Hours per day <2 6 2–5 18 6–12 38 12+ 38

Desjardins & Doherty: Correct Use of Hearing Aids 73

1 year. However, several tasks on the PHAST proved to be challenging for most participants. For example, more than three quarters of the participants were not able to satisfactorily use the telephone with their hearing aid.

Participants who did not have a t-coil or telephone pro- gram had difficulty correctly positioning the telephone to prevent feedback. In addition, participants who had behind- the-ear hearing aids and a manual t-coil switch had difficulty correctly positioning the telephone to the hearing aid micro- phone. Many participants reported to the examiner that their hearing aid does not “work” with the telephone, and that they either removed the aid or used their unaided ear. This was of some concern because all the participants who reported not using their hearing aid when speaking on the telephone had at least a moderate hearing loss, and some had a severe de- gree of hearing loss. According to data from MarkeTrak V (Kochkin, 2000), one of the main reasons hearing aid owners gave for not using amplification was difficulty using the tele- phone with their hearing aid. The participants in this study could have maximized their use of their hearing aids by im- proving how they use their hearing aids with the telephone.

Many participants also had difficulty cleaning their hear- ing aids. For instance, 90% of the participants who scored below satisfactory on this task did not clean the microphone port, and 32% failed to satisfactorily clean the receiver. Proper maintenance of a hearing instrument is crucial to the proper functioning of the instrument. In fact, the most common hear- ing aid repairs are to replace or clean the receiver due to cerumen buildup, and to replace or clean the microphone due to skin oils and other debris (Block, 2001). Without proper care, a hearing aid may not operate to its fullest potential, which means the user may not hear as clearly as possible.

The thirdmost difficult task for participants on the PHAST was using the noise program/directional microphone. Most participants either were not aware that they had a noise pro- gram or directional microphone or knew it existed but were unable to satisfactorily use it. Understanding speech in noise is one of the primary complaints of individuals with hearing loss. Fortunately, advances in hearing aid technology have improved our ability to help listeners with hearing loss under- stand speech in background noise. However, if listeners are not able to use the technology correctly, they will not benefit from it. According to data from MarkeTrak V (2000), more than 25% of consumers reported that they did not wear their hearing aids because the hearing aids did not help them in noisy situations. Furthermore, many of the consumers wrote that they purchased hearing aids specifically to help them hear in noisy situations. Based on the PHAST results, it is con- ceivable that many of the consumers surveyed inMarkeTrakV had hearing aids with directional microphones but simply were not able to properly switch their hearing aid into the directional mode and maximize the benefit from this feature.

In recent years, “automatic” or “adaptive” hearing aids have been developed that monitor the listening environment and adapt hearing aid parameters (e.g., directionality or t-coil) for different acoustic conditions so that no manual adjust- ments are needed. None of the participants in the current study had automatic hearing aids. However, scoring of the PHAST can be adjusted for individuals with automatic hearing aid features. For example, if the PHASTwere administered to a

client who had a hearing aid with an automatic t-coil, the client would be scored only on correctly positioning the tele- phone in relation to the hearing aid microphone, which is a required skill to properly use the hearing aid with the telephone.

In the future, as automatic hearing aid features become more readily available, the directional microphone and t-coil questions on the PHASTwill need to be modified. Currently, however, automatic hearing aid features are found primar- ily in more expensive midprice to high-end hearing aids. Since a substantial proportion of older hearing aid users are unable to afford expensive hearing devices because of lim- ited financial resources (Johnson, Danhauer, & Krishnamurti, 2000; Meister & von Meidel, 2003), it seems likely that there will continue to be a large number of individuals who use hearing aids that require manual adjustments.

Interestingly, only age was a significant predictor of the participants’ performance on the PHAST. Specifically, older participants did not perform as well on the PHAST as did the younger participants. This is consistent with the finding that elderly users self-report a greater need for ease of hearing aid manipulation than younger hearing aid users (Meister & von Meidel, 2003). It is likely that older participants’ poorer performance is due, in part, to age-related deficits in work- ing memory. That is, older hearing aid users may not be able to process and store information that was presented to them during their hearing aid trial period as well as younger hearing aid users (Salthouse, 1990). Therefore, it may be even more important to use the PHASTwith older clients who may self- report that they have no trouble manipulating their hearing aids. If the PHASTwere included in a client’s annual hearing evaluation/hearing aid check appointment, it could identify items on which the individual needs further instruction and counseling.

Another variable we investigated, hours of hearing aid use per day, did not reach statistical significance (p ≤ .014); however, the participants who performed better on the PHAST tended to use their hearing aids more hours per day than participants who performed poorly on the PHAST. This is consistent with other studies which have reported that a hearing aid user’s ability to manipulate his or her hearing aids is significantly related to the amount of time the person uses the hearing aids (Baumfield & Dillon, 2001; Hickson et al., 1986; Humes, 2006; Sorri et al., 1984).

There were no significant relationships between partici- pants’ PHAST scores and their performance on any of the subjective measures administered in this study. Thus, these clinical hearing aid outcome measures could not predict how individuals would perform on the PHAST. Also, participants were asked on the hearing aid lab questionnaire whether they felt they knew how to use their current hearing aids well. Ninety-six percent of them reported that they did know how to use their hearing aids well, and 88% reported they knew how to clean their hearing aids well. Yet only 48% of participants demonstrated excellent or good performance on the PHAST, and only 38% of participants scored either better than satisfactory or excellent on the PHAST cleaning skill task. Clearly, there is a mismatch between hearing aid users’ perceived ability to manipulate their hearing aids and their actual ability to perform the tasks. In other words, simply asking hearing aid users whether they understand the basic

74 American Journal of Audiology • Vol. 18 • 69–76 • June 2009

skills required to operate and clean their hearing aids could be misleading.

The hearing aid functions on the PHAST are representa- tive of the most basic skills an individual needs to know to use his or her hearing aids correctly (e.g., GN ReSound, 2005; Oticon, 2003; Siemens, 2005). The majority of the participants in this study had more than 5 years of hearing aid experience and wore their instruments for more than 5 hr per day, which would suggest that they are successful hearing aid users. Yet, interestingly, only 18% of the participants in this study scored excellent on the PHAST. The primary rea- son participants in this study did not obtain an overall ex- cellent score on the PHASTwas because they performed less than adequately on the hearing aid cleaning task. Thus, not having a clean hearing aid will likely only affect a person’s use of his or her hearing aid in severe cases, when debris affects the performance of the aid.

Individuals who wear hearing aids without fully under- standing how to use them correctlymay not be receivingmax- imum benefit from the devices. In theworst case scenario, this could result in the hearing aid user rejecting amplification altogether. Therefore, this highlights the importance of di- rectly assessing individuals’ ability to use their hearing aids. The PHAST is an objective tool to evaluate a hearing aid user’s ability to manipulate his or her hearing aid. The PHAST is easy to administer and provides information that is not available from other clinical tests. The results from the PHAST can be used to identify specific hearing aid functions for which a hearing aid user needs further counseling and training.

Acknowledgments This project was supported by funding from the Schneller Grant.

Portions of this article were presented at the 2007 Annual Convention of the American Speech-Language-Hearing Association in Boston, and at the 2007 American Auditory Society meeting in Scottsdale, AZ. Wewould like to thank Sharon Sandridge for her helpful comments on an earlier version of this article.

References American National Standards Institute. (2004). Specifications

for audiometers (ANSI S3.6-2004). New York: Author. Baumfield, A., & Dillon, H. (2001). Factors affecting the use and

perceived benefit of ITE and BTE hearing aids. British Journal of Audiology, 35, 247–258.

Block, M. (2001). Hearing aid repair rates. Retrieved May 23, 2007, from www.audiologyonline.com.

Brooks, D. (1994). Some factors influencing choice of type of hear- ing aid in the UK: Behind-the-ear or in-the-ear. British Journal of Audiology, 23, 3–11.

Cohen, J. (1988). Statistical power analysis for the behavioral sciences (2nd ed.). Hillsdale, NJ: Erlbaum.

Cox, R., & Alexander, G. (1992). Maturation of hearing aid ben- efit: Objective and subjective measurements. Ear and Hearing, 13, 131–141.

Cox, R.M., & Alexander, G. C. (1995). The Abbreviated Profile of Hearing Aid Benefit (APHAB). Ear and Hearing, 16, 176–186.

Cox, R. M., & Alexander, G. C. (1999). Measuring satisfaction with amplification in daily life: The SADL Scale. Ear and Hearing, 20, 306–320.

Cox, R. M., Alexander, G., & Gray, G. (1999). Personality and the subjective assessment of hearing aids. Journal of the Amer- ican Academy of Audiology, 10, 1–13.

Garstecki, D., & Erler, S. (1998). Older adult performance on the communication profile for the hearing impaired. Journal of Speech and Hearing Research, 39, 28–42.

Gatehouse, S. (1994). Components and determinants of hearing aid benefit. Ear and Hearing, 15, 30–49.

Gatehouse, S. (2002). Electronic aids to hearing. British Medical Bulletin, 63, 147–156.

GN ReSound. (2005). User guide: ReSound Metrix mini BTE. Bloomington, MN: Author.

Hickson, L., Hamilton, L., & Orange, S. (1986). Factors associ- ated with hearing aid use. Australian Journal of Audiology, 8, 37–41.

Humes, L. (2006, November). Hearing-aid outcome measures in older adults. Proceedings of the International Conference, A Sound Foundation Through Early Amplification, Chicago.

Hutchinson, K., Duffy, T., & Kelly, J. (2005). How personality types correlate with hearing aid outcome measures. Hearing Journal, 58(7), 28–34.

Johnson, C., Danhauer, J., & Krishnamurti, S. (2000). A holis- tic model for matching high-tech hearing aid features to elderly patients. American Journal of Audiology, 9, 1–12.

Kochkin, S. (1996). MarkeTrak IV: 10-year trends in the hearing aid market—has anything changed? Hearing Journal, 49(1), 23–34.

Kochkin, S. (2000). MarkeTrak V: Why my hearing aids are in the drawer—the consumers’ perspective. Hearing Journal, 53(2), 34–41.

Kochkin, S. (2005). MarkeTrak VII: Customer satisfaction with hearing instruments in the digital age. Hearing Journal, 58(9), 30–37.

Meister, H., & von Meidel, H. (2003). Demands on hearing aid features—special signal processing for elderly users? Interna- tional Journal of Audiology, 42, S58–S62.

National Council on Aging. (1999). The consequences of untreated hearing loss in older persons. Washington, DC: Author.

Oticon. (2003). User instructional brochure: Gaia. Copenhagen, Denmark: Author.

Pfeiffer, E. (1975). Short portable mental health status question- naire for the assessment of organic brain deficit in elderly patients. Journal of the American Geriatric Society, 23, 433–441.

Salthouse, T. A. (1990). Working memory as a processing resource in cognitive aging. Developmental Review, 10, 101–124.

Shrout, P., & Fleiss, J. (1979). Intraclass correlations: Uses in assessing rater reliability. Psychological Bulletin, 86, 420–428.

Siemens. (2005). General hearing instrument information. Piscataway, NJ: Author.

Sorri, M., Luotonen, M., & Laitakari, K. (1984). Use and non- use of hearing aids. British Journal of Audiology, 18, 169–172.

Spector, P. (1992). Summated rating scale construction: An intro- duction. Newbury Park, CA: Sage.

Valente, M., Fabry, D., Potts, L., & Sandlin, R. (1998). Com- paring the performance of the Widex SENSO digital hearing aid with analog hearing aids. Journal of the American Academy of Audiology, 9, 342–360.

Received July 16, 2008 Accepted March 30, 2009 DOI: 10.1044/1059-0889(2009/08-0022)

Contact author: Jamie L. Desjardins, Department of Communication Sciences and Disorders, Syracuse University, 805 S. Crouse Avenue, Syracuse, NY 13244. E-mail: [email protected].

Desjardins & Doherty: Correct Use of Hearing Aids 75

Appendix

The Eight Practical Hearing Aid Skill Tasks on the PHAST

Each task is scored on a 5-point Likert scale in which 4 = excellent, 3 = better than satisfactory, 2 = satisfactory, 1= poor, and 0 = cannot perform.

1. Remove your hearing aid(s). a) grasping aid/dexterity b) removal of aid from ear

2. Open the battery door. a) locate the door b) open the door

3. Change your hearing aid battery. a) remove old battery b) insert new battery

4. Show me how you clean your hearing aid. a) sound bore b) microphone c) vent

5. Put your hearing aid(s) back in your ear(s). a) grasping aid/dexterity b) placement in ear

6. Turn up the volume of your hearing aid(s). 7. Show me how you use the telephone with your hearing aid(s). (Hand phone to client.)

a) correct use of program/t-coil switch b) placement of phone in relation to hearing aid

8. Show me how you use your noise program/directional microphone.

76 American Journal of Audiology • Vol. 18 • 69–76 • June 2009