User’s perspective of benefits of frequency-lowering hearing aids and electric acoustic stimulation cochlear implants in daily life

Abstract

BACKGROUND:

Different technological alternatives are nowadays offered to persons with a severe-to-profound high-frequency hearing loss (HFHL). However, benefits of those technologies are still not clear.

OBJECTIVE:

To explore the benefits provided by frequency-compression (FC) or frequency-transposition (FT) hearing aids (HAs), and the electric acoustic stimulation (EAS) cochlear implant, from the perspective of users with a HFHL.

METHODS:

A qualitative case study research design was selected. Ten adults with a HFHL who participated in a previous FC, FT and EAS trial were enrolled. Individual semi-structured interviews were conducted. Participants were questioned about their experience with each technology. Data were analyzed using a qualitative content analysis.

RESULTS:

Participants reported better speech understanding in quiet and noisy situations, plus improved high-frequency sound detection with both HAs. Some participants mentioned lower levels of listening effort and fatigue and an improvement in self-confidence, which led to increased social participation. Most participants preferred FC or FT to their own HAs. The participant who received an EAS implant reported better performances with this technology.

CONCLUSIONS:

From the participants’ perspective, the three technologies can deliver greater benefits than conventional amplification for people with a severe-to-profound HFHL, but the EAS implant appears as potentially more beneficial than both HAs.

Keywords

High-frequency hearing loss hearing aids frequency-lowering cochlear implants electric acoustic stimulation qualitative research

1. Introduction

Various technological alternatives to conventional hearing aids are nowadays offered to people living with a sensorineural severe-to-profound high-frequencyhearing loss (HFHL), such as frequency-lowering (FL) hearing aids and cochlear implants, whether in conventional electrical or electric acoustic stimulation (EAS) [1, 2]. Previous studies have shown the potential of different types of frequency-lowering, such as frequency-compression (FC) or frequency-transposi-tion (FT) hearing aids, to improve speech perception for this population. Reported group mean improvements to a variety of speech perception tasks realized in laboratories with FC or FT hearing aids are generally ranging from 5 to 20% [3, 4, 5, 6, 7, 8, 9], in comparison with conventional amplification. The group mean gain in speech perception with an EAS implant appears to be greater, and was reported to range between 27 to 65% [10, 11, 12, 13, 14, 15]. However, the benefits obtained with those technologies in real life are still not clear. Also, there are some differences in participants’ hearing levels between groups of studies which assessed the aforementioned hearing technologies [16]; this may introduce a bias in the comparisons that could be done between the benefits offered by each of those technologies.

The benefit offered by hearing technologies isknown to be multidimensional [17, 18, 19, 20, 21]. It is not limited to speech perception, but also includes the reduction of experienced hearing disabilities and limitations in social participation, and the improvement of quality of life. Moreover, it is dependent of diverse personal factors such as expectation, motivation, daily device’s use, personal beliefs or values. For example, the benefit gained from a hearing aid by a given patient may not be optimal if this person does not routinely wear the device or if perceived functional limitations prior to the fitting were not sufficiently important, even if the prescribed hearing aid allows for a clinically significant improvement in speech recognition. Then, when assessing the effectiveness of hearing technologies, it is essential to consider not only the effect of the technology on speech recognition outcomes, but also on other related dimensions, which may help to better circumscribe the real benefit of the technology in daily life.

Few studies have assessed the benefits of FL hearing aids and of the EAS implant for people with a severe-to-profound HFHL. In these studies, authors have sometime used standardized questionnaires or informal interviewing to complement quantitative measures on speech perception. In studies that addressed FC hearing aid benefit [22, 23, 24, 25, 26], the authors did not report significant improvements with the use of FC in comparison with conventional hearing aids at a group level, but benefits were reported for some individuals. Nyffeler [24] presented an improved median benefit for 11 adult subjects with the use of FC hearing aids, but the significance of those results is not confirmed by statistical analysis. Simpson et al. [26] have shown a gain for some individuals, but also a decrease in benefit for other participants. Those authors outlined that the use of FC allowed for a better speech understanding, sound quality and environmental and speech sound detection for some individuals, but also increased listening discomfort; Parent et al. [25] also mentioned a reduced mental effort for one participant with the use of FC.

Authors who studied FT hearing aid benefit for people with a severe-to-profound HFHL reported similar results. A better environmental and speech sound detection for individuals was mentioned in some studies [27, 28, 29]. Smith et al. [9] reported FT non-auditory benefits for half of their participants, such as a better self-confidence, self-esteem, and reaction to their names; they also mentioned that participants were formulating less repetition requests when using FT hearing aids. Also, Kuk et al. [30] reported on one participant who mentioned that listening with FT requires less effort. However, the use of FT appeared as possibly deleterious for speech understanding in noise [31].

Other studies have assessed the benefit of the EAS implant for people with a severe-to-profound HFHL with standardized questionnaires. Authors have reported improvements to the Abbreviated Profile of Hearing Aid Benefit (APHAB) global score with the use of EAS in comparison with conventional hearing aids, ranging from 30 to 70% [11, 32, 33], and between 14 and 47% on the different subscales of the questionnaire [34, 35, 36]. Other authors evaluated the benefit of EAS with the Speech, Spatial, and Qualities of Hearing (SSQ) scale, and showed improvements ranging from 9 to 22% on the questionnaire subscales [12, 14]. In those studies, no specific dimensions of benefit were mentioned.

Thus, while some authors have shown an interest in exploring the real-life benefit provided by FL hearing aids and the EAS implant to people with a severe-to-profound HFHL, this outcome has not been extensively assessed and does not appear to be well defined yet. Moreover, no study compared the two technologies directly with each other; the benefit of each technology was assessed separately and compared with conventional hearing aids.

In a previous project [37], where the clinical effectiveness of FC, FT and EAS to improve speech perception for hearing-impaired people was explored, 10 adults with a severe-to-profound HFHL successively tried FC and FT hearing aids, following an ABAC single-subject design; one of the participants also received an EAS implant at the end of the trial. Results suggested the superiority of the EAS implant over conventional, FC and FT hearing aids to enhance speech recognition for the included participants, with an improvement of up to 41%, which was found to be comparable to a cohort of 10 other EAS users. A small but significant effect was also found with FC and FT hearing aids in speech recognition tasks for five participants, with a maximum measured gain of 9%. Other subjects experienced either no gain or some degradation in speech recognition when using a FL algorithm. Interestingly, eight participants reported significant benefits with the use of FL hearing aids to the Glasgow Hearing Aid Benefit Profile (GHABP) and APHAB questionnaires, even if their speech recognition abilities were unchanged or negatively affected by the use of FC or FT. In the context where the benefits of FC, FT and EAS are not well defined in the scientific literature yet, we decided to expand our project to further explore the benefits experienced by the participants with FC or FT hearing aids and the EAS implant in daily life from their unique perspective.

2. Methods

2.1 Design

In order to meet the research objective, a qualitative case study research design with semi-structured interviews was selected [38, 39].

2.2 Participants and context

Participants are 10 adults aged between 52 and 74 years old. They all presented with a bilateral sensorineural severe-to-profound HFHL with aidable residual hearing in low frequencies. Enrolled participants were all subjects who participated in the Hotton and Bergeron study [37]. Participants experienced FC (Phonak Naída Q70 SP or UP, or Naída III SP; Stäfa, Switzerland) and FT (Widex Dream 440 Fashion, Fusion P or Fusion HP; Lynge, Denmark) hearing aids following an ABAC single-subject design. A four to six-week baseline was first completed with their own hearing aids (phase A1), followed by an eight-week real-life trial with one FL device (phase B). Then, a second baseline of four weeks was repeated with their own hearing aids (phase A2). Finally, subjects tried a second FL hearing aid for eight weeks (phase C). Phases B and C were counterbalanced between subjects. After those trials, subject S3 also received a cochlear implant (Med-El Concerto Mi1000 PIN with a Flex 24 electrode; Innsbruck, Austria) in the right ear; residual hearing in low frequencies was sufficiently well preserved after surgery to allow for the use of a Sonnet EAS speech processor. Experimental protocol was then extended to an ABACD design for this participant. Repeated measures of speech recognition were done each week, for the complete duration of the trial, to establish the variance in performance for each treatment. In addition to formal speech recognition assessments and completion of standardized questionnaires, individual semi-structured interviews were conducted at the end of the trial; this is the focus of the present study.

All participants had a previous experience with conventional hearing aids of at least nine years. At the time of the interview, all subjects had an experience of at least eight weeks with each FL device; the experience of the participant who received an EAS implant was 12 weeks with this technology. Detailed sociodemographic data are presented in Table 1. Complete details on participants’ audiometric data and on hearing technologies fittings are presented in the Hotton and Bergeron paper [37].

Table 1
Sociodemographic characteristics of the participants

Characteristics	Number of participants
Age
50–59 years	4
60–69 years	3
70–79 years	3
Gender
Male	4
Female	6
Degree of hearing loss (best ear
average 500–4000 Hz)
70–79 dB HL	1
80–89 dB HL	4
90–99 dB HL	3
100–109 dB HL	2
Hearing loss duration
10–19 years	1
20–29 years	0
30–39 years	3
40–49 years	3
50–59 years	2
60–69 years	1
Previous experience with hearing aids
0–9 years	1
10–19 years	2
20–29 years	3
30–39 years	3
40–49 years	0
50–59 years	1
Unilateral fitting	1
Bilateral fitting	9
Own hearing aid model (no FL
activated in any case)
Oticon Vigo Connect P13	2
Phonak Certéna Art M	1
Phonak Naída III SP	2
Phonak Naída III UP	1
Starkey Providence 8	1
Unitron Next 16 HP	1
Unitron Latitude 8 Dir HP	1
Widex Mind 220 M2 19	1
Education
Less than high-school	1
High-school	5
College or university	4
Living situation
Alone	3
With spouse or partner	6
With spouse or partner and children	1
First language
Canadian French	9
Canadian English	1

Note. dB $=$ Decibel; FL $=$ Frequency-lowering; HL $=$ Hearing level; Hz $=$ Hertz.

The research project has been approved by ethics boards of the Centre Hospitalier Universitaire (CHU) de Québec (#2014-1860, C13-12-1860), of the Centre Intégré Universitaire de Santé et de Services Sociaux (CIUSSS) de la Capitale-Nationale (#2013-328) and of the Centre de Recherche Interdisciplinaire en Réadaptation du Montréal Métropolitain (CRIR, #CRIR-846-0513). Information and explanations about the interviews’ conduct were given to the participants, and they had to sign a consent form prior to the beginning of the interview. Subjects received a financial compensation of 10 CAD for their participation in the interview.

2.3 Procedures

Participants were invited to a semi-structured one-on-one interview [39] to collect their comments and perspectives on the benefits obtained with each technology. Interviews were conducted by the first author, either at the CIUSSS de la Capitale-Nationale in Québec City ( $N=6$ ) or at the Audiology Centre-West clinic in Montréal ( $N=4$ ), depending on the region of residence of the participant. Each subject was met once, within two weeks after the end of FL hearing aid trials. Interviews were audio recorded. At the time of the interviews, participants were wearing their own conventional hearing aids, as they had to give back FC and FT hearing aid loaners to the research team at the end of the trials. Interviews lasted around 60 minutes, and followed a topic guide that was prepared in advance and pre-tested with the first two subjects. Participants were questioned on the perceived changes, advantages or disadvantages experienced with each assessed hearing technology, and their preference for one technology over the others. A second interview was realized with Subject S3 four months following implantation (three months following the activation of the EAS implant) to collect data on the benefits of the EAS implant. For that second interview, a written format was used because of the impossibility of the participant to come to the clinic for the completion of the interview. The topic guide was sent by email to Subject S3, who responded in writing.

2.4 Analyses

Audio recordings were transcribed into text files, word for word (verbatim). Verbatim was analyzed following the principles of qualitative content analysis, using an inductive approach [40, 41, 42, 43]. Content areas were defined as text samples where participants described the effects of the assessed hearing technologies in their real life, whether those effects were positive or negative, and related to auditory perception or not. Data extracted from those content areas were divided into meaning units, coded and classified by subcategories. Then, induced subcategories were compiled according to five categories, which corresponded to the topics included in the interview guide (perceived positive or negative changes in auditory perception abilities, non-auditory advantages or disadvantages experienced with each technology, and technological preferences). The software QDA Miner 4.1.33 (Provalis Research) was used to organize data and to support the coding of meaning units.

An iterative process was followed to ensure a rigorous analysis of the data. The analysis was compared to the original interview recordings and verbatim at many times during the process to avoid transcription errors and validate the coding. Subcategory extraction, classification into categories and data interpretation was done by the first author and then validated by the second author; when a disagreement occurred, it was discussed and solved by mutual consensus. This was done to achieve a better trustworthiness of the analysis [40].

3. Results

Data show that the majority of the participants experienced benefits with FL hearing aids, to the point that they would have kept the FL hearing aids at the end of the trial if it were possible. The subject who received an EAS implant also found the performance of FL better than the one of her own hearing aids, but still reported better benefits with the EAS implant. One participant did not report any advantage with the use of FL hearing aids and preferred his own instruments. A list of the extracted categories and subcategories is shown in Table 2; descriptions are presented below.

Table 2
List of the extracted categories and subcategories

Extracted categories and subcategories
Category 1: Positive changes in auditory perception abilities
	Better listening in quiet
	Better listening in noise
	Better listening in general
	Better environmental sound perception
	Better speech sounds perception
	Better listening in a group conversation
	Better listening to music
	Better listening comfort
	Better loudness
	Better sound quality
	Better listening to a movie at the cinema
	Better listening to the telephone
	Better listening in reverberation
	Better listening to the television
Category 2: Negative changes in auditory perception abilities
	Environmental sounds too loud
	Increased listening discomfort
	Increased high-frequency speech sound perception
	annoying
	More feedback problems
	More difficulties listening in noise
	More difficulties listening to the telephone
	More echo problems
	Loudness too much increased
	More autophonation problems
	Worse listening in general
	More difficulties listening in quiet
	More difficulties listening to music
	More difficulties listening to the television
	More difficulties listening in the car
	Increased wind noise perception
Category 3: Non-auditory advantages
	Reduced need to rely on lip reading
	Reduced listening effort
	Reduced general fatigue
	Better self-confidence
	Reduced repetition requests
	Increased participation to social activities
	Better voice control
	Increased feeling of being part of the world
Category 4: Non-auditory disadvantages
	Increased general fatigue
Category 5: Participants’ technological preferences
	Preference for frequency compression hearing aids
	Preference for frequency transposition hearing aids
	Preference for the EAS implant
	Preference for conventional hearing aids
	Preference for frequency compression and transposition
	hearing aids

Note. EAS: Electric-acoustic stimulation.

3.1 Category 1: Positive changes in auditory perception abilities

The most commonly reported positive changes in auditory perception with the assessed hearing technologies in comparison with own conventional hearing aids were a better listening in quiet and in noise, a better listening in general, and also a better environmental sound perception. Those advantages were mentioned by the majority of the participants and were apparently not specific to a given hearing technology, with the exception of the EAS implant, which was seen as superior to conventional, FC and FT hearing aids by subject S3. Improvements for listening in quiet with FC and FT hearing aids have been described in the following terms.

I hear better with the new hearing aids. My wife told me that with my own hearing aids, sometimes she talks to me and I don’t answer, but with the new hearing aids, I can hear her. It would not be the case in noise, it happens at home, in everyday life. She was talking to me from the kitchen to the living room, and I could hear her (S12, male, 60). In conversation, I would have heard people speaking more clearly, like at work, you know in a work environment, because it is where I spend most of my time. So, I have meetings quite a bit, I have a lot of meetings with my staff. We even have like video conferencing, which is very hard to hear, and I would say even in the video conferencing, a slight improvement for sure, I can’t say how much percent but it was definitely better (S6, female, 56).

Many participants cited the restaurant situation to illustrate the improvement for listening in noise with FC and FT hearing aids; this situation appears to be quite significant in real-life.

Remarkably, with the first trial hearing aids at the restaurant, I would never forget that, I was able to hear the third person seated at my table’s side, in a very noisy restaurant, noise was coming from everywhere, […] it has never happened to me before. My wife was seated at the table’s corner with me, that is very hard with my own hearing aids, even with directional microphones. And then, I was able to hear the third person, some words, that left a mark on me. In so much noise (S10, male, 52).

With the EAS implant in noise, subject S3 talked about her experience at the supermarket and also at the restaurant.

For conversation with another person in a very noisy environment, I’m able to follow the conversation with the person in front of me, but ambient noises are very annoying, particularly in a restaurant with high ceilings. With hearing aids, that was not possible (S3, female, 52). At the supermarket, I’m able to hear the cashier as well as the bakery attendant, which was not the case with hearing aids (S3, female, 52).

Environmental sound perception has also been reported to be improved with FC, FT and EAS. Participants mentioned many different environmental sounds that were detected or perceived louder, such as the microwave oven or cooking range alarm, car noises (flasher, mechanic noises or radio), bird songs, rustling leaves, fire alarm, telephone ringing, and the buzzer sound on TV shows. Some subjects commented on a better perception of speech sounds (sharper and clearer words, better perception of fricatives), and of music instruments, such as the piccolo, high-hat, cymbals and small percussions. Then, assessed technologies appear to provide some benefit not only for speech perception, but also for the perception of environmental sounds encountered in everyday life.

3.2 Category 2: Negative changes in auditory perception abilities

The loudness of environmental sounds and a general listening discomfort were the negative changes with FC, FT and EAS that were mentioned more often by participants. Many environmental sounds that were badly or not at all heard with conventional hearing aids have been reported to be annoying with the use of the assessed technologies, such as running water noises (tap water or toilet’s flush), the refrigerator, brushing teeth, door banging, dish washing, traffic noise when walking on the street, and kids’ voices and cries. Those difficulties were attributed more frequently to FT than to FC. Subject S9 described her experience with the perception of ambient noises in the car as followed.

I call it a useless noise, but the funny thing is, everybody hears that sound. When I drive my car, […] all I hear now is the noises created by the car, tires… I mean, I put the radio on and I can’t hear nothing. It’s really a useless noise. I can’t hear anything else (S9, female, 59).

Some subjects reported that annoyance due to the perception of environmental sounds was worse during the first times with trial hearing aids. Subject S8 philosophized:

Yes, it is annoying, but as my wife once said to me, hearing persons also hear those sounds, it’s correct. Then you get used to it (S8, male, 68).

The general listening discomfort that was reported by half of the participants is seen as the price to pay for being able to hear better, as expressed by subject S6.

It came at a cost. […] I could hear better, but unpleasant, you know. It’s like, great, I can hear better but it hurts almost, it’s unpleasant. It was too loud, it was difficult to sustain that kind of loudness in my head all the time (S6, female, 56).

With the EAS implant, subject S3 reported that some sounds, which were not detected with hearing aids, are now perceived, but uncomfortable to hear (car tires on a wet road, toilet’s flush and kids’ voices and cries). She also mentioned problems in listening to the telephone and to music:

High-frequency notes on the piano are horrible with the implant. In general, music is horrible with the implant, I have difficulty to recognize the melody. With hearing aids, there was no special difficulty when listening to music, except for high-frequency sounds which I wasn’t able to hear (S3, female, 52).

Noteworthy, some participants mentioned that listening in noise was worse with the use of FT hearing aids. Feedback problems were reported by some participants with the FT hearing aid and the EAS implant. Echo was also mentioned by a few participants with FC and FT hearing aids.

3.3 Category 3: Non-auditory advantages

In addition to changes in auditory perception abilities, participants reported advantages of FC, FT and EAS that were related to other non-auditory aspects of the use of the assessed hearing technologies. Participants talked about changes in their behaviors caused by the use of FC and FT hearing aids. They mentioned that with those technologies, they were less prompt to rely on lip reading to support speech understanding, and that they had to make less effort to be able to follow a conversation, which led to the experience of less fatigue by the end of the day. Subject S9 talked about listening effort and fatigue, and said that with the use of FL hearing aids, she developed a better self-confidence, allowing her to participate in more social activities:

I’m less tired because I don’t have to concentrate so much. That’s a big improvement. And because it’s less tiring for me to be with people, then I was more tempted, it’s not that I did many more things, but I was going out for a longer period of time, and still I was less tired. That was really very positive (S9, female, 59). What it did to me is, I came out of my shell. Hey, I can hear this, I had the impression to hear better. […] So, I think I gained more confidence, more self-esteem. Then I was able to go out for longer periods of time. I even didn’t recognize myself (S9, female, 59).

A participant also mentioned that he had to ask the interlocutor to repeat less often and that he had a better control over his own voice with the use of FL hearing aids. The participant who received an EAS implant also said that with this technology, she had the feeling of being part of the world again.

3.4 Category 4: Non-auditory disadvantages

While two participants reported that the use of FL hearing aids helped to reduce fatigue, one inversely reported that the FT hearing aid has induced more fatigue. For this participant, increased fatigue was linked to the sound of the hearing aid, that was richer in high frequencies; with time, this negative effect appeared to vanish. Subject S12 expressed his point of view as follows:

At the end of the day, I was more tired. It’s because of the “sh” sounds, it’s clearer and more offensive in the long run. But I think I have a very strong capacity to adapt, and by the end of the trial, I didn’t notice it anymore (S12, male, 60).

3.5 Category 5: Participants’ technological preferences

When questioned about their preference for one technology over the others, a majority of participants chose the FC hearing aids, a minority the FT hearing aids, and one her own hearing aids. Reasons for choosing the FC hearing aid were an easier adaptation, a better sound quality, less aggressive, more natural and less echo, a better general comfort, a better listening in noise and in general, and an easier manipulation, in comparison with FT. Reasons to choose FT hearing aid were an easier adaptation, a better general comfort, a better listening in general, and an easier manipulation, in comparison with FC. The participant who chose to keep her own hearing aids reported a better listening in general and in noise, and a better value for money, in comparison with FC and FT hearing aids. One participant would have preferred a FL hearing aid, but was not able to choose between FC and FT. This participant reported similar performances and benefits with FC and FT hearing aids. She explained that her choice would probably depend on the price and included options with each device.

The participant with the EAS implant would have preferred FC in comparison with her own hearing aids, but she reported better benefits, better speech perception and sound detection with the EAS implant. As she said, she does not regret her choice to go for implantation:

If I could do it all over again, I would make the same choice. I would choose cochlear implantation. With the implant, what is fantastic is that I can hear ambient noises. With the hearing aids, those sounds weren’t audible at all. Bird songs, the wind in the trees, the door closing, small noises that we do when eating, in short, all those little everyday noises that I can hear now. It’s like being part of the world again (S3, female, 52).

4. Discussion

The objective of this qualitative research project was to further explore the benefits experienced with the use of FC or FT hearing aids and of the EAS implant in daily life, from the perspective of hearing-impaired adults presenting a specific severe-to-profound high-frequency hearing loss. Results show that, from the participants’ perspective, those technologies delivered greater benefits than conventional amplification for speech understanding, in a variety of quiet and noisy listening situations. The assessed technologies allowed for better environmental sound perception, even for lower levels of listening effort and fatigue, and improvement in self-confidence which led to increased social participation for some participants. Technologies were often judged easier to manipulate in many ways. Still, the participant who received an EAS implant reported better benefits with this technology. Those results suggest that the improvements in the hearing benefit with FL hearing aids and the EAS implant are significant from the perspective of the participants, which is in line with the conclusions of the preceding project [37].

In this study, the participant who received an EAS implant (S3) reported greater benefits with FL hearing aids and EAS implant than with conventional hearing aids. She also judged the EAS implant as globally more beneficial than FL, because of a better speech perception and environmental sound detection with the EAS implant. This result may have been influenced by the degree of hearing loss of the subject, or by the FL settings that were used for her. Participant S3 was one of the subjects with the greatest hearing loss between 1 and 2 kHz, and presented with cochlear dead regions in the same frequency range. As for other participants with a comparable hearing loss in mid frequencies (ex. S8 and S12), speech recognition of participant S3 did not improve very much with FL [37]; in fact, those participants got the most detrimental effects with FL. For them, the cochlear damage may have been too severe in the FL destination band, which may have limited benefits from FL hearing aids. Also, in order to improve effectively high-frequency audibility, we had to use stronger FL settings for those participants. This could have caused undesired distortion that may have counteracted the potential benefits of the algorithms. Thus, if the hearing loss of the participant who received an EAS implant would have been less severe, the balance between the benefits obtained with FL and EAS implant may have been different.

Participant S3 also mentioned more listening discomfort and more difficulties to listen to the telephone and to music with the EAS implant, in comparison with hearing aid technologies. However, her experience with the use of the EAS implant was limited to 12 weeks at the time of data collection, which is quite short, as auditory perception abilities are known to improve years after implantation [44, 45]. This may have had an impact in reducing the benefit gained from the EAS implant.

The auditory benefits experienced with FL by the participants of this study are comparable to those reported in previously published studies. However, on the non-auditory benefit side, less listening effort and fatigue with FL hearing aids for some participants, supporting an improvement in self-confidence and social participation, follows the newest trends in hearing research. Kuk et al. [30] already mentioned one participant who reported that listening with a FT hearing aid required less effort; Parent et al. [25] mentioned another person who felt that listening with a FC hearing aid was draining less mental effort than with a conventional hearing aid. But the subsequent consequences of these improvements were not addressed in either of these studies.

A majority of participants mentioned that the improved benefits with FL hearing aids came at the cost of an increased listening discomfort, as better heard sounds were often perceived as too loud and annoying. This also has been reported in earlier studies on FC and FT [23, 25, 31]. The listening discomfort observed in this study have been attributed to both FC and FT hearing aids by participants, but listening with FT was more often mentioned to be more uncomfortable than FC. Moreover, listening in noise was reported to be worse with FT than with FC hearing aids by few participants. This suggests that FT hearing aids may be less appropriate than FC hearing aids for people with a severe-to-profound high-frequency hearing loss.

The apparent greater listening discomfort and difficulties in noise with FT hearing aids may have influenced participants to prefer FC hearing aids more often, as many different aspects of listening comfort and a better speech listening in noise were mentioned as reasons for choosing FC over FT hearing aids. However, they were not the only factors which played a role in this choice. The ease of manipulation of the hearing technology was also commonly reported by participants when making a choice between FC and FT hearing aids. This factor is not specifically related to FL, as it represents a more global characteristic of the technology. Thus, it appears that participants did not rely solely on the listening appreciation of the assessed hearing technologies to make their final choice; they also considered other aspects of hearing technologies not related to FL to build a bigger picture from which they took their decision.

Therefore, participants’ choice may not reflect a superiority of FC over FT that is specific to the FL algorithm, but a more global effect of a hearing aid technology which include FC among other features. The same analysis could be done for data pertaining to the participants’ perspectives on the greater benefits obtained from FL when compared to their conventional hearing aids. In this clinical research, participants compared their personal experiences with FC, FT and conventional hearing aids that were already available on the market, from different manufacturers; all assessed technologies had their own technical specificities (ex. processors, microphones amplitude compression) that might have influenced the perceived benefit. Moreover, the conventional hearing aids owned by the participants are based on older technologies than the FL hearing aids used in this trial, which may be another factor that led participants to prefer FL hearing aids. This idea is reinforced by the fact that, in the Hotton and Bergeron previous study [37], the greatest part of the measured effects of FL hearing aids on speech recognition, in comparison with conventional amplification, could not be attributed specifically to the activation of FL. This is an important limitation of this study. More research is needed to better isolate the benefit of FL algorithms from the effects of other technical components of hearing aids.

In the Hotton and Bergeron previous study [37], small but statistically significant effects of up to 9% were found with FC and FT hearing aids in speech recognition tasks for some participants, in comparison with conventional amplification. In many cases, these effects were so small that, in standard clinical settings, such an improvement in speech recognition abilities for a given patient would probably have passed unnoticed or would have been declared not significant. Standardized questionnaires were used to support the significance of the effects measured with speech recognition tools. In the present study, the additional use of qualitative interviews helped to further demonstrate that small improvements in speech recognition may result in a significant benefit in real-life, from the participants’ perspective. This supports the use of a more global approach when assessing benefits of hearing technologies. Researchers and clinicians should consider not to rely entirely on speech perception measures, but to also use data from complementary sources, such as interviews and standardized questionnaires.

4.1 Study limitations

Some limitations of this study have been discussed above, such as the fact that experienced benefits with, and preferences for, trial hearing aids may not reflect a specific effect of FL, and the severity of hearing loss and short experience with the implant for the EAS participant that may have limited the benefits of the assessed technologies for this participant, thus possibly affecting the balance between the benefits of FL versus EAS. It is also important to highlight that this study included a small number of participants, particularly for the EAS implant. This may have limited the diversity of collected data. Then, the picture of benefits of FL hearing aids and EAS implant drawn from collected data may not be complete. But still, as FC, FT and EAS are basically hearing technologies, it could have been expected that the benefits derived from the use of those devices in comparison with conventional amplification would fall inside known dimensions of hearing technology benefit, which was the case in this study. Participants reported on a wide range of positive and negative effects following the use of the assessed technologies on a variety of dimensions, such as speech perception, non-speech auditory perception, functional disabilities and social participation. Thus, the inclusion of more participants would probably not have led to the emergence of more categories. This should be explored further in future research.

Finally, the variety of data collected about the benefits of the EAS implant may also have been limited by the use of a written format interview. A standard in-person one-on-one interview would have been preferable and may have led to a more spontaneous and richer content. When such an interview is not possible, other alternatives than a written format interview should be considered, such as a telephone or an Internet-based videoconference call; a visit at the participant’s home or workplace by a member of the research team would also represent another viable option.

5. Conclusions

From the participants’ perspective, FC and FT hearing aids and EAS implant can deliver greater benefits in real-life than conventional amplification for people with a severe-to-profound HFHL. The EAS implant appears as potentially more beneficial than both hearing aids, but is the costliest and most invasive alternative. In this context, and considering the potential risks and high costs related to cochlear implantation, trials with frequency-lowering hearing aids should be considered on an individual basis prior to implantation.

Data collected with semi-structured interviewshelped to demonstrate the importance of the benefit of FC and FT hearing aids, and evidenced that small effects as assessed with traditional speech recognition measures can be significant from the perspective of the patient. This calls for the use of a more global approach when assessing benefits of hearing technologies. For this purpose, researchers and clinicians should consider not to rely entirely on speech measures, but to use a variety of different data sources.

Footnotes

Conflict of interest

The first author received doctoral training awards from Fonds de recherche du Québec en santé (FRQ-S), Centre Intégré Universitaire de Santé et de Services Sociaux (CIUSSS) de la Capitale-Nationale, and CIRRIS. First author also received research funding from CIUSSS de la Capitale-Nationale and CIRRIS. Phonak Canada and Widex Canada provided hearing aid loaners at no cost for the duration of the trial. The authors have no other source of potential, real, or perceived conflicts of interest to declare.

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User’s perspective of benefits of frequency-lowering hearing aids and electric acoustic stimulation cochlear implants in daily life

Abstract

BACKGROUND:

OBJECTIVE:

METHODS:

RESULTS:

CONCLUSIONS:

Keywords

1. Introduction

2. Methods

2.1 Design

2.2 Participants and context

Table 1 Sociodemographic characteristics of the participants

2.4 Analyses

3. Results

Table 2 List of the extracted categories and subcategories

3.2 Category 2: Negative changes in auditory perception abilities

3.3 Category 3: Non-auditory advantages

3.4 Category 4: Non-auditory disadvantages

3.5 Category 5: Participants’ technological preferences

4. Discussion

4.1 Study limitations

5. Conclusions

Footnotes

Conflict of interest

References

Table 1
Sociodemographic characteristics of the participants

Table 2
List of the extracted categories and subcategories