All participants signed an informed consent form and underwent an evaluation consisted of six steps, described as follows:

Step 1: Initial interview

Participants answered open-set questions regarding hearing aid use:

• a.

  “Do you use your hearing aids? Do you have any problem?”

• b.

  “Do you usually wear both hearing aids (bilateral), only one (unilateral) or none of them?”

• c.

  “What is the main reason for not wearing your hearing aids?”

• d.

  “Approximately how many hours per day do you use your hearing aids?”

• e.

  “Have you made some kind of follow-up (private hearing care center or hearing care services of the public health care system - SUS) during this year using your hearing aids?”

Step 2: SADL™ questionnaire

Each subject answered the SADL™ items as an interview with the researcher, which allowed explanations about the doubts according to their difficulties. Considering that all subjects had hearing aids provided by public resources and not purchased, item 14 (“The cost of the hearing aids seems reasonable?”) was used in order to assess satisfaction regarding costs of batteries and maintenance of hearing aids, unlike the original proposal3.

Step 3: Visual inspection of external auditory canal, to verify the presence of earwax blocking the ear canal.

Step 4: Pure tone audiometry, to assess possible changes in hearing thresholds that could influence hearing aid fitting.

Step 5: Earmold check, to analyze integrity and quality and factors that may cause physical discomfort.

Step 6: Hearing aid's sound check with stethoscope, to verify quality of amplification.

All orientations and suggested interventions were registered and classified as major or minor6 after each assessment.

Data were analyzed using descriptive statistics.

The analysis of hearing aids use considered three aspects: mode of hearing aid use (bilateral, unilateral or none), reasons for non-use of hearing aids and hours using hearing aids.

Table 1 shows the results for mode of hearing aid use after one year.

The analysis of reasons for non-use of hearing aids regarding users who were not using one or none of them is at Table 2.

Regarding to hours of use, the average was 8.6 hours per day, minimum of 0 hours per day and maximum of 18 hours per day; 60.5% reported to wear their hearing aids for eight hours or more and 13% were not wearing them at all.

Table 3 shows data related to the interventions6 needed by hearing aid users after one year.

Major interventions6 were necessary for 81 hearing aid users and 118 needed only minor interventions6. Only one subject did not need any kind of intervention.

Users who kept wearing their hearing aids bilaterally or unilaterally answered SADL™ questionnaire. Results were analyzed considering Global Satisfaction and subscales: Positive Effects, Negative Features, Service and Costs and Personal Image, as seen in Table 4.

Although hearing aid non-use rates vary in literature, the rate of 13% of non-use observed in the present study is higher than 3% seen in an Australian study13, 3.1% from Switzerland14 and 12.4% from United States7. On the other hand, it is lower than 57% from a British study8, 25% from Finland15 and 32.26% seen in hearing aid users from other state of Brazil9. The different criteria used for sample selection of these studies, such as, age groups, period using hearing aids, form of acquisition (purchased, partially or totally funded hearing aids), may have contributed to the variety of non-use rates seen in literature. Further investigations about this topic should use standardized criteria to improve data comparability between different studies.

As seen in Table 1, most of users from this study kept using hearing aids bilaterally, in accordance with recommendations given during fitting process1,2.

In cases of unilateral or no use of hearing aids, the subjects were interviewed about the reason to abandon use, choosing only one main argument. As noted in Table 2, the main reasons stated were: “sound discomfort” (25.5%), “manual dexterity” (14.9%) and “poor benefit” (12.8%), among others. The problems stated by the users could be solved with effective periodical follow-ups, with adjustments in gain and/or device programming, physical adjustments, electroacoustical circuit inspection and cleaning, and by use instructions and advising1,2,6,8. These problems differ from literature findings regarding most recurrent reasons for non-use of hearing aids, which were: poor hearing benefit, non-acceptance of hearing loss or refusal to use a hearing aid, sound or physical discomfort, unattended expectations, stigma or aesthetic factors and financial restrictions4,7–9,14,16–20. Most of the problems indicated by literature are not due to necessity of adjustments or repair of hearing aids, but to subjective factors to users, which depend on the users themselves to be solved.

This fact suggests the necessity to improve long-term follow-up system of publicly-funded health services and users' access to follow-ups appointments, since 32% did not make any kind of follow-up in the first year of hearing aid use, differently from what is proposed in guidelines for audiology services1,2,21,22. The lack of orientation and/or necessary interventions tend to cause reduction in hearing aid use, benefit and satisfaction over time4,6,23,24. Thereby, it is reasonable to question if necessities of Brazilian hearing impaired people continue to be matched over time (not only during fitting process), as well as the quality and effectiveness of the assistance offered by Brazilian publicly-funded audiology services10,25–28.

In relation to hours of hearing aid use, most of users reported to use hearing aids for at least 8 hours daily and the average of use was 8.6 hours, which suggests hearing aids use during most of daily activities.

The average of use seen in this study is lower than the daily average of 9.5 hours found in United States7.

Practically all users of this study (99.5%) needed some kind of intervention after one year, and 40.5% had substantial problems with their hearing aids requiring major interventions. This rate was similar to the one found in U.K.6, in which 39% of hearing aid users needed major interventions after a reassessment appointment, yet they were subjects who had not made any kind of follow-up during three years of hearing aid use.

According to Table 3, the most recurrent interventions needed were different from U.K. study6 and consisted basically of orientation and counseling procedures, such as “explanation on phone use” (31.5%), “explanation on maintenance and cleaning” (28%) or “counseling about benefits and limitations of hearing aids” (22.5%). Also there was necessity of interventions for problems due to long term use, like “alteration of more than 5 dB in hearing aid gain” (26%) and “earmold retubing” (5.5%).

It is also important to highlight the amount of users that needed “explanation on draining and purchase of batteries” (11.5%), who did not know about the necessity of changing batteries or where to buy them, even after one year of hearing aid use. Some subjects were not using effectively their hearing aids because they did not have financial resources to buy batteries, so they did not wear any hearing aid for some period or used them for few hours to save battery charge.

Some users of this study still kept on wearing their hearing aids even with substantial problems for use, like faulty earmolds, faulty hearing aids or drained battery. Many of them were not aware of the necessity of adjustments and maintenance over time, for many “it was enough to use hearing aids just the way they were given”, according some users of this study. This behavior was also seen in other Brazilian hearing aid users9 and was different from the conception of users from other countries6,14.

Based on the facts seen in this study, many Brazilian users still have doubts and difficulties in dealing with their hearing aids, even with orientations received during fitting process. Considering that most of users are elderly people, with uncompleted elementary school and poor speech comprehension due to hearing loss, probably the time granted for orientation and counseling is not enough to elucidate all questions they have, which damages use, benefit, satisfaction and even adherence to hearing rehabilitation, as well as its effectiveness over time16,17,19,20.

According to SADL™ analysis, 97.49% of hearing aids users were satisfied and global satisfaction mean score was 6.0 (Table 4), corresponding to “very satisfied” with hearing aids3. It was the highest mean score compared to others from literature, higher than 5.27 of Australian hearing aid users13, 4.87 of American users29, 5.28 of elderly users from the state of Tocantins (Brazil)30, 5.55% from other Brazilian study31 and 5.77% of Brazilian users with profound or severe hearing loss32.

All scores from SADL™ subscales also represented high level of satisfaction with hearing aids3 within the users. “Service and costs” subscale had the highest score (6.3) and “Positive effects” the lowest (5.7%), even though all subscales also had scores within “very satisfied”3.

The application of question 14 from SADL™ differently from the original3 was an effective approach to verify satisfaction with financial costs associated to hearing aid use. Subjects with financial difficulties could reveal they were not using their hearing aids because they did not have resources to purchase batteries or pay the repair costs.

SADL™ questionnaire was chosen for containing direct questions, being focused on clinical application and it has been used to evaluate satisfaction in Brazilian hearing aid users from other publicly-funded audiology services30–34. However, despite the high level of satisfaction observed among the participants of this study, it is questionable how well this instrument can evaluate hearing aid satisfaction of users with this profile, because most of them needed explanations from the researcher to be able to answer the questions. Alterations in questions involved language simplification, use of practical examples, graphics and illustrations. Besides, many users showed an attitude of “gratitude” for all the assistance received and gave overestimated answers in questionnaire, which did not match the reality, behavior also seen in other Brazilian study10.