Manchaiah, V., De Sousa, K., Oosthuizen, I., Graham, M., Moore, D., & Swanepoel, D.W.
American Auditory Society (AAS), Scottsdale, Arizona (USA), March 2023.
Publication year: 2023

Objectives: Over-the-counter (OTC) hearing aids present more accessible and affordable solutions compared to traditional prescription hearing aids. Most existing research on OTC hearing aids was performed on early-generation direct-to-consumer devices such as personal sound amplification systems. The aim of this study was to compare the outcomes of self-fitting OTC hearing aids when compared to audiologist-fit hearing aids. Our hypotheses was that the self-fitting hearing aids will be non-inferior to audiologist-fit hearing aids in terms of self-reported as well as behavioral outcomes.

Design: The first of two studies included a prospective cross-sectional survey design (n=656) and compared hearing aid benefit and satisfaction measured using the International Outcome Inventory for Hearing Aids (IOI-HA) between individuals who obtained prescription hearing aids from hearing care professionals (HCPs) or self-fitting OTC HAs. The second study included a randomized parallel-group clinical effectiveness trial (n=68) comparing the outcomes of self-fitting OTC hearing aids to the hearing aids fit by HCPs. Outcome measures included the Abbreviated Profile of Hearing Aid Benefit (APHAB), IOI-HA, QuickSIN and digits-in-noise (DIN) tests.

Results: The first cross-sectional suggested that there was no significant difference in overall hearing aid outcomes between prescription hearing aid users fit by HCPs and users of self-fitting OTC hearing aids using regression analyses controlling for age, gender, duration of hearing loss, duration before hearing aid purchase, self-reported hearing difficulty, and unilateral versus bilateral fitting. In the second trial, the groups did not differ significantly in age or four-frequency pure tone average. After the two-week field trial, the self-fitting group had an initial advantage when compared to HCPs group on the self-reported benefit and satisfaction measures, including the APHAB (Cohen’s d for independent samples t-test, -0.4; 95% CI -0.9 to 0.1) and IOI-HA (effect size r for Mann-Whitney test, 0.3; 95% CI 0.0 to 0.5), but not in speech recognition in noise. However, at the end of the six-week trial, no meaningful differences were evident between the groups on any of the outcome measures.

Conclusions: The results of the two studies presented suggest that self-fitting OTC hearing aids with remote support provide comparable outcomes to hearing aids fit by HCPs using best practice. These studies provide early evidence to inform clinical practice and policy in relation to OTC hearing aids.