Effectiveness of an over-the-counter self-fitting hearing aid compared to an audiologist-fitted hearing aid: A randomized clinical trial

Importance: Hearing loss is a highly prevalent condition, with numerous debilitating consequences when left untreated. However, less than 20% of adults with hearing loss in the United States use hearing aids. Over-the-counter (OTC) hearing aids became available in October 2022 to improve access and affordability. However, clinical effectiveness studies of available OTC hearing aids using the existing devices in the market are limited. Objective: To compare the clinical effectiveness of a self-fitting OTC hearing aid with remote support to a hearing aid fitted using audiologist best practices. Design, setting, and participants: A randomized parallel-assigned clinical effectiveness trial was conducted between April to August 2022. Sixty-eight adults with self-perceived mild-to-moderate hearing loss were recruited and randomly assigned to either the self-fitting (SF) group or an audiologist-fitted (AF) group. Following hearing aid fitting, participants first completed a two-week, take-home field trial without any support. Access to fine-tuning for both groups was only available after the two-week trial. The level of support and adjustment was done remotely for the SF group per request and by the audiologist for the AF group. Participants were then re-assessed after an additional four-week take-home trial. Interventions: A commercially available self-fitting OTC hearing aid was provided to participants in the SF group who were expected to set up the hearing aids using the commercially supplied instructional material and accompanying smartphone app. In the AF group, audiologists fitted the same hearing aid according to a commonly used (NAL-NL2) prescriptive gain target using real-ear verification with hearing aid use instruction. Main Outcomes and Measures: The primary outcome measure was self-reported hearing aid benefit, measured using the Abbreviated Profile of Hearing Aid Benefit (APHAB). Secondary measures included the International Outcome Inventory for Hearing Aids (IOI-HA) and speech recognition in noise measured using the QuickSIN and digits-in-noise (DIN) tests. All measures were completed at baseline and at two intervals following hearing aid fitting (two- and six weeks). Results: Sixty-four participants were included in the analytic sample, with equal number of participants (n = 32) randomized into SF and AF groups. The groups did not differ significantly in age (effect size r, -0.2; 95 CI -0.3 to 0.2) or four-frequency pure tone average (PTA; effect size r, 0.2; 95% CI -0.1 to 0.4). After the two-week field trial, the SF group had an initial advantage compared to the AF group on the self-reported benefit measures (APHAB; Cohen's d, -0.5; 95% CI -1.0 to 0, IOI-HA; effect size r, 0.3; 95% CI 0.0 to 0.5) but not speech recognition in noise. At the end of the six-week trial, no meaningful differences were evident between the groups on any outcome measures. Conclusion and relevance: This effectiveness trial indicates self-fitting OTC hearing aids with remote support provides comparable outcomes to a hearing aid fitted using audiologist best practices at 6-weeks post-fitting. Self-fitting OTC hearing aids can provide an effective intervention for mild to moderate hearing loss.