Remote or in-clinic? The effect of service delivery mode on hearing aid output: study protocol for a double-blinded, randomised trial in adults with mild to moderate sensorineural hearing loss

Abstract

Abstract Background Teleaudiology can potentially improve access to hearing healthcare services. Remote hearing aid fittings offer a new mode of service delivery that removes barriers of geography and access to an audiologist. Real-ear measurements (REMs) are the gold standard for hearing aid output verification but require in-clinic appointments. This study will investigate whether remote hearing aid fittings can provide clinically equivalent outcomes when compared to current, in-clinic, best practice guidelines. Research design A repeated measure, double-blinded crossover design will be used. Participants will be randomly allocated to one of two groups to determine order of intervention, balanced for degree of hearing loss. Study sample Sixty adults with mild to moderate hearing loss and at least 1 year of experience with hearing aids will be recruited. Data collection and analysis Participants will complete two hearing aid fitting protocols, one using an in-clinic fitting process and the other using a remote (at-home) fitting process. In-clinic fittings will include REMs with adjustments to standard (NAL-NL2) prescription targets. The two fitting protocols will then be randomly assigned to participants in a crossover design, so participants and researchers will be blinded to the order of the two fitting protocols. Participants will then have a 4-week period with follow-up appointments for participant-directed gain adjustment. For each fitting protocol, participants will complete objective measurements of final hearing aid output with REMs, speech-in-noise testing, subjective measurements of hearing aid performance, and quality of life measurements. They will then begin an identical period of living with, adjusting, and objective assessment with the other fitting protocol. Data will be analysed as repeated measures with statistical control for potential confounding variables. Results Data will compare the four-frequency average real-ear aided response (4FREAR) for hearing aids programmed in-clinic and hearing aids programmed remotely, after participant-directed gain adjustments. Secondary measures will assess clinically significant differences in estimated speech intelligibility, hearing-related quality of life, hearing aid benefit, sound quality and preference, and speech-in-noise ability. Conclusions This study will inform the development of best practice guidelines for remote hearing aid fittings. If no clinically significant differences are found between in-clinic and remote fit hearing aids, it has the potential to expand teleaudiology initiatives. Trial registration Australian New Zealand Clinical Trial Registry, ACTRN12623000028606p. Date of registration: 12 January 2023.