Abstract
PURPOSE: In this study, we compare the efficacy and effectiveness of gain-frequency responses of evidence-based presets developed by our lab for over-the-counter hearing aids to conventional National Acoustic Laboratories' nonlinear fitting procedure, version 2 (NAL-NL2) gain-frequency response and to gain-frequency response of a personal sound amplification product (PSAP). We hypothesized that the hearing aids with our presets would perform better than a PSAP with poor frequency response and comparably to the hearing aid with NAL-NL2 frequency response. METHOD: We used a single-blinded, randomized cross-over design to compare audibility, speech recognition, sound quality, listening effort, and subjective preferences in 37 participants in laboratory settings and following field trials. RESULTS: The presets developed in our lab showed comparable outcomes to the hearing aids with NAL-NL2 gain-frequency response in most measured domains. Performance with the presets was better than the PSAP gain-frequency response in the domains of listening effort and sound quality in laboratory testing and speech recognition in our real-world measures. We also found that most participants (54.05%) preferred our presets over the PSAPs and were willing to pay significantly more to purchase the hearing aids with our presets. CONCLUSION: Our evidence-based presets have better outcomes than a PSAP with a single, poorly suited frequency response while performing comparably to the clinical best-practice National Acoustic Laboratories condition.