{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T19:43:38Z","timestamp":1787773418872,"version":"build-2784847793"},"reference-count":21,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2025,2,13]],"date-time":"2025-02-13T00:00:00Z","timestamp":1739404800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Institute of Health","award":["#NIHR01DC021653"],"award-info":[{"award-number":["#NIHR01DC021653"]}]},{"name":"National Institute of Health","award":["T32DC012280"],"award-info":[{"award-number":["T32DC012280"]}]},{"name":"National Institutes of Health under Ruth L. Kirschstein National Research Service Award","award":["#NIHR01DC021653"],"award-info":[{"award-number":["#NIHR01DC021653"]}]},{"name":"National Institutes of Health under Ruth L. Kirschstein National Research Service Award","award":["T32DC012280"],"award-info":[{"award-number":["T32DC012280"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Audiology Research"],"abstract":"<jats:p>Objectives: To investigate the gain provided by self-fitting over-the-counter (SF-OTC) hearing aids compared to clinical NAL-NL2 targets, the differences between various FDA-approved SF-OTC devices, and potential changes in gain over time. Methods: Two experiments were conducted: (1) a cross-sectional comparison of six SF-OTC hearing aids (n = 43) and (2) a longitudinal evaluation of gain within five days of self-fitting and four additional time points (n = 15). Real-ear measurements (REMs) were used to measure gain. Results: SF-OTC hearing aid gain corresponded with 10 dB SPL but not 5 dB SPL criteria from NAL-NL2 targets. Differences between NAL-NL2 targets and gain did not differ significantly between devices. There were no significant changes in gain over time for any input level. Conclusions: SF-OTC hearing aids generally provide user-selected gain levels lower than clinical targets, particularly at higher frequencies. The gain remains stable over time, indicating limited user adjustment after initial fitting. OTC hearing aid manufacturers should consider implementing fitting algorithms that allow for gradual user acclimatization.<\/jats:p>","DOI":"10.3390\/audiolres15010017","type":"journal-article","created":{"date-parts":[[2025,2,13]],"date-time":"2025-02-13T12:06:32Z","timestamp":1739448392000},"page":"17","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Gain Analysis of Self-Fitting Over-the-Counter Hearing Aids: A Comparative and Longitudinal Analysis"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7187-9281","authenticated-orcid":false,"given":"Megan","family":"Knoetze","sequence":"first","affiliation":[{"name":"Department of Speech-Language Pathology and Audiology, University of Pretoria, Lynnwood Road & Roper Street, Pretoria 0028, South Africa"},{"name":"Virtual Hearing Lab, a Collaborative Initiative Between the University of Colorado School of Medicine, Aurora, CO 80045, USA, and the University of Pretoria, Pretoria, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1254-8407","authenticated-orcid":false,"given":"Vinaya","family":"Manchaiah","sequence":"additional","affiliation":[{"name":"Department of Speech-Language Pathology and Audiology, University of Pretoria, Lynnwood Road & Roper Street, Pretoria 0028, South Africa"},{"name":"Virtual Hearing Lab, a Collaborative Initiative Between the University of Colorado School of Medicine, Aurora, CO 80045, USA, and the University of Pretoria, Pretoria, South Africa"},{"name":"Department of Otolaryngology-Head and Neck Surgery, University of Colorado School of Medicine, Aurora, CO 80045, USA"},{"name":"UCHealth Hearing and Balance, University of Colorado Hospital, Aurora, CO 80045, USA"},{"name":"Department of Speech and Hearing, School of Allied Health Sciences, Manipal Academy of Higher Education, Manipal 576104, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kayla","family":"Cormier","sequence":"additional","affiliation":[{"name":"Department of Speech, Language, and Hearing Sciences, University of Colorado Boulder, Boulder, CO 80309, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-5360-5587","authenticated-orcid":false,"given":"Carly","family":"Schimmel","sequence":"additional","affiliation":[{"name":"Department of Speech, Language, and Hearing Sciences, University of Colorado Boulder, Boulder, CO 80309, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8568-1420","authenticated-orcid":false,"given":"Anu","family":"Sharma","sequence":"additional","affiliation":[{"name":"Department of Speech, Language, and Hearing Sciences, University of Colorado Boulder, Boulder, CO 80309, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8313-1636","authenticated-orcid":false,"given":"De Wet","family":"Swanepoel","sequence":"additional","affiliation":[{"name":"Department of Speech-Language Pathology and Audiology, University of Pretoria, Lynnwood Road & Roper Street, Pretoria 0028, South Africa"},{"name":"Virtual Hearing Lab, a Collaborative Initiative Between the University of Colorado School of Medicine, Aurora, CO 80045, USA, and the University of Pretoria, Pretoria, South Africa"},{"name":"Department of Otolaryngology-Head and Neck Surgery, University of Colorado School of Medicine, Aurora, CO 80045, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,13]]},"reference":[{"key":"ref_1","unstructured":"Food and Drug Administration (2022). 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