A qualitative framework for understanding hearing-aid gain self-adjustment

Studies employing and evaluating hearing-aid self-adjustments frequently label the resulting settings as 'preferences' without questioning that label. There is a lack of inquiries into the rationale behind participants' choices or their approach to self-adjustment. We here employed a think-aloud protocol concurrent with individuals' self-adjustments to capture qualitative perspectives on these processes. Thirty-six adult hearing-aid users were asked to verbalise what they were thinking while adjusting to their preference three stimuli (music, speech or speech in noise) using three control interfaces (1 slider jointly controlling bass/treble, 2 sliders separately controlling bass and treble or 3 sliders controlling bass, mid and treble). Audio-video recordings were transcribed, annotated and analysed using inductive content coding and thematic analysis. Participants' approach and navigation of the self-adjustment process was best defined as a continuum between exploratory and anticipatory archetypes, with both types sometimes occurring at different stages within the same adjustment. The exploratory type initially assesses control functions, then selects the optimal setting from available options, and evaluates sound changes affectively in isolation or comparatively against prior settings. The anticipatory type begins by evaluating the sound, identifying issues, adjusting settings guided by past experiences, and evaluating adjustments against the identified issues. Additionally, the descriptors elicited during adjustments generally agreed with expert-based data. The resulting qualitative framework of self-adjustment helps explain both how hearing-aid users navigate the personalisation process and how self-adjustment can promote greater understanding of the options available and greater ownership in that process.