Self-reported outcome in new hearing aid users over a 24-week post-fitting period

Evidence for the existence of auditory acclimatization is mixed, and the implications for clinical practice are unclear. The aim of this study was to seek evidence of perceived changes in performance over a 24-week post-fitting period. Thirty-two new, elderly subjects were recruited and fitted monaurally with the same model of linear, programmable hearing aid that provided in excess of 20-dB insertion gain at 2000-4000 Hz. The Glasgow Hearing Aid Benefit Profile (GHABP) was used to measure self-reported changes over time. The questions concerning benefit and satisfaction were modified to produce two versions: half of the subjects reported changes relative to the time of fitting, while the remainder reported changes relative to the previous occasion on which they completed the GHABP (3 weeks earlier). Subjects reported using hearing aids in excess of 90% of the time when in listening situations that cause difficulty. The median residual disability measure from the GHABP remained low (10-20%) over the duration of the study. The median scores for additional benefit and satisfaction showed a small but statistically significant improvement over the first 3 months of hearing aid use but only for the subjects who referenced this to their perceived performance 3 weeks earlier. The limited evidence for self-reported improvements in benefit and satisfaction over time reported to date must be tempered by the possibility of response bias arising from the method used to measure changes over time.