Abstract
A then-test technique was used to investigate the possibility of a response shift in the Glasgow hearing aid benefit profile (GHABP). Following completion of part 1 of the GHABP, 16 adults were invited for hearing-aid follow up appointments. In accordance with then-test technique, participants were asked to think back to before they had their hearing-aids fitted and the GHABP part 1 was completed again to re-establish the disability and handicap scores. These scores were then compared with the initial GHABP part I scores. Paired T testing and Wilcoxon Rank tests were carried out to investigate the statistical significance of the response shift effect. Statistically significant differences were seen between initial and retrospective GHABP (disability) scores using t test. No significant differences could be seen between the initial and retrospective handicap scores. Results suggest participants may have demonstrated a possible response shift phenomenon with the disability construct of the GHABP questionnaire, related to a possible re-calibration effect or a denial of disability effect. This exploratory study suggests that the GHABP questionnaire may be subject to a response shift phenomena. We suggest that further more robust studies are completed to verify this and recommend that this could have psychological impact on participants when explaining the results of the outcome measure and may affect hearing aid use. There is also potential for this phenomenon to affect global GHABP scores specifically when demonstrating to stakeholders the overall success of an audiology service.