Hearing aid outcomes: effects of gender and experience on patients' use and satisfaction

To use the International Outcome Inventory for Hearing Aids (IOI-HA) with patients having advanced hearing aid technology to assess their satisfaction and benefit focusing on gender and experience effects, compare to norms, and use the IOI-HA and a practice-specific questionnaire to monitor the quality of the services provided by a dispensing practice.

A study of 160 potential participants who had worn their newly purchased multichannel digital hearing aids having directional microphones for at least three months, completed a trial period, and should have had time to acclimatize to them. English-speaking, private or insurance paying, competent, adult patients from a private practice were mailed a 12-item practice-specific questionnaire and the seven-item IOI-HA.

Of the 160 questionnaires mailed, 73 were returned for a 46% return rate. Of those, 64 were useable. Participants included male (34) and female (30), new (30) and previous (34) hearing aid users, who self-selected their participation by returning the questionnaires. The practice-specific questionnaire assessed patients' demographics and the quality of services received. The IOI-HA was analyzed according to an overall score and on two different factor scores. A power analysis revealed that 19 respondents per group were needed for the IOI-HA results to have a statistical power of .80 and probability of a Type II error of .20 for detecting a significant difference at the p < 0.05 level. Similar to earlier studies, no significant differences were observed either for any of the main effects or interactions for gender or user experience for the two IOI-HA factors and overall scores. A significant, but weak, positive correlation (r = .34; df = 63; p < .05) was observed between patients' overall satisfaction as indicated from the IOI-HA and the practice-specific quality assurance satisfaction question. T-tests on IOI-HA items 4 (satisfaction) and 7 (quality of life) revealed that the present participants' responses were significantly higher than for those in the normative study.

Gender and hearing aid experience did not influence these patients' responses on the IOI-HA, and all respondents were satisfied with their hearing aids and the practice that dispensed them. No major differences were found between these patients' IOI-HA results and normative data suggesting that both sets of respondents were satisfied with their hearing aids. However, limited statistical comparisons for the satisfaction and quality of life items revealed significant differences in favor of these participants' scores over those in the normative study. This suggested that the advanced hearing aid technology used here had a positive effect on patients' ratings and that the IOI-HA norms should be updated periodically to reflect changes in technology.