Evaluation of the Self-Fitting Process with a Commercially Available Hearing Aid.

BACKGROUND: Hearing aids and personal sound amplification products that are designed to be self-fitted by the user at home are becoming increasingly available in the online marketplace. While these devices are often marketed as a low-cost alternative to traditional hearing health-care, little is known about people's ability to successfully use and manage them. Previous research into the individual components of a simulated self-fitting procedure has been undertaken, but no study has evaluated performance of the procedure as a whole using a commercial product.

PURPOSE: To evaluate the ability of a group of adults with a hearing loss to set up a pair of commercially available self-fitting hearing aids for their own use and to investigate factors associated with a successful outcome.

RESEARCH DESIGN: An interventional study that used regression analysis to identify potential contributors to the outcome.

STUDY SAMPLE: Forty adults with mild to moderately severe hearing loss participated in the study: 20 current hearing aid users (the "experienced" group) and 20 with no previous amplification experience (the "new" group). Twenty-four participants attended with partners, who were present to offer assistance with the study task as needed.

DATA COLLECTION AND ANALYSIS: Participants followed a set of written, illustrated instructions to perform a multistep self-fitting procedure with a commercially available self-fitting hearing aid, with optional assistance from a lay partner. Standardized measures of cognitive function, health literacy, locus of control, hearing aid self-efficacy, and manual dexterity were collected. Statistical analysis was performed to examine the proportion of participants in each group who successfully performed the self-fitting procedure, factors that predicted successful completion of the task, and the contributions of partners to the outcome.

RESULTS: Fifty-five percent of participants were able to successfully perform the self-fitting procedure. Although the same success rate was observed for both experienced and new participants, the majority of the errors relating to the hearing test and the fine-tuning tasks were made by the experienced participants, while all of the errors associated with physically customizing the hearing aids and most of the insertion errors were made by the new participants. Although the majority of partners assisted in the self-fitting task, their contributions did not significantly influence the outcome. Further, no characteristic or combination of characteristics reliably predicted which participants would be successful at the self-fitting task.

CONCLUSIONS: Although the majority of participants were able to complete the self-fitting task without error, the provision of knowledgeable support by trained personnel, rather than a fellow layperson, would most certainly increase the proportion of users who are able to achieve success. Refinements to the instructions and the physical design of the hearing aid may also serve to improve the success rate. Further evaluation of the range of self-fitting hearing aids that are now on the market should be undertaken.