Patient-Reported Outcome Measures for Hearing Aid Benefit and Satisfaction: Content Validity and Readability

Numerous patient-reported outcome measures (PROMs) are available to measure hearing aid benefit and satisfaction. It is unclear to what extent currently available PROMs on hearing aid outcomes, often developed decades ago, meet current guidelines for good content validity and readability. This study evaluated the content validity and readability of PROMs that focus on perceived hearing aid benefit and/or satisfaction.

A literature review was conducted to identify eligible instruments. Content validity evaluation included mapping extracted questionnaire items to the World Health Organization's International Classification of Functioning, Disability and Health (ICF) framework. In addition, study design in content validity methodology was evaluated using the COnsensus-based Standards for the selection of health Measurement INstruments study design checklist for PROM instruments. Readability was estimated using the Simple Measure of Gobbledygook measure.

Thirteen questionnaires were identified and evaluated. Item content focused primarily on the components of environmental factors as well as activity limitations and participation restrictions with less emphasis on body functions and personal factors. The content validity methodology analysis revealed an underuse or lack of reporting of a qualitative methodology in assessing patient and professional perspectives. All the included questionnaires exceeded the recommended sixth-grade reading level.

The categories covered by hearing aid PROMs vary considerably, with no single instrument comprehensively covering all the key ICF components. Future development of hearing aid outcome measures should consider a mixed methodology approach for improved content validity and ensure an appropriate reading level.