An electroacoustic analysis of over-the-counter hearing aids

Abstract

Purpose: To determine whether 11 over-the-counter (OTC) hearing devices have the flexibility to provide adequate gain and output for 3 common hearing loss configurations.

Method: The 11 OTC hearing devices were separated into 2 price groups: a low-range group (<$100) consisting of 8 hearing devices and a midrange group ($100-$500) consisting of 3 hearing devices. Gain and output were prescribed for 3 hearing loss configurations using National Acoustic Laboratories prescriptive procedures. Low-range hearing devices were measured electroacoustically, and technical specifications were used as the source of electroacoustic information for the midrange hearing devices.

Results: Overall, midrange hearing devices met gain and output targets to a greater extent than did low-range devices. All low-range devices could be classified as special-purpose hearing aids with low-frequency emphasis. The low-range group had high equivalent input noise levels and potentially posed a residual hearing safety hazard.

Conclusions: The low-range OTC devices were found to be electroacoustically inadequate to meet the needs of the hearing impaired. Midrange OTC hearing devices are arguably a good solution for the cost-conscious consumer who cannot afford professional audiologic rehabilitation, especially if considered an interim step in the rehabilitation process.