An electroacoustic analysis of over-the-counter hearing aids

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.

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.

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.

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.