Has anyone ever looked at testing the performance of personal sound amplification products (PSAPs) that you purchase online or at retail stores, versus hearing aids?
There have been a few comparative studies, but one that immediately comes to mind is from Robyn Cox’s lab, and she talked about it in an AudiologyOnline article last year (Cox, 2014). Since the time of Robyn’s article, I see that the research was presented at the American Auditory Society (Xu, Johnson, Cox & Breitbart, 2015) and the full paper can be viewed at the HARL website (see link in reference list below). These authors reported findings comparing PSAPs to entry-level hearing aids and to premium hearing aids. Testing was conducted with two different PSAPs and two different types of hearing aids from two different manufacturers, for a total of six devices. Each of the devices was programmed to NAL-NL2 targets. The products were tested using three different sounds: speech, everyday noises (e.g., hair dryer, dishes, electric fan, keyboard typing, silverware, and pen tapping) and music. These signals were recorded through each hearing aid device while fitted on the KEMAR, and then played back to the hearing-impaired subjects.
There were 20 adult listeners who had mild to moderate hearing loss, and they listened to these speech, music, and noise samples. The comparisons were conducted using a double round-robin, paired comparison; similar to a sports tournament where everybody plays against everybody else. A PSAP might compete against a premier hearing aid and the subject had to pick which one is best. Then the PSAP may compete against the entry-level hearing aid, and so on.
Overall, they found no significant differences among any of the three products for music and noise. For speech, both hearing aids were better than the PSAP, but there was no difference between the entry-level and the premium-level hearing aids for listening to speech.
The differences among PSAPs, entry-level, and premium hearing aids may not be as large as some people believe. There are two caveats to this. One is that that they were all fitted to NAL-NL2 targets. You could not compare this to someone who walked into a store, bought a PSAP off the shelf and put it into his or her ear. The second is that these were measures in the laboratory. To define modern hearing aids, and particularly premium hearing aids, you might argue that there are a many features that would not show up in that particular test. Obviously, some of the entry-level hearing aids or PSAPs are not going to have the same signal detection, automatic and adaptive processing as the premier models. But, does everyone need this? If you’re interested in how entry level products stack up against premier levels products in the real world, that’s a different question, but you’ll get a good idea of the answer in Cox, Johnson, & Xu (2014).
This Ask the Expert was taken from the Siemens Expert Series text course, Day-to-Day Hearing Aid Fittings: Clinical Nuggets from Recent Research.
Cox, R. (2014, April). 20Q: Hearing aid provision and the challenge of change. AudiologyOnline, Article 12596. Retrieved from: http://www.audiologyonline.com
Cox, R.M., Johnson, J.A., & Xu, J. (2014). Impact of advanced hearing aid technology on speech understanding for older listeners with mild to moderate, adult-onset, sensorineural hearing loss. Gerontology, 60(6), 557-68. doi: 10.1159/000362547