by Neil Bauman, Ph.D.
A man explained,
Austin TX is a large and sophisticated city, but I haven’t been able to find a single hearing aid dispenser who has the equipment for using real ear speech mapping. My readings tell me that speech mapping is the one essential thing I should do when buying new hearing aids but it seems unavailable here.
The last audiologist I talked to said that certain models of hearing aids now have circuits that do the same job as the traditional probe and collar for mapping. If so, I assume the audiologist would need to have the proprietary software (and coupler?) for that brand of hearing aid. In researching online I’ve come across implied references to a Siemens model and the Starkey S series and Starkey Zon, but no actual solid information.
My question: do you know whether there are BTE models that have the circuitry for doing the same job as the traditional real ear speech mapping?
Unfortunately, what you have found is true all over the country. Real ear testing is not being done like it should be. Since it is part of the code of “best practices” for audiologists, you’d think all audiologists would be using it in order to give their clients the best possible hearing aid fitting. If audiologists won’t follow their best practices, it should not be surprising that hearing aid dispensers, as opposed to audiologists, are even less likely than audiologists to do real-ear testing.
Real ear testing is important to knowing whether the fitting is truly matching your hearing loss or not.
Now, to answer your question about hearing aids doing the same job as real ear testing, since I’m no expert on this, I asked one prominent audiologist, who is a proponent of real ear testing, what his thoughts were on the subject.
There is some truth in what the writer says indirectly. The major manufacturers are getting much closer to prescribed targets with their first fits. They are also getting clever and seem to be using the speaker as a microphone to do an estimated RECD (Real Ear to Coupler Difference). While this isn’t actually ANSI standard real ear measurement, it does make a very good attempt to take ear canal acoustics into account. You will not find much, if any, documentation on these techniques as they fall into the realm of “trade secrets”.
Ideally, more hearing aid fitters should use independent probe microphone measurements [real ear testing] and speech mapping, but since that is not the case, the manufacturers are implementing ways to improve fittings and decrease the number of returns for credit.
Thus, it appears that real ear testing is still the best way to know your hearing aids match your hearing needs, but if you can’t find someone in your area that does real ear testing, then your next best alternative is to be fitted by someone that uses RECD.