Trial: OTC and audiologist-fitted hearing aids perform with equal clinical effectiveness...but is the trial reliable?



A low price alone was never going to guarantee over-the-counter (OTC) self-fitting hearing aids credibility as the new kids on the block; it is scientific studies that light up the movers and shakers.

Cue cocky yells of delight from the new kids, then, after a new trial published in a JAMA journal measured up the changes in the hearing of a group of 64 patients with hearing loss, half evaluated after wearing a self-fitted OTC device, the other half after wearing an audiologist-fitted aid. In both groups, which were randomised, the device used was a Lexie Lumen hearing aids, powered by Bose, and made by the South Africa-based company HearX, which now has devices on sale in the USA in the Costco chain stores.

The results of this randomised clinical effectiveness research, conducted in South Africa between April 14 and August 29, 2022 fed the conclusion that "self-fitting OTC hearing aids with remote support yielded outcomes at 6 weeks post fitting comparable to those of hearing aids fitted using audiologist best practices".

With no meaningful differences evident between the groups on any outcome measures, the trial "suggest that a self-fitting OTC hearing aid may be an effective intervention option for individuals with mild to moderate hearing loss and produce self-perceived and clinical outcomes similar to those of an audiologist-fitted hearing aid," claim the authors.

Only one device studied

But the study was funded by none other than the company that makes the very same Lexie Lumen hearing aid under scrutiny: HearX.

And the study's authors themselves, Karina C. De Sousa, Vinaya Manchaiah, David R. Moore et al point out some limitations that bring much pause for thought: The study was not blinded; and it investigated only one self-fitting OTC device with one fitting method.

"Other devices and fitting methods may produce outcomes with variable success," the authors point out.

"The sample size did not allow for subgroup analysis, such as age, which could influence self-fitting outcomes if there are varying levels of digital proficiency; this limits the ability of the study to identify and resolve potential problems in the self-fitting model," they continue, while "possible recall bias for the wear time of the hearing aids may be present since the actual duration of use was not captured using data logging. Finally, the results only report outcomes up to 6 weeks post fitting. Further field research investigating long-term outcomes is needed."

Another factor that should, at this stage, dampen any cries of an early victory for OTC advocates comes in the study's section on disclosing conflicts of interest. HearX paid several members of the study team in consultation fees, grant support, and personal fees. Although declared, with some of these fees paid outside the submitted work, it cannot easily be argued that the disclosures do not undermine the study.

Since the August 2022 greenlighting of OTC hearing aid sale in the USA, countries not directly affected by those rules, but unable to stop inhabitants buying such items online, are carefully debating how markets and the profession will be affected. While a small study with big limitations will inevitably be used to market the OTC device, the world awaits bigger and more convincing studies on their effectiveness versus traditional audiologist-fitted aids. When that happens, the new kids will be dancing down the aisles of the big-box stores and making faces as they go past traditional hearing centres.

Meanwhile, market activity begins to sort the question out itself, as new players arrive and manufacturers who have for so long held sway over their territory also dive in with their own OTC products. Is an eagerness not to be left behind the best indication we have for now that the effectiveness of the self-fitted device might not be too far behind that of the hearing aid fitted by the audiologist?

Source: JAMA Otolaryngology - Head and Neck Surgery