Hearing Aid OTC Sales and Self-Fitting

On July 12^th, 2017 the U.S. House of Representatives passed the FDA Reauthorization Act of 2017, which includes the Over-the-Counter Hearing Aid Act, and allows for hearing aid OTC sales.¹   

The Act creates a new class of over-the-counter hearing aids and allows non-prescription hearing devices to be marketed to treat mild-to-moderate hearing loss.  This bill is incorporated into the larger FDA Medical Device User Fee Amendments (MDUFA) Act of 2017.  This is in line with Senate Bill (SB-9), yet to be passed, but is expected to be, and signed into law by the President.² 

Over-the-counter hearing devices are intended to be affordable, readily available, and much more in line with what American consumers are willing to spend to improve their hearing.

Self-fitting of Hearing Aids Implies Self-diagnosis

Is self-diagnosis of hearing loss a problem?  Not really, because the vast majority of individuals self-diagnose the fact that they have a hearing loss.  It is for this reason that they seek amplification assistance.  Surveys have shown that the major reason adult consumers look toward amplification is because they notice that their hearing has become poorer.³   It is not because someone tested their hearing and then told them that they had a loss.  An audiogram confirms what they already know.  It primarily puts numbers to their hearing levels, numbers in dB (decibels) that are meaningless to most.  The use of an audiogram to fit hearing aids successfully has come under serious scrutiny.  It has been shown that meeting a prescriptive target does not guarantee hearing aid success, nor that it is even a good starting point.^4,5,6,7,8

Are Consumers Able to Self-Fit Their Hearing Loss?

Does knowing that one has a hearing loss also mean that they can then self-fit their loss?  Laboratory studies of self-fitting hearing aids show that even rudimentary self-fitting systems are successful.^9,10,11,12   For example, a smart phone app fitting, starting without an audiogram, showed that 72% of research participants found such a fitting system equivalent or better than settings provided with a prescriptive fitting method based on pure-tone audiometric thresholds.¹³   During the late 1960s, 1970s, and early 1980s, essentially every hearing aid manufacturer offered a Master Hearing Aid that allowed the consumer to select their own amplification level (gain), along with selecting a response from pre-set options – all performed without an audiogram.  Literally hundreds of thousands of hearing aids were fitted successfully using such systems.  In essence, these were self-fit hearing aids because it was consumers who were making the determination as to what functioned best for them.  This procedure was subsequently replaced with hearing aid fitting formulae based on pure-tone thresholds, but as was pointed out above, and previously, such prescriptive formulae have not been shown to be reliable.¹⁴   

Where Does the Consumer Start?

Figure 1. The average judged value for all the hearing aid devices, regardless of the purchase price, was about 60, regardless of the advanced features. (Calculated by Killion from Van Vliet, 2002 data and replotted here).

There is no question that the first adjustment decision a hearing aid user makes relates to the overall loudness – a decision they can make better than can a third party.  The most common type of hearing loss results in a person having trouble hearing soft sounds.  It is for this reason that the hearing aid (an amplifier) is used.  What is concerning is that although hearing aid technology has advanced greatly in the past years, a review of studies shows that the user satisfaction has remained essentially the same (Figure 1).  The primary technology features for hearing aids (digital signal processing, directional microphones, feedback suppression systems, noise reduction, and compression) can be, and have been available in many of the products that will qualify as low-priced/affordable OTC hearing aids.

Effective Self-Fitting of Hearing Amplification Is a Reality

Is a consumer able to self-fit their hearing loss effectively?  In addition to the rudimentary self-fitting approaches referenced earlier in this post, and knowing the history of hearing aid fittings using Master Hearing Aids, self-fitting appears to be somewhat of a “normal” process.  The consumer makes the decisions as to what sounds appropriate to them.  Additionally, current technology at the user’s disposal tends to support this.

“Other market experiments showing the ability to effectively self-fit are proceeding in the form of smartphone apps that use the microphone and signal-processing power of the phone itself. Smartphone apps can function as self-fitted hearing aids when combined with consumer-grade earphones. One recent investigation showed that, when compared with conventional hearing aids that had been fit to research participants according to state-of-the-art professional fitting, the two smartphone apps yielded equivalent speech understanding in noise, higher user-perceived benefit, and better satisfaction in terms of adjustability (Amlani et al., 2013). This is convincing evidence that users can easily learn to manipulate an effective user interface to achieve benefit as good as that achievable with a conventionally-fit hearing aid. Self-fitting may even yield superior outcomes if the user can continually revise the fitting as he/she grows accustomed to amplification, and in different settings.”¹⁶

Up until the current legislation that will allow OTC sales of hearing aids, they were not allowed to be purchased over-the-counter.  Instead, people had to have a professional evaluate their hearing loss, set the hearing aid’s sensitivity and teach proper use.

However, in a landmark study, Indiana University researchers indicate hearing aids fitted by a patient are just as effective as those fitted by a professional audiologist using best practice procedures.¹⁷   The OTC model studied, when compared with a placebo and audiologist best practice model, yielded only slightly poorer outcomes than the audiology best practice model, but suggested that efficacious OTC models may increase accessibility and affordability of hearing aids for millions of older adults.   Study author and IU professor Larry Humes says:

“…that could have important implications for making hearing aids more accessible to the millions of people who need them but don’t have the money to buy them. He adds the current “best practices” model keeps millions of people from receiving the hearing tools they need.”

The study, supported by NIDCD (National Institute on Deafness and Other Communicative Disorders – NIH) summarized the findings stating that an OTC hearing aid delivery model for older adults with mild-to-moderate hearing loss reported a similar level of benefit as participants who purchased the same hearing aids through an audiologist following best practices.¹⁸

More studies are needed to assess the generalization of the results to other patient populations, other devices, and other models of OTC service delivery, according to Humes.  Still, the results are impressive and confirm that consumers can make self-fitting decisions that function well for them.

Additional studies at the NAL (National Acoustic Laboratories in Australia have also shown that consumers are able to self-fit hearing aids.  Convery et. al. sought to determine if hearing-impaired adults in the developing world could independently and accurately assemble a pair of hearing aids by following instructions that were written and illustrated according to best-practice health literacy principles.  They found that individuals of diverse backgrounds can manage the self-fitting hearing-aid assembly task as long as health literacy levels and cultural differences are considered,^19,20   The authors commented further that a self-fitting hearing aid, designed to be assembled and programmed without audiological or computer support, could bring amplification to millions of people in developing countries, who remain unaided due to the lack of a local, professional, audiological infrastructure.  The two blue-shaded comments to the right summarize their preliminary recommendations on self-fitting hearing aids in which they showed at last one (tested just one) currently available self-fitting product was comparable to those measured with professionally dispensed hearing aids.²¹

With the establishment of an OTC category, it is logical to expect considerable innovation in self-fitting and adjustment methods without the need for an audiogram.

Consumer Product or Medical Device?

Successful and massive use of smart phone apps; PSAPs, OTC, Internet and mail-order sales; general consumer amplification devices (iPods™, MP3 devices, amplified earphones, etc.); amplified telephones; TV and radio volume controls; etc. confirm that amplification for a person having difficulty hearing is not identified with a medical problem, but instead is much more closely identified to consumer products.  All definitions to the contrary do not change this reality. 

In the face of OTC hearing aid sales, the FDA Guidance for PSAPs should be eliminated.  It no longer makes any sense and contributes only to confusion.

References

1. S. House of Representatives. H.R. 2430 – FDA Reauthorization Act of 2017.  July 13, 2017
2. S. Senate. S9 – Over-the-Counter Hearing Aid Act of 2017.  https://www.warren.senate.gov/files/documents/3_21_17_Hearing_Aids_Bill_Text.pdf.
3. Kochkin S. (2002).  MarkeTrak VI: Hearing Aid Industry Market Tracking Survey 1984-2000.  Knowles Electronics, Inc.  
4. Hawkins D. and Cook J. (2003). Hearing aid software predictive gain values: how accurate are they?  The Hearing Journal. July, Vol. 56, No 7, pp 26, 28, 32, 34.
5. Aarts, N., Cafee, C. (2005). Manufacturer predicted and measured REAR values in adult hearing aid fitting: accuracy and clinical usefulness. J. Audiol. 44, 293-301.
6. Azah H. and Moore BCJ. (2007). The value of routine real ear measurement of the gain of digital hearing aids.  Journal of the American Academy of Audiology, 18(8), 653-664.
7. Sanders, J., Stoody, T., Weber, J., Mueller, H.G., 2015. Manufacturers’ NALNL2 fittings fail real-ear verification. Rev. 21 (3), 24.
8. Azah H, Moore BC, & Prasher D. (2012). The accuracy of matching target insertion gains with open-fit hearing aids. American Journal of Audiology, 21:175-180.
9. Elberling, C, & K Vejby Hansen (1999): Hearing instruments: Interaction with user preference. In Auditory Models and Non-Linear Hearing Instruments, Proc 18th Danavox Symposium (eds. AN Rasmussen, PA Osterhammel, T Andersen, & T Poulsen), 341-347.
10. Moore, BC, J Marriage, J Alcantara, & BR Glasberg (2005): Comparison of two adaptive procedures for fitting a multi-channel compression hearing aid. Int J Audiol, 44(6): 345-357.
11. Dreschler, WA, G Keidser, E Convery, & H Dillon (2008): Client-based adjustments of hearing aid gain: The effect of different control configurations. Ear & Hearing, 29(2): 214-227.
12. Zakis, JA, H Dillon, & HJ McDermott (2007): The design and evaluation of a hearing aid with trainable amplification parameters. Ear & Hear, 28(6): 812-830.
13. Van Tasell D, Sabin A, Franck K. (2014). User self-adjustment of a simulated hearing aid using a mobile device. Int Hearing Aid Research Conference, Lake Tahoe, CA, August.
14. Staab W, with Chasin M, Christensen L, Beck D, and Staples C. (2015).  Rants!  Some things we would change – if we could.  Hearing Review, Vol. 30, pp 14-17.
15. Comments of Bose Corporation. (2016). Van Tasell D. and Rabinowitz W.  Via Electronic Submission, to Division of Dockets Management (HFA-305) Food and Drug Administration, Docket No. FDA-2013-D-1295-0048, Regulatory Requirements for Hearing Aid Devices and Personal Sound Amplification Products: Draft Guidance for Industry and Drug Administration Staff: Reopening of the Comment Period.
16. Amlani, AM, Taylor B, Levy C, & Robbins R. (2013). Utility of smartphone-based hearing aid applications as a substitute to traditional hearing aids. Hearing Review, Dec: 17-22.
17. Humes L, Rogers S, Quigley T, Main A, Kinney D, and Herring C. (2017).  The effects of service-delivery model and purchase price on hearing-aid outcomes in older adults: a randomized double-blind placebo-controlled clinical trial.  American Journal of Audiology, Vol. 26, 53-79.
18. National Institute on Deafness and Other Communication Disorders (NIDCD). U.S. Department of Health & Human Services, National Institutes of Health (NIH). Model approach for over-the-counter hearing aids suggests verifiers similar to full-service purchase. March 2, 2017.  Referring to Humes research funded by NIDCD).  utm_source=NIDCDOther&utm_medium=referral&utm_term=GeneralPublic&utm_content=English&u tm_campaign=HumesHearingAids17)
19. Convery E, Keidser G, Caposecco A, Swanepoel de W, Wong LL, Shen E. (2013).  Hearing-aid assembly management among adults from culturally and linguistically diverse backgrounds: toward the feasibility of self-fitting hearing aids.  Int J Audiol. 2013 Jun;52(6):385-93. doi: 10.3109/14992027.2013.773407. Epub 2013 Mar 11.
20. Convery E, Keidser G, Hartley L, Caposecco A, Hickson L, Meyer C. (2011). Management of hearing aid assembly by urban-dwelling hearing-impaired adults in a developed country: implications for a self-fitting hearing aid. Trends Amplif. 2011 Dec;15(4):196-208. doi: 10.1177/1084713811431694. Epub 2011 Dec 26.
21. Keidser G and Convery E. (2016).  Preliminary observations of self-fitted hearing aid outcomes. The Hearing Journal, Nov. 2016 pp 35-38.