Inside the Research | December 2020 Hearing Review

By Douglas L. Beck, AuD

Brian Taylor, AuD, has been a clinician, educator, and executive in hearing healthcare for over 25 years, and he currently serves as the Director of Scientific and Product Marketing at Signia. Dr Taylor is also a relied-upon and prolific author and blogger on clinical issues and practice management, including a recent update to one of his most popular texts, Fitting and Dispensing Hearing Aids (Plural Publishing)1 which he co-wrote with Gus Mueller, PhD. We thought this would be a good time to catch up with him and get his perspectives on this subject.

Beck: Hi Brian! Congratulations to you and Gus on the third edition of Fitting and Dispensing Hearing Aids. I read it, I liked it, and I wholeheartedly recommend it for undergraduates, hearing aid dispensers, and audiologists.

Taylor: Thanks Doug. I appreciate that.

Beck: So the first question is why did y’all decide to write a third edition? It seems like an incredible commitment of time and energy, and as we know, writing is not easy or quick!

Taylor: Agreed. Writing is always more time-consuming than one originally plans on. Nonetheless, I am so grateful to have such a creative and talented co-author as Gus. Even though the second edition is only 4 years old, hearing aids continue to change and evolve, so we had some updates.

Beck: I’m glad you guys decided to push forward! Who was the target audience for the third edition?

Taylor: As you mentioned earlier, undergraduates, hearing aid specialists, audiologists, students, and various hearing care professionals across the globe. We try to provide the reader everything they need to know—all in one place—to fit their first pair of hearing aids.

Beck: Brian, let’s start with a controversial issue. Some of our colleagues have indicated “all hearing aids are the same” which makes absolutely no sense to me. But it’s your interview! What are your thoughts?

Taylor: Well, the statement “all hearing aids are the same” doesn’t make sense to me, either. First, it’s true that all hearing aids share some basic technologies, like all cars and trucks have tires, batteries, and steering wheels. Within modern hearing aids, regardless of technology level or brand, we’ll usually find sophisticated signal classification systems, multiple channels of compression, complex noise reduction algorithms, automated directional microphone technology, and vastly different types of wireless capabilities.

I think what’s interesting is how each manufacturer combines and implements these technologies and features in unique ways. Many of the differences you see across manufacturers on these key features reflect their philosophy on how to address common wearer problems like speech understanding in noise. Our book tries to cut through the jargon manufacturers use to describe what’s inside their “black box.”

Beck: And arguably, the most important factor is the hearing care professional (HCP), their skill, knowledge, and their ability to select and fit the best instrument to meet the specific needs of the patient, in accordance with Best Practices.

Taylor: Absolutely. In fact, I agree with your emphasis about how using the Best Practices endorsed by AAA, ADA, or IHS will maximize the quality of whatever device is chosen. The sound quality and performance of all hearing aids are pretty good these days, but it’s up to the HCP to optimize patient outcomes through customization of the fitting and counseling process.

Beck: I totally agree. My belief is we need to be in compliance with nationally recognized best practices from AAA, ASHA, or IHS. However, interviews with Dr Mueller from 20172 and a recent 2020 interview with Dr Michael Valente3 indicate that quite often hearing aid fittings may still be done without verification and validation, which is not in compliance with today’s best practice models.

Taylor: Gus and Mike have been talking about those topics for about 40 years, and they are exactly right. I don’t have anything more to add except to say that many hearing aid manufacturers have automated real-ear measures within their fitting software, making it an even faster procedure to complete during an appointment—plus with a RECD measure from a patient you could even perform remote verification. Those are important developments, and they’re topics we cover in the book. 

Beck: And when we talk about outcomes, we have to be sure to go deeper than simple measures of audibility. You often remind professionals that we must optimize audibility, and I agree. However, audibility by itself is simply not enough. Nobody listens to conversations or music at their threshold levels! We need to assure an appropriate signal-to-noise ratio (SNR), too, so the person wearing the hearing aids can listen comfortably. Using a patient-centered approach, we realize patients want more than hearing; they want listening—the ability to untangle sound and assign meaning to the sounds they hear, to understand speech in noise.

Taylor: I believe what you’re getting at Doug is the need to personalize noise reduction and other technology to meet the demands of the individual. These days, as you know, hearing aids have many different types of noise reduction algorithms and directional microphone systems, and each manufacturer combines and implements these features differently. In addition to using probe-mic measures to verify the performance of these features, and demonstrate to the patient how they work, it’s important for HCPs to collaborate with patients on a set of functional goals, align patient expectations to these goals, teach patients how to be better listeners with their hearing aids, and verify and validate outcomes. Hearing aid technology, although it has never been better, doesn’t do all this work; professionals do.    

Beck: In fact, Consumer Reports (CR) in January 2019 told consumers to expect real-ear probe-mic measures when purchasing hearing aids.4 CR said: “Ask your hearing aid provider to do a real-ear test, also called a real-ear measure. This involves placing a thin probe in your outer ear while you wear your hearing aid—to measure whether your hearing aid is responding appropriately to your level of hearing loss. He or she should also test your understanding of speech in quiet and noisy areas.” Of course, AAA, ASHA, and IHS say the same thing, so it shouldn’t be a surprise to anyone.

Taylor: Your comment about getting the message to consumers about the value of real-ear measures (REM) reminds me of the outstanding work Dr Cliff [Olson] has done in this area with his YouTube videos. He has a really good post about REM.5 Your comment also reminds me there are important differences between verifying the performance of a hearing aid and validating the satisfaction or benefit of one. We cover these concepts in the book in two separate chapters and include some of the newer self-report measures of patient outcome.

Beck: I noticed and was glad to see you mention the “Count the Dots Audiogram” by Killion and Mueller6 which allows us to quantify and discuss hearing loss simply, quickly, and importantly in terms of percentage. The HCP never has to mention or define decibels! I totally agree with that approach and I’ve been endorsing it since 1990.

Taylor: The Count the Dots Audiogram is a useful training tool for HCPs because it shows how much various frequencies contribute to speech understanding. It reminds me how important it is to have a smooth wideband frequency response in hearing aids and how easily patients can understand hearing loss when we use terms they intuitively understand like percentage. We use percentage of hearing loss in the AAO-HNS and ASHA hearing loss formulas, in the Speech Intelligibility Index (SII), in the audibility and articulation index and more…so using percentage as detailed in the Count The Dots Audiogram makes it very simple and easy to understand. In that same chapter, we discuss the SII, which is another useful tool for understanding the relationship between restoring audibility and how it relates to intelligibility.

Beck: That chapter is one of my favorites because you not only offer quite a few listening and communication assessments and how to use them, but you offer glorious detail regarding speech-in-noise (SIN) testing and you review the basics one needs to know about speech audiometry.

Taylor: Yes, I think that’s a really useful chapter.  I’m not sure if the details are glorious. Maybe that’s a question for Gus!

Beck: If you don’t mind, can you review the information about how to test, and how not to test, word recognition?

Taylor: Well, the short answer is clinicians need to do word recognition testing correctly. The right intensity level, the right number of words per ear, and the right mode of delivery. Many in the profession don’t even call it the right name! It’s a recognition test, not a discrimination test. When speech audiometry is poorly conducted it can drive up the cost of healthcare, create unnecessary patient anxiety, and lead to erroneous clinical decisions. Doing it correctly means following the science and taking the time to learn how to conduct the test using valid methods. We address those details in that chapter.

Beck: Can you talk a little bit about the accuracy of the word recognition lists?

Taylor: The value of doing speech audiometry correctly is the ability to make better, more accurate decisions based on the results. In Chapter 4, we detail a useful tool called the SPRINT. It’s an acronym for SPeech Recognition INTerpretation. The SPRINT was created by Linda Thibodeaux7 at Callier/UTD several years ago and it’s based on the work of Judy Dubno from the 1990s. The SPRINT chart8 allows you to know when a difference between two scores is significant. You can use the SPRINT to find when a word recognition score is disproportionately low relative to the pure-tone average from the audiogram for the same ear. You can also compare word recognition scores between ears to find which differences are significantly different. It’s a really handy tool, but it doesn’t work if you don’t conduct speech recognition testing correctly by following the science.

Beck: What else do you add to the third edition of the book?

Taylor: As you know Doug, over-the-counter and self-fitting hearing aids are hot topics these days. We devote some attention to them and how they might differ from conventional hearing aids. In addition, we’ve fully updated information on machine learning in hearing aids and the various types of wireless connections inside a hearing aid.

The one thing that has not changed in any of the three editions of this book is that each chapter is devoted to a theme. If you like country music, cooking, drinking wine, or watching movies you might find those chapters informative and maybe a little entertaining—and, when was the last time you read an entertaining textbook!

Beck:   Excellent point—it is entertaining! Okay Brian, I think our time is up. I really like and highly recommend the third edition of your book. Congratulations!

Taylor: Thanks Doug.

References

  1. Taylor B, Mueller HG. Fitting and Dispensing Hearing Aids. 3rd Ed. San Diego: Plural Publishing:2020.
  2. Beck DL. Speech mapping and probe microphone measurements: An interview with Gus Mueller, PhD. Hearing Review. 2017;24(8):38-39. Available at: https://hearingreview.com/hearing-products/testing-equipment/speech-mapping-probe-microphone-measurements-interview-gus-mueller-phd
  3. Beck DL. An Interview with Michael Valente, PhD: Considerations after 45 Years in Audiology. Hearing Review. 2020;27(9):26-28. Available at: https://hearingreview.com/inside-hearing/research/an-interview-with-michael-valente-phd
  4. Consumer Reports. Hearing Aid Buying Guide. 2020. Available at: https://www.consumerreports.org/cro/hearing-aids/buying-guide/index.htm
  5. Olson C. The most important hearing aid video you will ever satch! | What is real ear measurement? December 18, 2017. Available at: https://www.youtube.com/watch?v=cHR0Oa6I-wY
  6. Killion MC, Mueller HG. 20 years later: A new count-the-dots method. Hear Jour. 2010;63(1):10-17.
  7. Thibodeau LM. Speech audiometry. In Roeser R,  Valente M, Hosford-Dunn H, eds. Audiology: Diagnostics. New York: Thieme Medical Publishers: 288-313.
  8. Thibodeau LM. Speech Recognition Interpretation Chart. 1999. Available at: https://www.utdallas.edu/hhlab/files/sprint-chart-25.pdf
Douglas Beck, AuD

About the author: Douglas L. Beck, AuD, is the Vice President of Academic Sciences at Oticon Inc, Somerset, NJ. He has served as Editor in Chief at AudiologyOnline and as Web Content Editor for the American Academy of Audiology (AAA). Dr Beck is an Adjunct Clinical Professor of Communication Disorders and Sciences at the State University of New York, Buffalo, and also serves as Senior Editor of Clinical Research for The Hearing Review’s Inside the Research column. 

Citation for this article: Beck DL. Fitting and dispensing hearing aids: An interview with Brian Taylor, AuD. Hearing Review. 2020[Dec];27(12):14-15.