By Harvey Abrams

This post appeared at Hearing Views exactly five years ago (March 7, 2012). It bears another visit as a refresher course to remind audiologists of our tools of the trade and the intent of their applications.  The timing of the refresher course is especially apropos as we near the end of the “lull” mentioned by Dr Abrams last week in Hearing Economics, where he called for audiologists to use “income and outcome” measures as a means of differentiating and separating our services in the commoditized hearing aid market.  

The lull is a good time to brush up.  It’s likely the quiet before the storm, what with the upcoming FTC Workshop on Hearing Health Technology on March 18, followed by Audiology Now! 2017, and in the midst of fascinating new research on hearing aids dispensed by different means. 

 

Harvey Abrams

In a recent MarkeTrak report, Kochkin and colleagues (2010) provide compelling evidence suggesting that our patients’ level of real-world success is directly related to the extent to which their hearing care provider follows a best-practice protocol for the selection and fitting of hearing aids.

This protocol has been detailed in clinical practice guideline documents (e.g., American Academy of Audiology; AAA, 2006) and is currently taught in most AuD training programs. Two key elements of these guidelines are verification and validation. However, there appears to be some confusion among clinicians as to how these two are distinguished from one another. To state it simply, verification is a device-centric process whereas validation is patient-centric.

 

THE VERIFICATION PROCESS

Verification is the process by which we determine the extent to which the device meets a set of measurable specifications or expectations. This process may include measuring the response of the hearing aid in a test chamber (the coupler response) to make sure (verify) that the hearing aid that we received from the manufacturer and the specification sheet that accompanied that hearing aid are reasonably well matched. It’s important to verify that what we received is what was sent. We might think of this process as a quality control measure.

The probe-tube measurement battery is the other verification process in a best-practices protocol. Here, we’re checking (verifying) the extent to which the hearing aid is meeting a set of pre-determined gain or output levels (targets) as measured in the ear canal. We know that the same signal in different ears (or different hearing aids in the same ear) can have dramatically different frequency/gain characteristics (and will almost certainly differ from the coupler response), so we need to measure the hearing aid response in real time in the actual ear to get an accurate measure of the hearing instrument’s gain and output characteristics.

We should also remember that there is more to the “real-ear” verification procedure than simple target matching. We also want to verify that the output of the hearing doesn’t exceed our patient’s discomfort level; that compression is occurring at the level set in the software; that the directional performance is what we expect; that the feedback-cancellation algorithm is effective; and that noise reduction is functioning properly.

Not all measures need to be conducted in the ear to verify the response, however. Pediatric audiologists are familiar with the technique of fitting the hearing aid in the coupler after measuring the difference between the coupler’s response and the child’s ear canal response (the real-ear-to-coupler difference or RECD). Only one measure (the real-ear unaided response) needs to be made in the ear; all the other verification measures can be made in the test chamber, much to the relief of both the child and the audiologist.

But what if my fitting software displays a close match between the real-ear target and the hearing aid response? Does this mean that I’ve verified the fitting?

No, it doesn’t. You may have verified the quality of the software, but not necessarily the fitting. The aided targets displayed in the fitting software are based on an average ear canal response and a predicted hearing aid response based on style, venting, and canal length characteristics. To the extent that the patient’s ear canal deviates from the average and the hearing aid characteristics deviate from what is predicted, the hearing aid may over- or under-amplify at one or more key frequencies, resulting in inadequate audibility, compromised quality, or uncomfortable loudness.

 

THE VALIDATION PROCESS

But what if I successfully verify my hearing aid’s performance in the coupler and in the ear? Can I be assured that my fitting will be successful?

I’m afraid not–and this is where validation comes in. Recall that validation is patient-centric. It is the process by which we measure the extent to which the treatment goals have been achieved–as perceived by the patient.

Fortunately, we have many validation tools available to us, although they don’t all measure the same thing. I tend to classify measures such as the Hearing Handicap for the Elderly (HHIE; Ventry and Weinstein, 1982) and the Abbreviated Profile of Hearing Aid Benefit (APHAB; Cox and Alexander, 1995) as indirect validation measures. While these questionnaires certainly measure benefit as perceived by the patient, we don’t know how much importance the patient assigns to the situations described in the questionnaires.

Direct validation measures, such as the Client Oriented Scale of Improvement (COSI; Dillon, James, and Ginis, 1997) or Glasgow Hearing Aid Benefit Profile (GHABP; Gatehouse, 1999) are designed in such a way as to facilitate the identification of those communication situations that cause patients their greatest frustration and those that they most want to resolve. By measuring the extent to which those “most critical” situations are perceived by our patient as being resolved following treatment, we validate the relative success of our intervention. That intervention, of course, may (and often should) include more than just amplification. By establishing treatment goals up front, we can identify the need for such interventions as assistive technology, auditory training, and group hearing rehabilitation.

What about measuring aided speech recognition in quiet and in noise? Are those considered validation methods? While we are measuring patient-specific benefit, we don’t know the extent to which, for example, a 15% improvement in speech recognition in quiet or a 2-dB improvement on the Hearing in Noise Test (HINT; Nilsson, Soli, & Sullivan, 1994) performed in the clinic will resolve our patient’s real-world communication difficulties. Consequently, we really can’t consider these in-clinic performance measures as validating the success of our treatment.

 

VERIFICATION AND VALIDATION ARE BOTH ESSENTIAL

In summary, verification and validation are associated with different aspects of a best-practices hearing aid selection and fitting protocol, but each is essential to ensure a successful treatment outcome.

 

Harvey Abrams, PhD, is the Director of Audiology Research at Starkey Laboratories. Previously, Dr. Abrams served in clinical, research, and administrative capacities with the Department of Veterans Affairs and the Department of Defense. He also teaches distance-learning courses for the University of South Florida and University of Florida.  He received his master’s and doctoral degrees at  the University of Florida. His research has focused on treatment efficacy and improved quality of life associated with audiologic intervention. He has authored and co-authored several recent papers and book chapters and frequently lectures on outcome measures, health-related quality of life, and evidence-based audiologic practice.

 

REFERENCES

  • American Academy of Audiology (2006): Guidelines for the audiological management of adult    hearing   impairment. Audiol Today 18:32-36.
  • Cox R, Alexander G (1995):  The Abbreviated Profile of Hearing Aid Benefit. Ear Hear 16:176-186.
  • Dillon H, James A, Ginis J (1997): Client Oriented Scale of Improvement (COSI) and its relationship to several other measures of benefit and satisfaction provided by hearing aids. JAAA 8:27-43.
  • Gatehouse S (1999): Glasgow Hearing Benefit Profile: Derivation and validation of a client-centered outcome measure for hearing aid services. JAAA 10:80-103.
  • Kochkin S, Beck DL, Christensen LA, et al. (2010): MarkeTrak VIII: The impact of the hearing healthcare professional on hearing aid user success. Hear Rev 17:12-34.
  • Nilson M, Soli S, Sullivan J (1994): Development of the Hearing in Noise Test for the measurement of speech reception thresholds in quiet and in noise. J Acoust Soc Am 95:1085-1099.
  • Ventry I, Weinstein B (1982): The Hearing Handicap Inventory for the Elderly: A new tool. Ear Hear 3:128-134.

 

By Jerry L. Northern, PhD

  

A Life in Audiology is a fascinating new autobiography written by Dr. James Jerger in which he describes his interesting life story and personalizes his career as our foremost audiologist.  In a very readable 144 pages, Dr. Jerger recounts his early years growing up in Milwaukee, Wisconsin, his brief stint in the Army, and his education at Northwestern University.  Subsequent chapters detail his research and mentoring activities at Northwestern, Gallaudet University and the Veterans Administration in Washington, DC, as well as his 35-year career at the Baylor College of Medicine in Houston, and his electrophysiological research at the University of Texas/Dallas.  Other chapters describe his world travels, his numerous honors and the many friends he made during his career. Of special interest are the many descriptions of his interactions with internationally noted hearing specialists and their roles and impact on his clinical and research activities.  With a bit of tongue-in- cheek, Dr. Jerger describes his book as “…an account of some positive achievements, scattered among mistakes and blunders” in his life.  The book jacket describes the book as a “…. unique and engaging account of an inspiring scholar’s remarkable career and the profound effect his work has had on the field of audiology.

At the invitation of HTTM, Dr. Jerger agreed to participate in an interview about his autobiography, his career in audiology, and his current thoughts about the audiology profession in which he has been the cornerstone for nearly 60 years. 

 

JN: Congratulations, Jim, on the publication of your autobiography. What prompted you to write this book?

JJ. Jerry, I wanted students, young audiologists, and anyone contemplating the field, to know how rewarding our profession can be. I wanted to give them a sense of the wide opportunities that await them and their real chance to make a difference. It was also my way of thanking the many students and colleagues I have been privileged to know and work with. The book provided an opportunity to share my career experiences of more than 60 years, and in a way, it is a summary of my accomplishments and lessons learned as a professor, clinician, scientist, and my life dedicated to the understanding of hearing and the measurement of hearing impairment.  And, a thanks to Rich Tyler of the University of Iowa for suggesting the idea for this book. 

 

JN: Among the founders of our profession, whom do you admire most?

JJ:  Without a doubt, Cordia C. Bunch. I never knew him. He died well before I entered Northwestern as a student, but he was surely the first genuine clinical audiologist. In the 1920s and 30s, with no more than a Western Electric 1A audiometer he personally gathered, evaluated and assessed the air conduction audiograms of all the patients flowing through the ENT practice of Dr. LW Dean, for two decades, first in Iowa City, then in St Louis. In the process, he learned a good deal about hearing loss, wrote many articles and books about his findings, his conclusions, and his incredible insights so many years ago.  His work gave birth to audiology as we know it and we have all benefited from his insights.

 

JN: During your career, which development was most important in our effort to diagnose auditory pathology?

JJ:  Unquestionably, it was the auditory brainstem response. It made possible the hearing screening of every newborn baby, and provided, for the first time, a marker of the status of the auditory pathways in the lower brain stem. This has benefited us in more ways than I can enumerate and opened up so many avenues of research that were not previously possible. 

 

JN: What do you think is the most important research need right now?

JJ: That usually depends on your field of interest. For me it is aging. So many chapters seem to be unfolding. New on the horizon, for example is the phenomenon of binaural interference. A small but significant number of elderly people with hearing loss insist that they do better with one hearing aid than with two. It is a significant issue. One entire pathway of input to the binaural processor does not seem to be working correctly. What is going on? How is it related to age, how is it related to degree of loss, how is it related to interaural asymmetry of loss, how is it related to the inevitable cognitive changes that occur with age?  Here is a gold mine for researchers that has hardly been tapped. We do not need more studies of how many people have it. What we do need is answers to the “why” question, and this will only come from individual intensive case studies of the people who actually have it.  Research in this area will, I am confident, reinforce the audiologists’ role in recommending the most appropriate system of amplification for the client.

 

Q: You have made amazing contributions by writing and publishing more than 300 scientific papers. Do you have a favorite journal publication?

A: Well, actually I have two favorites. The first is “Clinical Experience with Impedance Audiometry”, which was published in the Archives of Otolaryngology in 1970. It has been quoted more than 700 times and continues to be cited after almost 50 years. It is now a citation classic. The second is “Why the Audiogram is Upside Down”, which appeared in the International Journal of Audiology in 2013. No paper was more fun to write.

 

JN:  Who were the most important people in the formative years of your career?

JJ:  Well, at the top of my list I would place my wife, Dr. Susan Jerger, who has been a source of support and inspiration for more than 50 years. Next would be my Milwaukee Riverside High-School Latin teacher, Mr. Merton S. Lean.  He brought a dead language alive for me, and brightened two memorable summers for me at Camp Red Arrow for Boys in northern Wisconsin.  

At Northwestern University I would include Dr. William McGovern who taught Philosophy in the Guise of Political Science, and Drs. Myklebust, Gaeth and Carhart, who launched me on my career in Audiology. At the Baylor College of Medicine, where I thrived for 35 years, there was no stauncher supporter than Dr. Bobby Alford, Chief of Otolaryngology and Head of Otolaryngology at The Methodist Hospital. Otolaryngology residents who later became close friends included Mickey Stewart and Gail Neeley.

Among the several graduate students at Baylor, Brad Stach stands out for many reasons, but especially our collaboration in launching the American Academy of Audiology.  Fellow audiologist and co-author Rose Chmiel contributed in so many ways. 

At the School of Behavioral and Brain Sciences at the University of Texas/Dallas it was a privilege to serve under Dean Bert Moore, a true gentleman and scholar, and to work with graduate students Ralf Greenwald and Jeff Martin.

 

James Jerger, Tahiti, 1970s

JN: I know that sailing has been a big part of your outside interests and in your book you relate an interesting story of your boat capsizing with Rufus Grason on board in Galveston Bay.  Tell us how did you get into sailing and what kind of boats did you sail?

JJ: We started with a 10-foot dinghy. With the aid of several books we taught ourselves the basics of sailing on Lake Houston, then moved up to a genuine 12-foot sailboat of doubtful parentage. We sailed it mostly on Lake Summerville, just north of  Brenham, Texas, but with an occasional foray into Galveston Bay. This gave way to a 16-footer that we sailed mostly on Galveston Bay. On one of these trips we saw our first dolphins as they trailed the vessel from  the Gulf of Mexico into  Galveston Bay.

As our confidence grew we traded up to a Balboa 20 which had a real cabin that you could sleep in. We could still trailer this boat up to lake Summerville or down to the Bay, but setting it up from the boat trailer was not trivial, so we rented a berth, first at Lake Summerville, then down to the Bay at the Watergate Yachting Center on Clear Lake. From here it was a major step up to an Ericson 27 with a genuine inboard engine.  This opened the possibility for new sailing experiences, including a trip down the intercostal waterway to Freeport, TX. 

Susan Jerger sailing in the 70s

When we outgrew the Watergate we moved the craft to the Seabrook Shipyard, closer to the entrance to the Galveston Bay. The only problem with the Ericson was lack of air conditioning. If you think this is evidence of an effete withdrawal from the outdoor experience, you have never lived in Houston, Texas, where the heat and humidity rival the Amazon basin. We found a used Cal 34 with built-in air conditioning and a new life opened. Now we could spend nights on the boat in total comfort.  Well, if you are an upwardly mobile sailor the next step is inevitable. We joined the Lakewood Yacht Club on Clear Lake and spent many happy weekends in that luxurious setting before moving to the Dallas area where opportunities for serious sailing were sparse.

In some of our travels far from home we took the opportunity to charter for up to a week. Our favorite charter was wandering through the San Juan Islands out of Bellingham Washington in 1984. I was there at Western Washington University doing a two-week course for the summer term. I had been invited as second choice after their first pick, a fellow named Jerry Northern, had turned them down. We also chartered in Tahiti, in Sweden, in San Diego, and in Wisconsin’s Green Bay on Lake Michigan. And I cannot leave the subject of sailing without mentioning very enjoyable trips on Chesapeake Bay as a guest of the Cindy Compton-Conleys.

 

JN: You were instrumental in forming the American Academy of Audiology in 1988.  You describe the formation of our own professional organization as an “…accident of history.”  You also state that “The first year of the Academy’s existence was an uncertain time.  The founders were not at all sure that their effort would succeed.”  How do you feel about the Academy of Audiology after more than 25 years?

JJ: On the one hand it has given us the independent professional home we so desperately needed by the 1980s.  I have been pleased by the growth of the Academy over the years and ever proud that I played a role in its creation.  And, clearly it has been a strong force in uniting the various specialty groups within the profession. On the other hand, it now seems to be serving the interest of an ever-narrowing segment of us. I worry about that.

 

JN:  It was an important event in the history of audiology when you set the stage and started the very first AuD program in the U.S..  How do you think the clinical doctorate degree has worked out?

JJ:  I was anxious to get our program started because I felt that it was necessary before we could become a doctoral level health-care-profession, dependent on neither speech pathology nor otolaryngology. We have come a long way in that direction, and it is certainly the case that the AuD has played a pivotal role. I am increasingly concerned, however, that there are too many small AuD programs in which the kind of broadly based training that we had initially envisioned is just not possible. I continue to believe that a smaller number of larger programs would be much better in the long run.

  

JN: What is your advice to young audiologists just getting started in their studies or careers?

JJ: Keep your options open. Do not allow yourself to be seduced by the lure of immediate monetary reward. The main thing is to enjoy what you are doing and to do it at the highest possible level of excellence.

 

JN:  Do you have any concerns about our profession or what are your thoughts about the future of audiology?

JJ: We are at a crossroads. The winds of change can carry us to new heights or to new lows. I think it is clear that, unlike every other health care profession, we have become too involved in the sale of a product, to the detriment of the research and diagnostic arenas that made the profession grow and was interesting to so many of us in the early years. Barry Freeman asks us to return to our roots, and I could not agree more. We need less emphasis on product sales and more emphasis on the provision of complete audiological services.   If we choose the right path at this crucial moment in time, we can maintain our position as one of the premier health care professions.

 

JN:  And finally, Jim, we would all like to know what are you doing these days in your retirement?

JJ:  Well, I actually ‘retired’ in 2014 when we moved from Dallas and resettled in Portland, OR.  I am currently doing quite a bit of writing. I did a piece on “Remembering Raymond Carhart” recently for Audiology Today, and a reminiscence of a memorable trip I took to Germany, Denmark and Sweden in 1960, which appeared in Hearing Review.  And, as we have brought out in this interview, I have just completed an autobiography, “James Jerger: A Life in Audiology” which is available from our good friends at Plural Publishing in San Diego.

Finally my colleagues at Brooklyn College, Shlomo Silman, Carol Silverman, and Michelle Emmer, and I have just completed an article on binaural interference, in which we offer suggestions for how to approach further research in this arena.

 

JN:  Thank you, Dr. Jerger….as always it is a pleasure to talk with you.   I would like to remind all attendees at the 2017 AudiologyNow convention in Indianapolis that you will have an opportunity to meet and talk with Dr. Jerger on Thursday, April l7th, at 10:30 am and 1:00 pm.  Attendees will be able to review copies of his autobiography, and purchase personalized signed copies of “James Jerger: A Life in Audiology.”  The book may also be ordered online through Plural Publishers, Inc., $34.95).

 

Jerry Northern PhD

Jerry L. Northern, PhD, is Professor Emeritus at the University of Colorado School of Medicine where he served as head of the Audiology Department for more than 26 years. Dr. Northern, a native of Denver, is a prolific writer and editor of several professional journals; he has authored a dozen textbooks in the areas of hearing and hearing disorders, including six editions of Hearing in Children and three editions of Hearing Disorders. Internationally known for his expertise in pediatric audiology, his professional background includes clinical practice, teaching, medical-legal industry experience, clinical and basic research, as well as consulting in nearly 30 countries. Dr. Northern is a founding member of the American Academy of Audiology and served as the organization’s third president. He has been honored by numerous organizations for his contributions to the field of audiology. He has also authored numerous posts for HearingHealthMatters, including a prescient series in 2014 entitled The Unraveling of Hearing Healthcare Delivery Part 1 and Part 2.