Audiological Diagnosis: The Need To Establish Ourselves

In the January/February issue of Audiology Today my colleagues Drs. David Lipscomb and Michael Seidemann and I discussed the role of audiologists in the ''diagnosis'' of hearing impairment (Roeser, Lipscomb and Seidemann, 2000). The impetus for this article was twofold. First, each of us (Lipscomb and Seidemann significantly more than I) have had the experience during court testimony as expert witnesses in litigation involving hearing loss of being challenged by attorneys that we (as audiologists) are not qualified to provide testimony about hearing loss. In essence, the argument goes, audiologists are not qualified to render an opinion regarding hearing loss, especially with respect to causation and further, audiologists are not physicians and the medical condition of hearing loss requires the opinion of a medical doctor. It is not specified that the physician be an otologist or an otolaryngologist per se; the only requirement is that the expert be a physician.

The ritual during court proceedings involves the opposing attorney objecting to testimony by the audiologist during the qualifying period. Following sidebar discussions, the judge typically renders his/her opinion. For the cases in which I have testified it has always been in favor of having me accepted as an expert, but with the objection of the opposing attorney.

The second impetus for preparing the statement in the Audioogy Today viewpoint article was that with my colleagues Drs. Holly Hosford-Dunn, Michael Valente and I had just finished a series of three multiple contributor audiology textbooks, one of which was on diagnostic audiology (Roeser, Hosford-Dunn and Valente, 2000). This diagnostic textbook consists of 26 chapters and covers the entire gamut of topics relating to diagnostic audiology. Included are chapters on: the anatomy and physiology of the peripheral and central auditory systems, vestibular system diagnosis and disorders; radiology; brain imaging; pharmacology; psychoacoustics; calibration; pure tone and speech tests; central tests; ENG evoked potentials; neonatal screening; the genetics of hearing loss; and more.

Although the complex nature of diagnostic audiology is a well-known fact to me, having had first-hand exposure to the array of diagnostic material in the textbook which was just published under our editorship made me realize the sophisticated level that audiology has reached. It is now necessary for audiologists to have comprehensive knowledge and in-depth experience to administer and interpret diagnostic audiological tests. Audiologists, through their formal training and clinical experience, have this requisite knowledge and experience. Moreover, it is the audiologist who is on the front-line administering audiologic procedures, interpreting test results, counseling patients and referring and/or applying audiologic therapies for the vast majority of the time. Yet, it is apparent that audiologists are challenged by outside entities when it comes to diagnosing hearing loss/impairment.

Audiologists spend several years obtaining formal education and clinical experience being exposed to hearing science, acoustics, anatomy and physiology of hearing, hearing disorders, diagnostic audiology, counseling patients, rehabilitative audiological procedures including hearing aids, assistive listening devices, alternative communication models and many other devices and related topics. No other professional has the extensive background in hearing and hearing disorders.

In fact, in most medical schools, audiologists are responsible for providing the didactic and clinical material to the otolaryngology residents. The typical otolaryngology resident receives several formal lectures on interpretation of audiological test results and additional material is presented on basic hearing science and acoustics. Much of the clinical audiological training obtained by the otolaryngology resident is obtained through patient interaction alongside an audiologist-mentor.

This is not to say that audiologists are capable of rendering medical opinions; they are not. Medical opinions are beyond the scope of audiological practice. As an example, on the basis of determination of a conductive component an audiologist cannot inform a patient that surgery is needed and that hearing will be restored to normal limits. However, it may be stated that surgery may be indicated and, if it is successful, will improve hearing to normal levels.

The point of this brief commentary is to reinforce the principle that audiologists do have the necessary training and experience to diagnose hearing loss; audiologists can provide an audiological diagnosis. The basic distinction between conductive, sensorineural (and the distinction between sensory and neural) and mixed hearing loss is well within the scope of audiological practice. The distinction between cochlear, VIIIth nerve and central findings are certainly within the scope of audiological practice. Additionally, relating audiological findings to possible causation is certainly within the scope of audiological practice. Audiologists should have the confidence to defend their ability to provide diagnostic information and an audiological diagnosis.
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Roeser, R. J., Hosford-Dunn, H. and Valente, M. (Eds) (2000) Audiology: Diagnosis. Thieme Medical Publishers, Inc., New York: NY.

Roeser, R. J., Lipscomb, D. and Seidemann, M. (2000) Viewpoint: Audiologists & Diagnosis. Audiology Today, 12 (1), 13-14.