The audiogram is a common, every day tool for many. Jame Jerger, PhD, wrote about the history of the audiogram for The Hearing Review. Let’s take a look at how it came to be.
The first audiometer in the U.S. was developed in 1919 by Cordia C. Bunch who later became a professor at Northwestern University teaching courses on hearing testing and disorders – even mentoring the “Father of Audiology” Raymond Carhart. However, this first audiometer was only used in a private practice by one particular doctor and not publicly available. Mr. Bunch used many of the audiograms derived from his tool for research and his writings.
After World War I two physicists, Harvey Fletcher and R.L. Wenger, developed the commercially available Western Electric Model 1-A audiometer. They worked with Dr. Edmund Fowler an otolaryngologist to clinically test it. The big question for each of them was how to standardize the reporting of audiometric thresholds on what we call today the audiogram.
The audiogram’s horizontal scale of frequency never received much questioning. Dr. Jerger writes, “There was never a serious issue concerning representation of the frequency scale; the well-established musical scale, in which octave intervals are equally spaced, was readily adopted for the horizontal dimension of the graph. But the vertical dimension, the representation of threshold intensity, underwent a number of iterations.” The vertical access has had many changes from a “Percent of Normal Hearing” approach first advocated by the otolaryngologist Dr. Fowler to “Hearing Loss – Sensation Units” developed by the physicist Fletcher to what we call today “Hearing Level in dB”.
Just as hearing aids have evolved over time, so have our patient care practices and diagnostic tools. In your own practice, how do patients first react when they see their audiograms? How do you break down the results into words they can best relate to? Share with us how this visual tool helps you explain hearing loss.