Many of us make a living doing hearing tests and fitting hearing aids. Unfortunately, the diagnostic tests we use were developed to provide a medical evaluation of hearing. They were not designed with rehabilitation in mind. Conventional hearing tests provide a lot of useful information, but they do not give us a sufficient perspective on how best to help the patient. Therefore, we need to modify our tests so we know how to program a patient’s hearing aids most efficiently for each listening situation.
We acquire most of our hearing aid fitting skills through years of experience and from our struggle to solve hearing-related problems. Sometimes the most important aspect of the fitting is to keep it simple. Other times, patients’ hearing is so poor they are becoming cut off from their friends and family. In these cases, we give the patient extra sound in the lower frequencies to increase the “richness” of the sound and to provide the emotional cues in the very low frequency zone. Or, we adjust the gain and frequency response to maximize basic word-understanding ability.
We are constantly working with, and appraising, all aspects of the patient’s hearing. Sometime we use conventional words as the test items. Or we may put the hearing aid into an analyzer and measure the instrument’s performance. At times, we need to evaluate the patient’s ability to hear when it is noisy. Modern hearing aids have multiple programs, so we need to adjust and test them to make sure the instruments are working correctly in all listening situations.
THE REAL-WORLD VIRTUES OF LIVE SPEECH
Most audiology training programs teach students the proper way to administer each test. In these classes, we learn the advantages of using recorded voice tests (less variability, more consistency between offices, etc.). But, in the real world, I never have time to do “recorded voice” testing and, to be honest, I don’t believe recorded voice testing is needed or even useful.
When I start a test or a demonstration, I have to find out quickly if the patient understands the test words. If I need to make the test easier, I switch to two-syllable words; if I need to make it more difficult I switch to monosyllables or rhyme words. In a way, I am practicing like a speech scientist, but one who works with hearing aids.
Test words are my tool for determining the adequacy of the amplification. Using words as test items I can quickly and efficiently find the patient’s zone of functional hearing and the zone where the patient has very poor hearing or none at all. Test words give me insights into how the hearing aid is performing in the lower, mid, and higher frequencies. For example, words like “blue, new, brown,” are low-pitched in nature, while “ice, swim, beach” are high-pitched. If a patient wearing recently fitted hearing aids set to the normal listening level misses words like “new” and “brown,” that probably means I need to add gain in the lower frequencies.
The same concept is true for high-pitched words and high-frequency gain. Using “live speech” gives me large amounts of information in just a few seconds. Plus, the patient and the family always know what you are doing: You are addressing the most common complaint: “I hear, but I don’t understand the words.”