Telephone Screening for Hearing Loss Questioned by ASHA

Test signals are limited to frequencies below 3000 Hz (cycles per second) so that hearing at higher frequencies is not screened. Also, the physical nature of the signal that is actually heard depends on factors, such as the telephone answering machine used to conduct the tests, the telephone transmission lines, the model of telephone used by the caller, background noise, the response of the telephone for that particular call, and even the position of the telephone receiver relative to the listener's ear.
Because of these factors, two persons calling the same telephone screening number from different telephones may receive somewhat different tests. In fact, the same person using the same telephone may not receive exactly the same test each time he or she calls.