Abstract
A total of 42 selected patients with hearing impairment of purely perceptive type and with definite recruitment by Metz's test compared a behind-the-ear hearing aid with amplitude compression amplification and a behind-the-ear hearing aid with linear amplification over a trial period of at least 2 months, the instruments being tested by alternating use. Not quite one-third of those studied (13 patients) chose the compression amplifier hearing aid, while the remainder preferred the conventional amplifier. The subjective evaluation revealed only minor differences between the two types of apparatus. Neither a determination of the dynamic range of the ear by measuring the sensation level of the acoustically elicited middle ear muscle reflex, nor a determination of the dynamic range for intelligible speech on the speech audiogram, appears to be suited to predicting which patients should have treatment by means of compression amplification.