Test/retest reliability of distortion-product and transiently evoked otoacoustic emissions.

Otoacoustic emissions can be used to study cochlear function in an objective and noninvasive manner. These features of emitted responses have stimulated a great deal of investigation into the utility of evoked emissions as clinical tests of hearing. One practical and essential aspect of any clinical measure is the consistency of its result upon repeated testing of the same individual (i.e., its test/retest reliability). The goal of the present work was to conduct a systematic study of the test/retest reliability of the two evoked emission types, the transiently evoked and the distortion-product otoacoustic emissions, that have the greatest promise of becoming clinically useful. Toward this end, the short- and long-term reliabilities of these two response measures were examined in 12 normally hearing adults. The results of these experiments showed that the consistency of both measures of evoked otoacoustic emissions was generally excellent.