Masked high-frequency bone-conduction audiometry: test reliability.

The present study examines the reliability of masked high-frequency bone-conduction threshold measurements in 95 normal-hearing subjects. High-frequency pure-tone air-and bone-conduction thresholds were measured with a dedicated laboratory high-frequency auditory evaluation system using matched, modified Koss Pro/4X Plus earphones, and the Pracitronic KH 70/5 bone vibrator. A 400-Hz wide band masking noise centered at the frequency of the test tone was used to mask the nontest ear. Monaural masked bone-conduction threshold measurements were obtained at the ipsilateral mastoid of the ear with better high-frequency hearing. Two measurements were performed in each session, and each subject participated in two sessions. In several comparisons for test-retest consistency, high-frequency bone-conduction threshold measurements were as repeatable as air-conduction thresholds of identical frequency, or bone-conduction thresholds for frequencies of 4 kHz and less. High-frequency bone-conduction threshold measurement appears to be a sufficiently reliable tool for diagnosis of auditory disorders.