DISTORTION-PRODUCT OTOACOUSTIC EMISSION TEST OF SENSORINEURAL HEARING-LOSS - PERFORMANCE REGARDING SENSITIVITY, SPECIFICITY AND RECEIVER OPERATING CHARACTERISTICS

The performance of distortion product otoacoustic emissions (DPOEs) as a frequency-specific test of sensorineural hearing loss was evaluated in 142 ears of human adults with normal middle-ear function. The DPOE was measured with the stimulus levels of the two tones equal to 65 dB SPL (re 20 mu Pa) and the ratio between the two frequencies 1.2. In t he DPOE test, the cochlear function of an ear at a test frequency was predicted to be normal or abnormal depending upon whether the DPOE lev el with the geometric mean of the two stimulus frequencies at the test frequency was greater or less than a criterion. The DPOE test outcome s were evaluated against the pure-tone hearing threshold as the standa rd. We found the sensitivity, specificity and predictive efficiency of the test to be 85-89% at 6000 and 4000 Hz, 82-83% at 2000 Hz and 78-7 9% at 1000 Hz, respectively. The performance was also evaluated using decision theory in terms of the area under the receiver operating char acteristics. The latter was found to range from 0.90 (for 1000 Hz) to 0.94 (for 6000 Hz). These findings support the conclusion that the DPO Es can form a useful frequency-specific objective rest of cochlear fun ction.