Comparison of transient evoked otoacoustic emissions and distortion product otoacoustic emissions when screening hearing in preschool children in a community setting.

OBJECTIVE: The first purpose of this study was to compare transient evoked otoacoustic emissions (TEOAE) with distortion product otoacoustic emissions (DPOAE) to determine if they resulted in equivalent signal-to-noise ratios (SNRs) when used for hearing screening in a preschool population in a community setting. The second purpose was to determine if the OAE methods would result in equivalent pass/refer rates. The third purpose was to determine the agreement between the pass/refer rates from a tympanometric screening and the pass/refer rates from each OAE method.

METHODS: Thirty-three preschool children ages 4 months to 4 years, 4 months were tested using DPOAE and TEOAE. The frequencies 800-4000Hz were compared. The tympanometric gradient was obtained from a tympanogram done on each ear. A multivariate statistic was used to compare the emission SNR from both methods. A chi(2) statistic was used to compare the pass/refer rates from both methods. The agreement between the pass/refer rates from the OAE screens and from the tympanometric gradient were compared.

RESULTS: TEOAE and DPOAE SNRs were significantly different in the low frequency however, there were no significant differences found in the high frequencies. There were no significant pass/refer differences found between the methods at any frequency. When comparing the agreement between the OAE methods with the tympanometry, both methods produced nearly equivalent agreement with tympanometric gradient. However, the overall correspondence between OAE findings and tympanometry was not perfect.

CONCLUSIONS: Both methods are effective and especially equivalent in the high frequencies and can be recommended for use in a preschool population in the field. Tympanometric gradient disagreed with both OAE screening results about 25% of the time. Finally, our study also found that higher refer rates can be expected when young (<3 years) preschool children are included in the screen.