Objective: The aim of this study was to examine the effect of the number of averaged responses on the measurement of transiently evoked otoacoustic emissions (TEOAEs).
Methods: The study was performed on the background of a universal newborn hearing screening program implemented in Iaso Maternity Hospital. Two groups of full-term newborns with normal otoacoustic emissions were studied. The first group included 58 newborns (115) ears, in which 260 low-noise samples, provided by the default setting of the equipment used (ILO88), were presented. The second group included 58 newborns (113) ears, in which 20-50 averaged responses were presented, until the "pass" criteria would be met. Statistical comparison between the following parameters recorded during TEOAE measurement was performed: Overall response, signal-to-noise ratios, reproducibility (whole and partial), stimulus intensity, stimulus stability, input noise, noise rejection level and duration of testing.
Results: Statistically significant differences were found in most of these parameters, except for overall response, stimulus intensity and noise rejection level.
Conclusions: Although a smaller number of clicks is usually sufficient to obtain a "pass" in newborn hearing screening programs, the quality of recording of TEOAEs is significantly improved by increasing the number of averaged low-noise responses.