Div. of Otolaryngol., Univ. of Connecticut Health Ctr., 263 Farmington Ave., Farmington, CT 06030-1110
Click-evoked otoacoustic emissions (CEOEs) were collected from 167 ears of 106 normal-hearing children using the ILO88 system with the stimuli presented at 80(plus or minus)2 dB pe SPL. Subjects were divided into five age groups: 13--24 months (24 ears), 25--36 months (49 ears), 37--48 months (31 ears), 49--60 months (34 ears), and 61--72 months (29 ears). All subjects had normal middle ear function and their audiological data were within normal limits. Mean overall CEOE level was calculated for each age group. None was statistically different from any other. However, the data of the 167 ears showed small but statistically significant decrease in CEOE level as age increased. Combined data of 61 subjects, who were tested in both ears, revealed statistically significant correlation between the CEOE levels from both ears of the same individual and also indicated that the right ears exhibited significantly higher CEOEs than the left ears. The CEOEs recorded from each individual ear were analyzed by calculating rms levels within five half-octave bands in the 0.8- to 4.8-kHz region. The values corresponding to the 10th percentiles were calculated for the five half-octave bands based on the rms CEOE data of the 167 ears. The 10th percentiles were used to define pass/fail criteria of the CEOE test for hearing-impaired children's ears.