Reference data for DPOAE in healthy newborns

Distortion Product Otoacoustic Emissions (DPOAE) can be used as an alternative to Transient Evoked Otoacoustic Emissions (TEOAE). This study aims to establish normal values for DPOAE in healthy newborns. DPOAE were determined with the Madsen Celesta 503 at 0.5, 1, 2, 4 and 8 kHz with an unequal stimulus level of the primaries (L1 = 65 dB SPL, L2 = 50 dB SPL). DPOAE were present in 92.4% of the ears of the 185 babies tested at 4 days after birth. The 5% quantile and the median of the DPOAE of the right and left ears were calculated for the five frequencies tested. At 4 kHz there was a significant sex effect (mean amplitude of DPOAE was higher in female than in male babies) and at 2 kHz a significant interaction effect was found between sex and side. The calculated reference limits are open to comparison with data obtained using other commercial equipment.