Comparative Study on Method of Threshold Estimation: Distortion Product Threshold Test versus Pure Tone Threshold Test

Abstract Introduction Distortion product otoacoustic emissions (DPOAEs) can be helpful in estimating the hearing thresholds by extrapolating the DPOAE input/output function with the help of scissor paradigm, and thus the following study aims at assessing its reliability by comparing DPOAE thresholds with those obtained by behavioral responses at pure tones on various frequencies. Materials and Methods Fifty participants having normal hearing sensitivity were included in the study. Pure tone (PT) audiometry was carried out on all participants to determine PT thresholds in both ears. DPOAE threshold test was administered and thresholds at 1, 2, 4, and 8 kHz were compared accordingly. Results The result indicated significant difference between the two methods of threshold estimation where the mean difference was found to be 3 decibel (dB) and 4 dB for left and right ears, respectively. Shapiro-Wilk test revealed normal distribution ( p > 0.05) of the data. Hence, parametric paired t -test was performed, which revealed significant difference between PT and distortion product thresholds. Conclusion Study concludes as having good clinical applicability in assessing neonates and infants.