The Influence of Sex, Ear, and Age on Auditory Brainstem Responses Recorded with the NeuroAudio System

Background: Clinical interpretation of the auditory brainstem response (ABR) relies on precise normative data. While our previous work provided evidence of sex-based differences in ABR latencies in a normative sample (N = 73), this larger-scale investigation (N = 244) validates these findings and extends them to other features of the ABR, such as wave amplitude and interaural latency asymmetry. Methods: This retrospective, cross-sectional study collected ABRs from 244 participants aged 3-79 years (134 men, 110 women) with normal hearing. All underwent basic audiological assessment and click-evoked ABR measurement with the NeuroAudio system. Wave latencies, interpeak intervals, and amplitudes were analyzed. Results: Absolute latencies for wave III and wave V, and all interpeak latency intervals, were significantly shorter in women versus men (p ≤ 0.001). No statistically significant sex-based differences were found for wave I and V amplitudes. Statistically significant right versus left ear differences were found for wave V absolute latency and for interpeak intervals I-III and I-V, with the left ear consistently showing prolonged responses compared to the right. No significant interaural differences were identified for waves I and III, or for the III-V interval. Conclusions: This study confirms the significant effect of sex on ABR temporal parameters, but not on wave amplitudes. There were also significant interaural asymmetries. These findings support the use of sex-specific, and potentially ear-specific, normative data to maximize diagnostic accuracy in audiology.