Abstract: Objective To investigate the application of various objective combinative auditory tests in medicolegal experise. Methods 87 hearing impairment subjects (97 ears) involved in injury cases were divided into two groups according to the types of damage: the head trauma group and the ear trauma group. These subjects accepted various combinative auditory tests with pure tone threshold audiometry (PTA), acoustic impedance audiometry, 40 Hertz Auditory Event-related Potential(40 Hz AERP), Auditory brainstem response test (ABR), Auditory mulit-frequency steady-state responses(ASSR), Distortion product otoacoustic emissions(DPOAEs). Results The good relationships in threshold can be found between 40 Hertz Auditory Event-related Potential (40 Hz AERP ) and Auditory steady-state responses(ASSR) of 40Hz in these subjects from 0.5-2 kHz (r=0.862). The positive rate of DPOAEs was higher in head trauma group than in the ear trauma group (P<0.05). The 40 Hz AERP threshold of language frequency overestimate the ASSR threshold in 26 ears by 17dB. Conclusion The components of the combinative auditory tests complete each other in expertise of hearing impairment. The combinative auditory tests make for determination of the location and cause of the injury, and evaluation of hearing threshold.

Key words: hearing injury, head trauma, auditory evoked potentials, forensic audiology