Abstract: Objective To provide new objective technology in evaluating hearing loss for forensic expert by comparing the thresholds acquired with auditory steady-state responses(ASSR) and pure tone audiometry(PTA)in our laboratory.Methods Twenty-seven subjects with normal hearing(54 ears,18-28years)were tested with PTA and ASSR at 500,1 000,2 000 and 4 000 Hz.Paired t-test analysis was performed on threshold of ASSR and PTA at difference frequency(500,1 000,2 000 and 4 000 Hz).Results At each frequency(500,1 000,2 000 and 4 000 Hz),the thresholds acquired with ASSR were higher than those acquired with PTA(P<0.05).The mean difference of each frequency were(22.04±5.79) dB(500 Hz),(11.02±5.44) dB(1 000Hz),(12.59±5.89) dB(2 000 Hz) and(17.78±7.25) dB(4 000 Hz).The mean difference between the system automatically adjusted threshold of ASSR and PTA were(-3.96±5.79) dB at 500 Hz,(0.02±5.44) dB at 1 000 Hz,(-0.41±5.89) dB at 2 000 Hz,and(-1.25±7.25) dB at 4 000 Hz.Conclusion At each frequency(500,1 000,2 000 and 4 000 Hz),the thresholds acquired with ASSR were higher than those acquired with PTA.The mean difference is 16.9 dB.As an objective and mature method,ASSR could be used in evaluation of hearing-loss degree for forensic expert.But adjusted threshold value should be established when ASSR is used to estimate hearing threshold in each laboratory.

Key words: forensic medicine, audiometry, pure-tone, auditory threshold, auditory steady state responses