Tehran University of Medical Sciences Auditory and Vestibular Research 2423-480X 22 3 2017 07 31 89 101 Sara Sardari Department of Audiology, School of Rehabilitation, Tehran University of Medical Sciences, Iran Seyed Jalal Sameni Department of Audiology, School of Rehabilitation, Tehran University of Medical Sciences, Iran Zahra Jafari Department of Basic Sciences in Rehabilitation, School of Rehabilitation, Tehran University of Medical Sciences, Iran Hamid Haghani Department of Statistics and Mathematics, School of Management, Tehran University of Medical Sciences, Iran Saeid Salek Pejvak Ava Corporation, Tehran, Iran 2017 05 29 Background and Aim: Behavioral audiometry is the best method of hearing evaluation. Hearing thresholds are estimated with auditory evoked responses in patients who are not able to cooperate in behavioral audiometry. Because rehabilitative decisions are based on behavioral thresholds, it is essential to determine the amount of difference between behavioral and evoked response thresholds. The purpose of this study was to evaluate the difference between functional and auditory steady-state response (ASSR) gains. Methods: Twenty six moderate to severe hearing impaired adolescents and adults (age range: 14 to 55 years) participated in this interventional-comparative study. Audiometery and ASSR testing was performed (without hearing aid and then with hearing aid). Finally, functional gain with ASSR gain, and behavioral thresholds with ASSR thresholds were compared using paired t-test and correlation statistical methods. All tests were performed in the sound field. Results: The mean difference was 6.19 dB between unaided behavioral and ASSR thresholds, 4.33 dB between aided thresholds, and 2.43 dB between functional and ASSR gains. There was no significant difference between functional and ASSR gains (p>0.05). Conclusion: The difference between functional and ASSR gains is less than the difference between behavioral and ASSR thresholds and it has less variability between different frequencies. So, it may be better to use ASSR gain instead of ASSR thresholds in hearing aid fitting in difficult-to-test population. https://avr.tums.ac.ir/index.php/avr/article/view/300