Tehran University of Medical Sciences Auditory and Vestibular Research 2423-480X 31 3 2022 07 05 175 179 Mohammadsaleh Moosapour Bardsiri Department of Audiology, School of Rehabilitation, Shahid Beheshti University of Medical Sciences, Tehran, Iran Mohammad Ebrahim Mahdavi Department of Audiology, School of Rehabilitation, Shahid Beheshti University of Medical Sciences, Tehran, Iran 2021 09 18 2021 11 13 Background and Aim: The psychometric function characteristics (e.g. threshold and slope) of the time-compressed words have not been investigated in previous studies to compile psychometrically homogeneous word lists. Therefore, this study aimed to investigate psychometric function characteristics of monosyllabic time-compressed Persian words to develop psychometrically equivalent time-compressed word lists. Methods: Two hundred most common monosyllabic words in Persian language were timecompressed at a rate of 40%-85% and presented to 21 participants with normal hearing at a fixed intensity level. The threshold and slope of the psychometric function for all words were determined using the logistic regression. The compression ratio (CR) for 5%-95% correct recognition was predicted based on the psychometric function fitted to the measured correct recognition score. Results: Mean CR 50% of the words was in a range of 53%-78%. The mean CR 50% and slope were not significantly different between consonant-vowel-consonant and consonantvowel-consonant-consonant words. The predicted CR for 5%-95% correct recognition varied from 61.5% to 88.4%. The final result was two 50-word lists of monosyllabic words with the same mean threshold and slope. Conclusion: Persian time-compressed monosyllabic words have different CR 50% and slope that may interact with their intelligibility. https://avr.tums.ac.ir/index.php/avr/article/view/997