Tehran University of Medical Sciences Journal of Modern Rehabilitation 2538-385X 12 4 2019 09 28 217 224 Hamidreza Farmani Department of Speech Therapy, School of Rehabilitation, Tehran University of Medical Sciences, Tehran, Iran. Fatemeh Sayyahi Department of Speech Therapy, School of Rehabilitation, Tehran University of Medical Sciences, Tehran, Iran. Zahra Soleymani Department of Speech Therapy, School of Rehabilitation, Tehran University of Medical Sciences, Tehran, Iran. Fariba Zadeh Labbaf Department of Speech Therapy, School of Rehabilitation, Tehran University of Medical Sciences, Tehran, Iran. Elnaz Talebi Department of Speech Therapy, School of Rehabilitation, Tehran University of Medical Sciences, Tehran, Iran. Zahra Shourvazi Department of Speech Therapy, School of Rehabilitation, Tehran University of Medical Sciences, Tehran, Iran. 2019 09 28 Introduction: The Phonological Working Memory (PWM) plays an essential role in many cognitive functions, such as language acquisition. Impaired PWM can result in learning disability. Therefore, the existence of a standard test for the assessment of this ability, especially in children, is vital. Evidence suggests that the Non-Word Repetition (NWR) task is a good representative of PWM competence. This study aimed to normalize the NWR test for Farsi-speaking children. Also, we aimed at assessing the external reliability of this test. Materials and Methods: The NWR test, including main and parallel tests, was performed on 455 typically-developed children in five age groups ranging from four to nine years old. We attempted to have an almost equal number of participants in different socio-economic status groups and sexes. Results: We found a remarkable relationship between the main and parallel test results (P≤0.001). There was a direct relationship between age and NWR performance in the main (P≤0.001) and the parallel (P≤0.001) tests. Also, boys obtained better total scores in the main (P=0.002) and the parallel (P≤0.001) tests. Conclusion: The test has high external reliability. The results showed non-word repetition ability increased with age. The reported standard scores and normative data can be used for screening and assessing PWM among children. https://jmr.tums.ac.ir/index.php/jmr/article/view/214 https://jmr.tums.ac.ir/index.php/jmr/article/download/214/138