AU - Gorji, R. AU - Hassanzadeh, S. AU - Ghasemzadeh, S. AU - GholamAli Lavasani, M. TI - Sensitivity, Specificity, and Accuracy of the Persian Version of 3rd Edition of the Gilliam Autism Rating Scale (GARS- 3): A Descriptive Study PT - JOURNAL ARTICLE TA - RUMS_JOURNAL JN - RUMS_JOURNAL VO - 20 VI - 9 IP - 9 4099 - http://journal.rums.ac.ir/article-1-6113-en.html 4100 - http://journal.rums.ac.ir/article-1-6113-en.pdf SO - RUMS_JOURNAL 9 ABĀ  - Background and Objectives: In recent years, an increase in the prevalence of autism spectrum disorder (ASD) has made it to be one of the significant neurodevelopmental disorders, and well-timed diagnosis for effective intervention has always been emphasized. Using the tools with desirable psychometric features for the considered population is one of the diagnostic ways of the disorder. The goal of the study was to specify sensitivity, specificity, and accuracy of 3rd version of GARS-3 edition (Gilliam autism rating scale- 3) in Persian. Materials and Methods: This descriptive research is of authentication type. The statistical sample was selected from four provinces in 2019- 2020 and included 3- 22 year-old people; out of which 117 were autistic, 55 deaf, 94 mental retarded, and 52 normal. The data was collected from the sample group and GARS (2013) questionnaire then was analyzed by descriptive indexes. Results: The results indicated that for both 4 and 6-point scales in accuracy index, the maximum amount for the autistic and normal groups was 0.93, and the minimum amount for the autistic and mental retarded ones was 0.76. In specificity index, the maximum amount for the autistic and normal groups was 0.90, and the minimum amount for the autistic and mental retarded ones was 0.52, and finally for sensitivity index the amount was 0.95. Conclusion: With regard to the achieved results of 3 significant psychometric scopes, using this type of screening tool to diagnose ASD in Iranian kids is advised. Although using other psychometric findings is also emphasized. Key words: Autism spectrum disorder, Psychometric indexes, GARS- 3 Funding: This study did not have any funds. Conflict of interest: None declared. Ethical approval: The Ethics Committee of Islamic Azad University, Science and Research Branch, approved the study (IR.IAU.SRB.REC.1398.153). How to cite this article: Gorji R, Hassanzadeh S, Ghasemzadeh S, GholamAli Lavasani M. Sensitivity, Specificity, and Accuracy of the Persian Version of 3rd Edition of the Gilliam Autism Rating Scale (GARS-3): A Descriptive Study. J Rafsanjan Univ Med Sci 2021; 20 (9): 989-1002. [Farsi] CP - IRAN IN - Department of Psychology LG - eng PB - RUMS_JOURNAL PG - 989 PT - Research YR - 2021