Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 49 10 2011 10 15 680 687 EN Giti Shams Department of Psychiatry, Roozbeh Hospital, Tehran University of Medical Sciences. Tehran, Iran. Elham Foroughi Department of Psychology, School of Behavioral Science, University of Melbourne, Melbourne Australia. Yaghoob Esmaili Department of Psychology, Rodhen Azad University, Tehran, Iran. Homayoon Amini Department of Psychiatry, Roozbeh Hospital, Tehran University of Medical Sciences. Tehran, Iran. Narges Ebrahimkhani Department of Psychiatry, Roozbeh Hospital, Tehran University of Medical Sciences. Tehran, Iran. 2015 09 28 Recent epidemiological studies show that obsessive-compulsive disorder (OCD) and its comorbidity with psychiatric problems is more prevalent among children and adolescents than was previously believed. The primary aim of the current study is to investigate the point-prevalence rate of obsessive compulsive symptoms in a sample of adolescent high school student in Iran. A two-stage epidemiological study was carried out through a clustered random sampling method. All participants went through a two-stage assessment procedure, in the first screening phase, the Maudsley Obsessive-Compulsive Inventory (MOCI) was administered to 909 randomly selected students (in the age range 14-18 years). Participants were considered possible sub-clinical or clinical OCD cases, if they obtained a score of MOCI≥15. In the second stage, the Symptoms Checklist -90-revised (SCL-90-R) was administered to student who fulfilled the screening criteria. The prevalence of OC symptoms was found to be 11.2 percent for the total sample. The most prevalent comorbid conditions were depression and anxiety with prevalence rates of 91.2 and 78.4 percent respectively. Gender, age, birth-order, parent's education and family income had no statistically significant association with OC symptoms. Further research in this area is warranted in order to establish a set of comprehensive global assessment and measurement tools, which would allow cross-cultural studies in the field of OCD. https://acta.tums.ac.ir/index.php/acta/article/view/3818 https://acta.tums.ac.ir/index.php/acta/article/download/3818/3793