Tabriz University of Medical Sciences Medical Journal of Tabriz University of Medical Sciences 2783-2031 31 3 2009 09 23 Effect of Cognitive-Behavior Therapy, Exposure and Response Prevention on Obsessive-Compulsive Disorder 71 77 EN Majied Mahmoud Aliloo Mahdi Imani Abbas Bakhshipoor Alireza Farnam Journal Article 2009 12 12 Background and Objectives: Most of the last research indicated that there was not significant difference between cognitive-behavior therapy (CBT) and Exposure and response prevention (ERP) methods to reduce the symptom of Obsessive-Compulsive disorder (OCD). In this study we compared the efficacy of above methods in a group of patients with obsessive-compulsive disorder. Materials and Methods: In this prospective study a group of patients with obsessive-compulsive disorder were randomly assigned in 3 groups: Cognitive-behavior therapy, exposure and response prevention and controls. Patients in 3 groups were matched with respect to the variables such as age, sex, academic and marital status. In this study we used the following tests. Moudsley Obsessive-Compulsive Inventory (MOCI), Beck Depression Inventory-II (BDI-II), Beck Anxiety Inventory (BAI). All patients in each group completed three questionnaires in 3 and (pre test, post test, and after 2 months. The data were analyzed by multivariate analyses of variance-one way (MANOVA-1 way), and post hoc test (T tukey). Results: Finding indicated the treatment effect of cognitive-behavior therapy and exposure and response prevention on obsessive-compulsive disorder were more significant than waiting-list in short-term and long-term (P<0/01). The Inter group difference between cognitive-behavior therapy and exposure and response prevention was not significant. Conclusion: There was not significant difference between ERP and CBT in symptom reduction of OCD.