Effectiveness of Cognitive Behavioral Therapy based on Exposure and Response Prevention on Patients with Contamination Obsessive-Compulsive disorder and Scrupulosity

Introduction: The aim of the present study was to compare the effectiveness of cognitive behavior therapy based on exposure and response prevention on the patients with contamination obsessive-compulsive disorder (OCD) and scrupulosity. Methods: The method was semi-experimental pretest-posttest design by control group. Sixty OCD participants who were suffering from scrupulosity and contamination OCD were diagnosed by means of diagnostic interviewing, Yale-Brown Obsessive-Compulsive Scale and Penn inventory of scrupulosity. They were selected through convenience sampling method and were assigned in two experimental groups and one control group (each group 20). The cognitive behavioral therapy based on exposure and response prevention was performed on the subjects in nine individual sessions for 45 minutes for each experimental group. The data were analyzed using SPSS Inc., Chicago, IL; Version 16 by the multivariate analysis of covariance. Results: The results of multivariate analysis of covariance and Bonferroni post hoc tests showed that cognitive behavioral therapy based on exposure and response prevention were effective in decreasing OCD in the experimental groups compared to the control group (0.001≥ P). Bonferroni post hoc test showed that there was a significant difference between the scrupulosity group and the contamination group and control group on the obsession variable (0.05 < P). There was no significant difference between the contamination group and the scrupulosity group on the compulsion variable (0.15 < p). Conclusion: The findings suggest that cognitive behavioral therapy based on exposure and response prevention could help alleviate symptoms of obsessive-compulsive disorder in both religious and contamination OCD.