Reliability and validity of the Japanese version of the Obsessive-Compulsive Inventory-Revised (OCI-R)

The objective of the present study was to investigate the factor structure, and the reliability and validity of the Japanese version of the Obsessive-Compulsive Inventory-Revised (OCI-R). The participants included 214 university students enrolled at two universities in a metropolitan area. They completed the OCI-R and other related scales, and of these, 38 students answered the OCI-R again two weeks later. Based on a factor analysis, the six-factor structure, the same as the original version, was confirmed. For reliability, internal consistency and test-retest reliability were evaluated and both internal consistency and test-retest reliability were confirmed. For convergent validity, we calculated the correlation coefficient using the Japanese version of the Maudsley Obsessional-Compulsive Inventory, which measures obsessive-compulsive symptoms. For concurrent validity, we calculated the correlation coefficient using the Patient Health Questionnaire-9, which measures depressive symptoms; and the Generalized Anxiety Disorder-7, which measures anxiety symptoms. Overall, the factor structure, the reliability, and the validity of the Japanese version of the OCI-R were all confirmed in this study. In the future, we will investigate whether the same results can be obtained in clinical groups.