Objective: Although several self-report versions of the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) have been developed and used widely, few psychometric studies have established the construct validity of this measure. Therefore, we developed Korean self-report version of the Y-BOCS and evaluated its factor structure, reliability, and validity.

Methods: A non-clinical student sample (n=206) and a clinical OCD sample (n=199) completed the Korean self-report version and other measures of obsessive-compulsive disorder (OCD), depression, and anxiety.

Results: Consistent with the originally proposed structure, confirmatory factor analyses supported a factor structure comprised of Obsessions and Compulsions factors in the Korean self-report version. Two subscale scores and the total score of the Korean self-report version showed good internal consistency and convergent validity, but relatively poor discriminant validity. Applying a cutoff score of 16, 84% of OCD patients and 93% of the non-clinical sample were classified correctly.

Conclusion: Korean self-report version of the Y-BOCS is a psychometrically sound and valid measure for assessing OCD symptoms as compared with the clinician-administered version. The originally proposed division of OCD severity into obsessions and compulsions appears accurate in the Korean self-report version. The cutoff score for the Korean self-report version needs adjustment based on further researches.