Examining the factor structure of the self-report Yale-Brown Obsessive Compulsive Scale Symptom Checklist.

Obsessive-compulsive symptom dimensions are important in studies about the pathogenesis and treatment of obsessive-compulsive disorder. More than 30 factor analytic studies using the Yale-Brown Obsessive Compulsive Scale Symptom Checklist (Y-BOCS-SC) interview version have been published. However, a drawback of the Y-BOCS-SC interview is that it is time-consuming for the clinician. Baer's self-report version of the Y-BOCS-SC could be a less time-consuming alternative. The purpose of this study was to examine the factor structure of Baer's self-report Y-BOCS-SC. In a sample of 286 patients, we performed two factor analyses, one using categories and one using items of the Y-BOCS-SC. Using category-level data, we identified four factors; when using items we identified six factors. Symptom dimensions for contamination/cleaning, symmetry/repeating/counting/ordering and hoarding were found in both analyses. The impulsive aggression, pathological doubt, sexual, religious somatic and checking categories formed one factor in the analysis using category-level data and divided into three factors using item-level data. These factors correspond with studies using the interview version and support our hypothesis that the self-report version of the Y-BOCS-SC could be an alternative for the interview version.