Psychometric analysis of the Yale-Brown Obsessive-Compulsive Scale Second Edition Symptom Checklist.

The Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) was recently revised to address several clinical and conceptual issues. The resultant measure, named the Yale-Brown Obsessive-Compulsive Scale-Second Edition, consists of two primary scales: the Severity Scale and the Symptom Checklist. Although the Severity Scale has been the subject of a comprehensive psychometric analysis, no data have been reported on the psychometric properties of the Y-BOCS-II Symptom Checklist (Y-BOCS-II-SC). Accordingly, in the present study, clinician ratings on the Y-BOCS-II-SC for 130 patients with obsessive-compulsive disorder (OCD) were examined on a number of validity and reliability indices. Partially consistent with past factor analytic studies of the Y-BOCS Symptom Checklist, the Y-BOCS-II-SC yielded four factors representing symmetry/ordering, contamination/washing, hoarding, and sexual/religious/aggression dimensions; checking rituals cross-loaded with other dimensions. Generally, the Y-BOCS-II-SC dimensions were internally consistent and rated stably across raters and over a short interval. The Y-BOCS-II-SC symptom dimensions showed good convergence with self-reported obsessive-compulsive symptoms, and were at best moderately associated with divergent measures (e.g., OCD symptom severity, depressive symptoms, and symptoms of anxiety). Overall, the Y-BOCS-II-SC shows good psychometric properties; we highlight several domains in which the Y-BOCS-II-SC may have clinical and research utility, as well as several areas for future study.