Further psychometric properties of the Yale–Brown Obsessive Compulsive Scale — Second Edition

Abstract

The Yale–Brown Obsessive Compulsive Scale (Y-BOCS) is a widely used clinician-rated measure for assessing obsessive–compulsive symptoms. Although numerous studies have supported its reliability and validity, improved phenomenological understanding of obsessive–compulsive disorder (OCD) suggests the need for modifications to item content, structure, and scoring. Consequently, the Yale–Brown Obsessive Compulsive Scale — Second Edition (Y-BOCS-II) was developed. While the Y-BOCS-II shows initial promise, minimal data exist in examining the psychometric properties of the Y-BOCS-II English version. In response, the Y-BOCS-II was administered to 61 adult patients with a principal diagnosis of obsessive–compulsive disorder. The internal consistency for the scores on the Obsession Severity (α=.83), Compulsion Severity (α=.75), and Total Severity (α=.86) scales were acceptable to good. The inter-rater reliability for the severity scale scores was excellent (ICC=.97–99) and the test–retest reliability was acceptable (r=.64–81). Strong convergent validity was observed between the Y-BOCS-II Total Severity scale and other measures of obsessive–compulsive symptom severity and related impairment. Good divergent validity was supported by non-significant correlations between the Total Severity score and measures of anxiety and impulsiveness, though a moderate correlation was observed with depressive symptoms. Collectively, the Y-BOCS-II generally possesses sound psychometric properties and appears to be a viable alternative to the original Y-BOCS.