Factor structure of the Yale–Brown Obsessive–Compulsive Scale (Y-BOCS) in a large sample of patients with schizophrenia or related disorders and comorbid obsessive–compulsive symptoms

Abstract

a b s t r a c t a r t i c l e i n f oIn the past decade there has been an increasing interest in the levels of obsessive-compulsive symptoms (OCS) found in patients with schizophrenia or related disorders. The widely acknowledged gold standard measure of the severity of OCS is the content-free version of the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) (Goodman et al., 1989a,b). However, factor analytic research in patients with obsessive-compulsive disorder (OCD) provided varied results. So far no study has been conducted on the factor structure of the Y-BOCS in patients with schizophrenia. The present study addresses this issue. We administered the Y-BOCS in a sample of 217 patients with schizophrenia or related disorders and comorbid OCS who participated in a multicentre cohort study. We used principal component analysis (PCA) to explore the underlying factor structure. A two-factor solution consistent with the originally proposed scoring structure of the Y-BOCS provided the optimal fit. We also found some support for a three-factor solution consistent with earlier findings by Kim et al. and Moritz et al. (Kim et al., 1994;Moritz et al., 2002). The produced factors showed good reliability and strong correlations with the Y-BOCS Total score. However, the resistance to compulsion item failed to demonstrate adequate correlation to the Total score, a finding consistent with earlier findings in several studies with patients with OCD.

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“…This is in agreement with a number of factor analytic studies indicating that obsessions and compulsions are only weakly correlated and that the Y-BOCS is best represented by two (obsessions versus compulsions; Boyette, Swets, Meijer, Wouters, & Authors, 2010;McKay, Danyko, Neziroglu, & Yaryura-Tobias, 1995) or three (obsessions, compulsions and resistance; Kim, Dysken, Pheley, & Hoover, 1994;Moritz et al, 2002) rather independent factors. However, we need to acknowledge that there are some exceptions, with studies reporting somewhat higher correlations between obsessions and compulsions (e.g., Gönner & Kupfer, in preparation;McKay et al, 1995).…”

‘Impulsive compulsivity’ in obsessive-compulsive disorder: A phenotypic marker of patients with poor clinical outcome

“…This concept can be investigated in OCD by focussing on the resistance and control dimensions of the Yale-Brown Obsessive Compulsive Scale (Y-BOCS). Curiously, previous studies have suggested that resistance to symptoms, together with control over symptoms (Deacon and Abramowitz, 2005), decreases the internal consistency of the Y-BOCS (Woody et al, 1995) and loads on a third factor, independently from obsessive and compulsive constructs (Boyette et al, 2011;Kim et al, 1994). Importantly, Deacon and Abramowitz (2005) demonstrated a clear double dissociation between two factors in the Y-BOCS e 'Severity' and 'Resistance/Control'.…”

Relevance of Five-Factor Model personality traits for obsessive–compulsive symptoms in patients with psychotic disorders and their un-affected siblings

“…This instrument allows the rating of compulsions and obsessions separately on a five-point Likert-scale (0-4) yielding subtotal scores ranging from 0 to 20. The YBOCS is able to reliably assess the severity of OCS in schizophrenia (de Haan et al, 2006;Boyette et al, 2011).…”