Myth of the pure obsessional type in obsessive--compulsive disorder

Background: Several studies have identified discrete symptom dimensions in obsessive–compulsive disorder (OCD), derived from factor analyses of the individual items or symptom categories of the Yale–Brown Obsessive–Compulsive Scale Symptom Checklist (YBOCS‐SC). This study aims to extend previous work on the relationship between obsessions and compulsions by specifically including mental compulsions and reassurance‐seeking. Because these compulsions have traditionally been omitted from prior factor analytic studies, their association to what have been called “pure obsessions” may have been overlooked. Method: Participants ( N =201) were recruited from two multi‐site randomized clinical treatment trials for OCD. The YBOCS‐SC was used to assess OCD symptoms, as it includes a comprehensive list of obsessions and compulsions, arranged by content category. Each category was given a score based on whether symptoms were present and if the symptom was a primary target of clinical concern, and a factor analysis was conducted. Mental compulsions and reassurance‐seeking were considered separate categories for the analysis. Results: Using an orthogonal geomin rotation of 16 YBOCS‐SC categories/items, we found a five‐factor solution that explained 67% of the total variance. Inspection of items that composed each factor suggests five familiar constructs, with mental compulsions and reassurance‐seeking included with sexual, aggressive, and religious obsessions (unacceptable/taboo thoughts). Conclusions: This study suggests that the concept of the “pure obsessional” (e.g., patients with unacceptable/taboo thoughts yet no compulsions) may be a misnomer, as these obsessions were factorially associated with mental compulsions and reassurance‐seeking in these samples. These findings may have implications for DSM‐5 diagnostic criteria. Depression and Anxiety, 2011. © 2011 Wiley‐Liss, Inc.