Symptom structure in Japanese patients with obsessive-compulsive disorder

Objective: Obsessive-compulsive disorder (OCD) comprises a number of specific symptom dimensions. The authors factor analyzed data on the Yale-Brown Obsessive Compulsive Scale symptom checklist in a large group of Japanese OCD patients to examine whether symptom dimensions were stable across cultures. Method: A principal components analysis of Yale-Brown Obsessive Compulsive Scale major symptom categories was performed on Japanese OCD patients (N=343). The association between symptom dimensions and clinical variables, including 1-year outcome after combination treatment, was also examined using Pearson correlations. Results: Four factors explaining 57.7% of the variance were identified: 1) contamination/washing, 2) hoarding, 3) symmetry/repeating and ordering, and 4) aggressive/checking symptoms. The symmetry dimension was associated with early age at onset, and both the symmetry and hoarding dimensions were associated with decreased functioning and treatment resistance. Conclusions: The findings in this study support transcultural stability in the symptom structure of OCD, which is consistent with the hypothesis that OCD is mediated by universal psychobiological mechanisms.