Clinical subtypes of obsessive-compulsive disorder based on the presence of checking and washing compulsions.

OBJECTIVE We aimed at examining the utility of checking and washing compulsions as markers of valid subtypes of obsessive-compulsive disorder (OCD). METHODS One hundred and six patients with obsessive-compulsive disorder were evaluated with a socio-demographic and clinical questionnaire, the Structured Clinical Interview for DSM-IV, the Yale-Brown Obsessive-Compulsive Scale, the Clinical Global Impression, the Beck Depression Inventory, the Hamilton Rating Scale for Depression, and the Global Assessment of Functioning. These individuals were allocated in one of four subgroups [checkers (OCD-Ch; n = 20), washers (OCD-Wa; n = 13), checkers and washers (OCD-CW; n = 48), and non-checkers and non-washers (OCD non-CW = 25)] on the basis of the presence and the clinical relevance of checking and/or washing compulsive behaviors across their lifetime. Socio-demographic and clinical variables were compared and contrasted between the groups by means of ANOVA followed by post-hoc Least Significant Difference or Dunnett's tests for continuous variables and chi-square tests followed by partitioned chi-square tests for categorical variables. RESULTS OCD-Ch and OCD-Wa did not differ on most demographic and clinical features, the only exception being the number of different types of obsessions, which were significantly higher in the former group. The OCD-CW group was more likely to exhibit an insidious onset of obsessive-compulsive symptoms, to manifest itself as a mixed subtype of obsessive-compulsive disorder and to display obsessions with contamination themes. On the other hand, the OCD non-CW group was more likely to exhibit an acute onset, a shorter duration of illness, obsessions with religious themes, an episodic course, and less severe obsessive-compulsive symptoms. CONCLUSIONS In our sample, the probing of the presence of checking and/or washing compulsions has provided significant empirical support to establish valid subtypes of obsessive-compulsive disorder.