Do dysfunctional beliefs play a role in all types of obsessive–compulsive disorder?

Some but not all models of obsessive–compulsive disorder (OCD) emphasize the role of dysfunctional beliefs in the etiology and maintenance of this disorder. Clinical observations suggest that some OCD patients have prominent dysfunctional beliefs associated with their obsessions and compulsions, while other patients do not show this pattern. It is possible that dysfunctional beliefs play a role in only a subgroup of cases of OCD and, by extension, that different models might apply to different subtypes of the disorder. To examine this issue, patients with OCD (N = 244) completed measures of dysfunctional OC-related beliefs, along with measures of OC symptoms and demographics. These measures were also completed by three comparison groups; anxious (N = 103), student (N = 284), and community (N = 86) controls. Cluster analysis revealed two OCD clusters: low versus high scores on beliefs (OC-low, OC-high). Belief scores for OC-low were in the range of scores for the comparison groups, which were all significantly lower than those of OC-high. Thus, a cluster of OCD patients was identified who did not have elevated scores on measures of dysfunctional beliefs. OC-low and OC-high did not differ on some OC measures (contamination, checking, grooming), but OC-high had higher scores on measures of harming obsessions. These results are consistent with the view that dysfunctional beliefs may play a role in only some types of OCD.