- Abstract The obsessive–compulsive spectrum disorder (OCSD) theory postulates that a wide range of disorders is closely related to OCD. Current cognitive models ascertain that certain beliefs leading to misinterpretation of the significance of intrusions are important in the etiology and maintenance of OCD. This study examined whether pathological gambling, a disorder belonging to the OC spectrum, is characterized by similar dysfunctional cognitions as OCD. Dysfunctional beliefs of OCD patients were compared to those of patients with pathological gambling, panic disorder and normal controls. These beliefs were measured by the Obsessive–compulsive Beliefs Questionnaire-87 (OBQ-87), which was developed by a group of leading OCD researchers [Behav. Res. Ther. 35 (1997) 667]. It was hypothesized that according to the OCSD theory, pathological gamblers would exhibit similar cognitions to OCD patients, as well as increased levels of OCD symptoms. Analysis showed that OCD patients exhibited higher OBQ-87 scores than both panic patients and normal controls, but equal to pathological gambling patients. Pathological gamblers exhibited, however, no increase in OCD symptoms. These mixed results do not seem to support the OC spectrum theory for pathological gambling, moreover being contradictory to contemporary cognitive OCD models.