This study is designed to determine the prevalence and clinical severity of obsessive-compulsive symptoms/disorder, aggression and suicidal attempts at the same time in schizophrenic patients with considering the severe anxiety, depression and substance abuse as confounding factors.

In a cross-sectional study, 100 schizophrenic patients who were diagnosed with structured clinical interview were selected with simple sampling. They were evaluated with Yale - Brown Obsessive Compulsive Scale (Y/BOCS), Positive and Negative Syndrome Scale (PANSS), Beck Depression Inventory (BDI), Spilberger State/Trait Anxiety Inventory, Beck Scale for suicide Ideation (BSS) (in the case of recent suicidal attempt), and Overt Aggression Scale (OAS).

Obsessive-compulsive symptoms, obsessive-compulsive disorder and suicidal attempt were seen in 33%, 10% and 12% of patients respectively. Most common form of aggression was against others (55%). Patients did not have important differences from the Severity of schizophrenia, thoughts of suicide and aggression. There were no significant differences between severity of schizophrenia, suicidal ideation and overt aggression in patients with and without obsessive compulsion disorder/symptoms. Severity of overt aggression was related to patients' age and education reversely.

High percentage of aggressive obsessions in this study and lack of significant relationship between severity of aggression and presence of obsessive-compulsion disorder indicates that these patients do not act on these thoughts.