Social and cognitive functioning are often impaired in patients with chronic schizophrenia, and contribute to the illness poor outcome. Relationships between social functioning, psychopathology and cognitive deficits have not been clarified yet.

In the present study the amount of social functioning variance explained by psychopathology and cognitive deficits was investigated in 88 subjects with chronic schizophrenia or schizoaffective disorder. A comprehensive neuropsychological battery was used to assess general cognitive abilities, attention, secondary verbal and visuospatial memory, verbal fluency and executive functions. Psychopathological dimensions were derived from scores on Andreasen's scales for negative and positive symptoms. Social functioning was investigated by the “Assessment of Disability” interview.

Multiple regressions analyses were carried out, in which indices of social functioning were the dependent variables and psychopathological dimensions, neuropsychological indices, antipsychotic treatment type, duration of illness, age and education were the independent variables.

Verbal memory, executive function and sustained attention indices explained together 19.9% of the global disability variance, while negative symptoms explained only 4.4% of the variance. Sustained attention explained 7.2% of the variance of subjects' “availability to start work”, while verbal memory explained 11.1% of the variance of subjects' ability to start and maintain affective relationships.

Our findings suggest that cognitive impairment is an important feature of schizophrenia whose relationships with social functioning is stronger than that of psychopathology.