RESUMO
To investigate the association between competence to give informed consent to treatment, specific symptomology and diagnostic category, 110 inpatients diagnosed with DSM-IV acute schizophrenia (n = 64), schizoaffective disorder (n = 25) and bipolar affective disorder (n = 21) were interviewed using the MacArthur Competence Assessment Tool for Treatment (MacCAT-T) and the Positive and Negative Syndrome Scale (PANSS). Results indicated no significant difference in competence between the three disorders. Elevated positive, cognitive and excitement PANSS factor scores had lower MacCAT-T scores. Further analyses indicated symptoms that impair cognition; particularly, conceptual disorganisation and poor attention were most consistently related to poor performance on competence tests.