This study aimed to assess the decision-making capacity for treatment of patients hospitalized in an internal medicine ward of a General Hospital in Greece, and to examine the views of treating physicians regarding patients' capacity. All consecutive admissions to an internal medicine ward within a month were evaluated. A total of 134 patients were approached and 78 patients were interviewed with the MacArthur Competence Assessment Tool for Treatment (MacCAT-T) and the Mini Mental State Examination (MMSE) questionnaire. Sixty-eight out of 134 patients (50.7%) were incompetent to decide upon their treatment. The majority of them (n=56, 41.8%) were obviously incapable because they were unconscious, or had such marked impairment that they could not give their own names, and the rest (n=12, 8.9%) were rated as incompetent according to their performance in the MacCAT-T. Neurological disorders, old age and altered cognitive function according to MMSE were negatively correlated with decision making capacity. Physicians sometimes failed to recognize patients' incapacity. Rates of decision-making incapacity for treatment in medical inpatients are high, and incapacity may go unrecognized by treating physicians. Combined patient evaluation with the use of the MacCAT-T and MMSE, could be useful for the determination of incapable patients.
Keywords: Decision-making capacity for treatment; MacCAT-T; informed consent; medical patients..