On measuring incapacity.
OBJECTIVE
We review the relevant literature published in the last year on assessing the capacity of mental patients to make decisions in different areas of their lives. We have analyzed the research relating to the development of capacity assessment instruments.


RESULTS
We examine recent studies focusing on the capacity of mental patients with mild to moderate dementia. Also we investigate how brief interventions affect patients' understanding of the implications of being enrolled in a particular research project. A new area of research has emerged in the field trying to elucidate which neuropsychological and clinical factors can help to predict present or future incapacity. There is still debate on the construct validity of capacity since different theoretical approaches can be used.


CONCLUSIONS
Unfortunately there is controversy regarding the utility of neuropsychological and clinical data as predictors of incapacity. It is still necessary, therefore, to use different capacity instruments to ascertain whether patients have sufficient capacity for a specific task or decision.
Calcedo-Barba
Alfredo
A
Department of Psychiatry, Hospital General Universitario Gregorio Marañón, Madrid, Spain. calcedo@med.ucm.es
García-Solano
Fernando
F
Fraguas
David
D
Chapela
Esther
E
D003072:Cognition Disorders / Q000175:diagnosis*; D006801:Humans; D016743:Mental Competency; D009483:Neuropsychological Tests; D011057:Politics