Limits on the use of the MMSE for assessment of capacity to consent for treatment

This study explores to what extent patients scoring in the normal Mini-Mental Status Examination (MMSE) cognitive range have mental incapacity to consent to treatment; and analyzes the relationship between MMSE score and MacArthur Competence Assessment Tool for Treatment (MacCAT-T) scores. Eighty medical inpatients, 40 psychiatric inpatients and 40 healthy controls were assessed. The criterion of expert psychiatrists was the 'gold standard' for capacity. Seven (63.6%) psychiatric patients and two (14.3%) medical patients without capacity performed in a normal MMSE cognitive range (p < 0.001). Statistically significant correlations between MMSE scores and mean MacCAT-T scores were observed in both patient groups (particularly in 'understanding' and 'reasoning'). The MMSE should not be used on its own for assessment of capacity. (c) 2018 Asociacion Universitaria de Zaragoza para el Progreso de la Psiquiatria y la Salud Mental. Published by Elsevier Espana, S.L.U. All rights reserved.