Evaluating voting competence in persons with Alzheimer disease

Voting by persons with dementia raises questions about their decision-making capacity. Methods specifically addressing voting capacity of demented people have been proposed in the US, but never tested elsewhere. We translated and adapted the US Competence Assessment Tool for Voting (CAT-V) to the Italian context, using it before 2006 elections for Prime Minister. Consisting of a brief questionnaire, this tool evaluates the following decision-making abilities: understanding nature and effect of voting, expressing a choice, and reasoning about voting choices. Subjects' performance was examined in relation to dementia severity. Of 38 subjects with Alzheimer's disease (AD) enrolled in the study, only three scored the maximum on all CAT-V items. MMSE and CAT-V scores correlated only moderately (r = 0.59; P < 0.0001) with one another, reflecting the variability of subjects' performance at any disease stage. Most participants (90%), although performing poorly on understanding and reasoning items, scored the maximum on the choice measure. Our results imply that voting capacity in AD is only roughly predicted by MMSE scores and may more accurately be measured by a structured questionnaire, such as the CAT-V. Among the decision-making abilities evaluated by the CAT-V, expressing a choice was by far the least affected by the dementing process.