A correlational study between signature, writing abilities and decision-making capacity among people with initial cognitive impairment

Background Some clinical conditions, including dementia, compromise cognitive functions involved in decision-making processes, with repercussions on the ability to subscribe a will. Because of the increasing number of aged people with cognitive impairment there is an acute and growing need for decision-making capacity evidence-based assessment. Aims Our study investigates the relationship between writing abilities and cognitive integrity to see if it is possible to make inferences on decision-making capacity through handwriting analysis. We also investigated the relationship between signature ability and cognitive integrity. Methods Thirty-six participants with diagnosis of MCI and 38 participants with diagnosis of initial dementia were recruited. For each subject we collected two samples of signature-an actual and a previous one-and an extract of spontaneous writing. Furthermore, we administered a neuropsychological battery to investigate cognitive functions involved in decision-making. Results We found significant correlations between spontaneous writing indexes and neuropsychological test results. Nonetheless, the index of signature deterioration does not correlate with the level of cognitive decline. Discussion Our results suggest that a careful analysis of spontaneous writing can be useful to make inferences on decision-making capacity, whereas great caution should be taken in attributing validity to handwritten signature of subjects with MCI or dementia. Conclusions The analysis of spontaneous writing can be a reliable aid in cases of retrospective evaluation of cognitive integrity. On the other side, the ability to sign is not an index of cognitive integrity.