Computerized kinematic analysis of the clock drawing task in elderly people with mild Major Depressive Disorder: an exploratory study

Abstract

Developments in data collection technology enable evaluation of kinematic characteristics of the drawing process. We examined the clock drawing task in elderly patients with mild Major Depressive Disorder (MDD), assessed the relative importance of kinematic measures that differentiate the groups and analyzed associations between computerized measures, and the cognitive and depression status of the study groups. The participants comprised 20 elderly people with mild MDD and 20 matched controls. Both groups performed a clock drawing task using a computerized system. Kinematic measures included: number of segments drawn, performance time, pressure implemented towards the drawing surface, and pen azimuth. Three representative spatial characteristics were analyzed per segments drawn on the paper: height, width and length. The clock drawing tasks were blindly scored with Freedman's method. Cognitive state was quantified using the Mini-mental State Examination (MMSE) and depression with the Geriatric Depression Scale (GDS). Freedman's method found no between-group differences. Pressure and azimuth measures and spatial measures of segments height, width and length were significantly lower in the mild MDD group, while the number of paper segments and performance time did not differ. The azimuth measure correlated with the GDS score, and pressure with the MMSE and the GDS scores. Spatial measures did not correlate with either the MMSE or GDS. Pressure, segment width and length, azimuth and segment height allowed correct classification of 81.1% of the participants. A computerized system focusing on the clock drawing task might be sensitive to altered performance among elderly people with mild MDD.