The drawing test: Assessment of coordination abilities and correlation with clinical measurement of spasticity

Objective: To assess the correlation between kinematic measures of movement (Drawing Test) and a clinical measure of spasticity (Ashworth Scale). Design: Correlation study of Drawing Test and the Ashworth Scale scores. Setting: Inpatient rehabilitation center. Participants: Forty-five poststroke hemiplegic subjects with various levels of spasticity (up to Ashworth Scale score of 3) and 8 able-bodied subjects with no sensorimotor deficits in their upper extremities. Interventions: Subjects made self-paced, radial point-to-point movements between the left, and the right corners of a square (200 X 200 mm) on the surface of a drawing tablet. Hand coordinates were recorded from the mouse, which was attached to the hand. Main Outcome Measures: Correlation between (1) Drawing Test scores (time to perform the movement, radial [y] and tangential [x] distances between the end point of the movement and the target endpoint, standard error of the mean calculated as distances between the recorded path and its radial linear fit), and (2) Ashworth Scale scores. Results: Drawing Test scores correlated highly with Ashworth Scale scores in 49 of 53 subjects, based on the multiple linear regression analysis. Conclusions: The Drawing Test, a quantitative metric of movement ability, correlated highly to the Ashworth Scale, a clinical measure of spasticity.