An Evaluation of the Wolf Motor Function Test in Motor Trials Early After Stroke

Abstract Edwards DF, Lang CE, Wagner JM, Birkenmeier R, Dromerick AW. An evaluation of the Wolf Motor Function Test in motor trials early after stroke. Objective To examine the internal consistency, validity, responsiveness, and advantages of the Wolf Motor Function Test (WMFT) and compare these results to the Action Research Arm Test (ARAT) in participants with mild to moderate hemiparesis within the first few months after stroke. Design Data were collected as part of the Very Early Constraint-Induced Therapy for Recovery from Stroke (VECTORS) trial, an acute, single-blind randomized controlled trial of constraint-induced movement therapy. Subjects were studied at baseline (day 0), after treatment (day 14), and after 90 days (day 90) poststroke. Setting Inpatient rehabilitation hospital; follow-up 3 months poststroke. Participants Hemiparetic subjects (N=51) enrolled in the VECTORS trial. Intervention None. Main Outcome Measures At each time point, subjects were tested on (1) the WMFT and ARAT, (2) clinical measures of sensorimotor impairments, (3) reach and grasp movements performed in the kinematics laboratory, and (4) clinical measures of disability. Blinded raters performed all evaluations. Analyses at each time point included calculating effect size as indicators of responsiveness, and correlation analyses to examine relationships between WMFT scores and other measures. Results The WMFT is internally consistent, valid, and responsive in the early stages of stroke recovery. Sensorimotor and kinematic measures of reach and grasp support the construct validity of the WMFT. Conclusions In an acute stroke population, the WMFT has acceptable reliability, validity, and responsiveness to change over time. However, when compared with the ARAT, the higher training and testing burdens may not be offset by the relatively small psychometric advantages.