Assessing Wolf Motor Function Test as Outcome Measure for Research in Patients After Stroke

TLDR

The Wolf Motor Function Test (WMFT) is a new time‑based assessment that evaluates upper‑extremity performance and provides joint‑specific and total limb movement insights. This study examined selected psychometric properties of the WMFT in a chronic stroke population. Nineteen chronic stroke survivors with intact cognition and sitting balance were age‑ and sex‑matched to 19 unimpaired controls; each performed the WMFT and the upper‑extremity Fugl‑Meyer Assessment on two occasions 12–16 days apart, with independent scoring by two random raters. The WMFT demonstrated excellent inter‑rater reliability (P < 0.0001), discriminated between impaired and unimpaired limbs, correlated with the FMA for the more affected side (P < 0.02), and its construct and criterion validity were confirmed in this chronic stroke cohort.

Abstract

Background and Purpose —The Wolf Motor Function Test (WMFT) is a new time-based method to evaluate upper extremity performance while providing insight into joint-specific and total limb movements. This study addresses selected psychometric attributes of the WMFT applied to a chronic stroke population. Methods —Nineteen individuals after stroke and with intact cognition and sitting balance were age- and sex-matched with 19 individuals without impairment. Subjects performed the WMFT and the upper extremity portion of the Fugl-Meyer Motor Assessment (FMA) on 2 occasions (12 to 16 days apart), with scoring performed independently by 2 random raters. Results —The WMFT and FMA demonstrated agreement ( P &lt;0.0001) between raters at each session. WMFT scores for the dominant and nondominant extremities of individuals without impairment were different ( P ≤0.05) from the more and less affected extremities of subjects after stroke. The FMA score for the more affected extremity of subjects after stroke was different ( P ≤0.05) from the dominant and nondominant extremities. However, the FMA score for the less affected upper extremity of individuals after stroke was not different ( P &gt;0.05) from the dominant and nondominant extremities of individuals without impairment. The WMFT and FMA scores were related ( P &lt;0.02) for the more affected extremity in individuals after stroke. Conclusions —The interrater reliability, construct validity, and criterion validity of the WMFT, as used in these subject samples, are supported.