Development of a Short Form Assessment of Upper Extremity Motor Ability for Individuals Post Stroke

Abstract

Research Objectives To develop a short form assessment that combines items from the Fugl Meyer Assessment-Upper Extremity (FMA) and the Wolf Motor Function Test (WMFT) to provide a more comprehensive and precise measure of UE motor ability post stroke. Design We used a convenience sample of pre-intervention data from two upper extremity rehabilitation trials conducted with stroke survivors. Factor analysis and the Rasch rating scale model were applied to examine the properties of the full item bank prior to the development of the short form. Setting Outpatient, academic research center. Participants Data were pooled since the parent studies had similar eligibility criteria. Participants were included in the studies if they experienced a stroke ≥ 3 months prior and had UE hemiparesis. Participants were excluded if they had severe hemiparesis, severe spasticity (Modified Ashworth Scale >3 in elbow, wrist, or fingers), or reported UE pain. 167 individuals with stroke who completed both the WMFT and FMA were included. Interventions N/A. Main Outcome Measures Data from the 30-item FMA and the 15-item WMFT (rating scale score) were analyzed using factor analysis to ensure unidimensionality. Item response theory methodologies were used to develop the short form. The Rasch rating scale model was applied to examine the measurement properties. Results A 15-item short form was developed. Item infit statistics (Mnsq) ranged from 0.63-1.35 and point measure correlations ranged from 0.39-0.90. Person reliability was 0.93 and the person separation index was 3.7 indicating the measure can separate between 5 statistically different strata. Conclusions Items from the FMA and WMFT can be combined to provide a precise measure of UE motor ability. The short form demonstrated acceptable psychometric properties. Author(s) Disclosures The authors have no conflicts of interest to disclose. To develop a short form assessment that combines items from the Fugl Meyer Assessment-Upper Extremity (FMA) and the Wolf Motor Function Test (WMFT) to provide a more comprehensive and precise measure of UE motor ability post stroke. We used a convenience sample of pre-intervention data from two upper extremity rehabilitation trials conducted with stroke survivors. Factor analysis and the Rasch rating scale model were applied to examine the properties of the full item bank prior to the development of the short form. Outpatient, academic research center. Data were pooled since the parent studies had similar eligibility criteria. Participants were included in the studies if they experienced a stroke ≥ 3 months prior and had UE hemiparesis. Participants were excluded if they had severe hemiparesis, severe spasticity (Modified Ashworth Scale >3 in elbow, wrist, or fingers), or reported UE pain. 167 individuals with stroke who completed both the WMFT and FMA were included. N/A. Data from the 30-item FMA and the 15-item WMFT (rating scale score) were analyzed using factor analysis to ensure unidimensionality. Item response theory methodologies were used to develop the short form. The Rasch rating scale model was applied to examine the measurement properties. A 15-item short form was developed. Item infit statistics (Mnsq) ranged from 0.63-1.35 and point measure correlations ranged from 0.39-0.90. Person reliability was 0.93 and the person separation index was 3.7 indicating the measure can separate between 5 statistically different strata. Items from the FMA and WMFT can be combined to provide a precise measure of UE motor ability. The short form demonstrated acceptable psychometric properties.