Are the Hierarchical Properties of the Fugl-Meyer Assessment Scale the Same in Acute Stroke and Chronic Stroke?

Abstract

Background The motor function section of the Fugl-Meyer assessment scale (FM motor scale) is a robust scale of motor ability in people after stroke, with high predictive validity for outcome. However, the FM motor scale is time-consuming. The hierarchical properties of the upper extremity (UE) and lower extremity (LE) sections of the FM motor scale have been established in people with chronic stroke. These data support the use of a more concise method of administration and confirm scores can be legitimately summed. Objective The aim of this study was to establish that a similar hierarchy exists in people within 72 hours after stroke onset. Design A prospective, cross-sectional design was used. Methods Data were obtained from 75 eligible people in a nationwide prospective study (the Early Prediction of Functional Outcome After Stroke). The full version of both sections of the FM motor scale was administered within 72 hours after stroke onset. The hierarchy of item difficulty was investigated by applying Guttman scaling procedures within each stage and each subsection of the UE and LE sections of the scale. The scaling procedures then were applied to item difficulty between stages and subsections and finally across all scale items (stage divisions ignored) of the FM motor scale. Results For all analyses, the results exceeded acceptable levels for the coefficient of reproducibility and the coefficient of scalability. Limitations The sample was a population of people with stroke of moderate severity. Conclusions The unidimensional hierarchy of the UE and LE sections of the FM motor scale (already established for chronic stroke) within 72 hours after stroke onset was confirmed. A legitimate total summed score can indicate a person's level of motor ability.