title: Dimensionality and Item-Difficulty Hierarchy of the Lower Extremity Fugl-Meyer Assessment in Individuals With Subacute and Chronic Stroke.
abstract: OBJECTIVE
  To investigate the dimensionality and item-difficulty hierarchy of the Fugl-Meyer Assessment of the lower extremity (FMA-LE).
  
  
  METHODS
  Secondary analyses of data pooled from 4 existing datasets: a phase III randomized controlled trial investigating the effectiveness of body weight support and a treadmill for rehabilitation of walking poststroke, and 3 cross-sectional studies investigating the link between impaired motor performance poststroke and walking.
  
  
  METHODS
  University research centers and rehabilitation centers.
  
  
  METHODS
  A pooled sample of individuals with a stroke (N=535, men=313; mean age ± SD, 61.91±12.42y).
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  Confirmatory factor analyses (CFA) and Rasch residual principal component analysis (PCA) investigated the dimensionality of the FMA-LE. The Rasch analysis rating scale model investigated item-difficulty hierarchy of the FMA-LE.
  
  
  RESULTS
  The CFA showed adequate fit of a 3-factor model, with 2 out of 3 indices (CFA=.95; Tucker-Lewis Index=.94; root mean square error of approximation=.124) showing good model fit. Rasch PCA showed that removal of the reflex and coordination items explained 90.8% of variance in the data, suggesting that the abnormal synergy items contributed to the measurement of a unidimensional construct. However, rating scale model results revealed deviations in the item-difficulty hierarchy of the unidimensional abnormal synergy items from the originally proposed stepwise sequence of motor recovery.
  
  
  CONCLUSIONS
  Our findings suggest that the FMA-LE might represent a multidimensional construct, challenging the use of a total score of the FMA-LE to predict lower extremity motor recovery. Removal of the misfit items resulted in creation of a unidimensional scale composed of the abnormal synergy items. However, this unidimensional scale deviates from the originally proposed hierarchical ordering.
authors.affiliation: Department of Clinical and Applied Movement Sciences, University of North Florida, Jacksonville, FL. Electronic address: c.k-balasubramanian@unf.edu.
authors.forename: Chitralakshmi K
authors.initials: CK
authors.lastname: Balasubramanian
authors.affiliation: Department of Health Science and Research and Division of Physical Therapy, College of Health Profession, Medical University of South Carolina, Charleston, SC.
authors.forename: Chih-Ying
authors.initials: CY
authors.lastname: Li
authors.affiliation: Department of Health Science and Research and Division of Physical Therapy, College of Health Profession, Medical University of South Carolina, Charleston, SC; Ralph H. Johnson Veterans Affairs Medical Center, Charleston, SC.
authors.forename: Mark G
authors.initials: MG
authors.lastname: Bowden
authors.affiliation: Department of Neurology, Wake Forest University, Winston-Salem, NC.
authors.forename: Pamela W
authors.initials: PW
authors.lastname: Duncan
authors.affiliation: Department of Health Science and Research and Division of Physical Therapy, College of Health Profession, Medical University of South Carolina, Charleston, SC; Ralph H. Johnson Veterans Affairs Medical Center, Charleston, SC.
authors.forename: Steven A
authors.initials: SA
authors.lastname: Kautz
authors.affiliation: Division of Occupational Therapy, College of Health Profession, Medical University of South Carolina, Charleston, SC.
authors.forename: Craig A
authors.initials: CA
authors.lastname: Velozo
mesh_terms: D000368:Aged; D002908:Chronic Disease; D003430:Cross-Sectional Studies; D004185:Disability Evaluation; D005080:Exercise Test / Q000379:methods / Q000706:statistics & numerical data*; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D035002:Lower Extremity / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D025341:Principal Component Analysis; D011594:Psychometrics; D016032:Randomized Controlled Trials as Topic; D020127:Recovery of Function; D012189:Retrospective Studies; D020521:Stroke / Q000503:physiopathology*; D000071939:Stroke Rehabilitation; D016138:Walking
keywords: Lower extremity; Rehabilitation; Stroke