title: Clinical Functional Capacity Testing in Patients With Facioscapulohumeral Muscular Dystrophy: Construct Validity and Interrater Reliability of Antigravity Tests.
abstract: OBJECTIVE
  To evaluate the construct validity and interrater reliability of 4 simple antigravity tests in a small group of patients with facioscapulohumeral muscular dystrophy (FSHD).
  
  
  METHODS
  Case-control study.
  
  
  METHODS
  University medical center.
  
  
  METHODS
  Patients with various severity levels of FSHD (n=9) and healthy control subjects (n=10) were included (N=19).
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  A 4-point ordinal scale was designed to grade performance on the following 4 antigravity tests: sit to stance, stance to sit, step up, and step down. In addition, the 6-minute walk test, 10-m walking test, Berg Balance Scale, and timed Up and Go test were administered as conventional tests. Construct validity was determined by linear regression analysis using the Clinical Severity Score (CSS) as the dependent variable. Interrater agreement was tested using a κ analysis.
  
  
  RESULTS
  Patients with FSHD performed worse on all 4 antigravity tests compared with the controls. Stronger correlations were found within than between test categories (antigravity vs conventional). The antigravity tests revealed the highest explained variance with regard to the CSS (R(2)=.86, P=.014). Interrater agreement was generally good.
  
  
  CONCLUSIONS
  The results of this exploratory study support the construct validity and interrater reliability of the proposed antigravity tests for the assessment of functional capacity in patients with FSHD taking into account the use of compensatory strategies. Future research should further validate these results in a larger sample of patients with FSHD.
authors.affiliation: Department of Rehabilitation, Donders Centre for Neuroscience, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: Noortje H
authors.initials: NH
authors.lastname: Rijken
authors.affiliation: Department of Neurology, Donders Centre for Neuroscience, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: Baziel G
authors.initials: BG
authors.lastname: van Engelen
authors.affiliation: Department of Rehabilitation, Donders Centre for Neuroscience, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: Vivian
authors.initials: V
authors.lastname: Weerdesteyn
authors.affiliation: Department of Rehabilitation, Donders Centre for Neuroscience, Radboud University Medical Centre, Nijmegen, The Netherlands. Electronic address: Sander.Geurts@radboudumc.nl.
authors.forename: Alexander C
authors.initials: AC
authors.lastname: Geurts
mesh_terms: D000046:Academic Medical Centers; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020391:Muscular Dystrophy, Facioscapulohumeral / Q000534:rehabilitation*; D015588:Observer Variation; D026741:Physical Therapy Modalities; D004856:Postural Balance; D015203:Reproducibility of Results; D016138:Walking
keywords: Mobility limitation; Neuromuscular diseases; Rehabilitation