title: Validity and reliability of the community balance and mobility scale in individuals with knee osteoarthritis.
abstract: BACKGROUND
  There is a high incidence of falls in older adults with knee osteoarthritis (OA). Adequate dynamic balance and mobility reduce the risk of falls; however, there are currently no validated, advanced tests of dynamic balance and mobility for individuals with knee OA.
  
  
  OBJECTIVE
  The purpose of this study was to determine the convergent validity, known-groups validity, and test-retest reliability of a dynamic test of balance and mobility, the Community Balance and Mobility Scale (CB&M), in a knee OA population.
  
  
  METHODS
  A cross-sectional design was used.
  
  
  METHODS
  Twenty-five individuals aged 50 years and older with medial knee OA and an equal number of healthy controls completed the CB&M and other tests of balance and mobility, including the Berg Balance Scale, the Timed "Up & Go" Test, a test of maximal single-leg stance time, and the 10-Meter Walk Test (self-selected and fast walking speed). Convergent validity of balance tests with the CB&M was assessed using Pearson product moment correlation coefficients, and known-groups validity was assessed using independent t tests. Test-retest reliability of the CB&M was assessed using intraclass correlation coefficients (ICCs) and standard error of measurement (SEM).
  
  
  RESULTS
  Scores on the CB&M were significantly correlated with all measures of balance and mobility for those with knee OA. There were significant differences in CB&M scores between groups. Scores on the CB&M were highly reliable in people with knee OA (ICC=.95, 95% confidence interval [95% CI]=0.70 to 0.99; SEM=3, 95% CI=2.68 to 4.67).
  
  
  CONCLUSIONS
  Few participants had severe knee OA.
  
  
  CONCLUSIONS
  The CB&M displayed moderate convergent validity, excellent known-groups validity, and high test-retest reliability. The CB&M can be used as a valid and reliable tool to assess dynamic balance and mobility deficits in people with knee OA.
authors.affiliation: J. Takacs, MSc, Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Judit
authors.initials: J
authors.lastname: Takacs
authors.affiliation: S.J. Garland, PT, PhD, Department of Physical Therapy, University of British Columbia.
authors.forename: S Jayne
authors.initials: SJ
authors.lastname: Garland
authors.affiliation: M.G. Carpenter, PhD, School of Kinesiology, University of British Columbia.
authors.forename: Mark G
authors.initials: MG
authors.lastname: Carpenter
authors.affiliation: M.A. Hunt, PT, PhD, Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3. michael.hunt@ubc.ca.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Hunt
mesh_terms: D000368:Aged; D003430:Cross-Sectional Studies; D005080:Exercise Test / Q000379:methods*; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000503:physiopathology*; D004856:Postural Balance / Q000502:physiology*; D015203:Reproducibility of Results