title: Self-selected walking speed was consistent when recorded while using a cane.
abstract: OBJECTIVE
  To assess whether loss of consistency or systematic measurement error is introduced by allowing older individuals to use a cane during measurement of self-selected walking speed (SSWS).
  
  
  METHODS
  Observational study of women aged 65+ (Women's Health and Aging Study I, n=1,002).
  
  
  RESULTS
  Of individuals who use a cane in daily life, 201 (50.76%) did not use an aid during testing. The Coefficient of Variation was low in individuals who reported cane use in daily life but did not use one in testing (10.72%), and did not vary substantially if a cane was used (12.04%). The Intra-Class Correlation Coefficient was high: 0.958 for those who reported cane use in daily life but did not use one during testing and 0.962 for those who used a cane. In both groups, Bland-Altman plots revealed a small systematic difference between the first and second trials. There was no evidence of effect modification of the association between SSWS and mobility disability by cane use during testing.
  
  
  CONCLUSIONS
  This observational study found neither evidence of poorer consistency nor increased measurement bias in SSWS recorded while using a cane compared to using no assistive device.
authors.affiliation: Division of Geriatric Medicine & Gerontology, Johns Hopkins School of Medicine, Baltimore, MD 21224-2734, USA. cweiss9@jhmi.edu
authors.forename: Carlos O
authors.initials: CO
authors.lastname: Weiss
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Seplaki
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Wolff
authors.forename: Judith D
authors.initials: JD
authors.lastname: Kasper
authors.forename: Emily M
authors.initials: EM
authors.lastname: Agree
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D002183:Canes / Q000706:statistics & numerical data*; D051341:Dependent Ambulation / Q000706:statistics & numerical data*; D004185:Disability Evaluation; D005260:Female; D015577:Geriatric Assessment; D006801:Humans; D051346:Mobility Limitation; D015203:Reproducibility of Results; D016138:Walking / Q000502:physiology*