title: Timed 25-foot walk: direct evidence that improving 20% or greater is clinically meaningful in MS.
abstract: OBJECTIVE
  In this study, we used data from clinical trials of dalfampridine (fampridine outside the United States) to re-examine the clinical meaningfulness of Timed 25-Foot Walk (T25FW) changes.
  
  
  METHODS
  Pooled data were analyzed from 2 phase III randomized placebo-controlled clinical trials of dalfampridine in multiple sclerosis (MS) (n = 533). Walking speed (T25FW) and patient-reported walking ability (MS Walking Scale-12 [MSWS-12]) were measured, concurrently, multiple times before and during treatment. We examined T25FW speed variability within and between visits, correlations of T25FW speed with MSWS-12 score, and changes in MSWS-12 (mean scores, effect sizes) associated with percent T25FW changes.
  
  
  RESULTS
  T25FW speed variability was small (within- and between-visit averages = 7.2%-8.7% and 14.4%-16.3%). Correlations between T25FW and MSWS-12 values were low (-0.20 to -0.30), but relatively stronger between their change values (-0.33 to -0.41). Speed improvements of >20%, and possibly 15%, were associated with clinically meaningful changes in self-reported walking ability using MSWS-12 change score and effect size criteria.
  
  
  CONCLUSIONS
  This study builds on existing research and provides direct evidence that improvements in T25FW speed of ≥ 20% are meaningful to people with MS. The dalfampridine data enabled examinations previously not possible, including spontaneous and induced speed changes, speed change anchored to change in self-reported walking ability, and a profile of speed changes. Results support the T25FW as a clinically meaningful outcome measure for MS clinical trials.
authors.affiliation: Plymouth University Peninsula Schools of Medicine and Dentistry, Devon, UK. jeremy.hobart@pms.ac.uk
authors.forename: Jeremy
authors.initials: J
authors.lastname: Hobart
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Blight
authors.forename: Andrew
authors.initials: A
authors.lastname: Goodman
authors.forename: Frances
authors.initials: F
authors.lastname: Lynn
authors.forename: Norman
authors.initials: N
authors.lastname: Putzki
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015761:4-Aminopyridine / Q000627:therapeutic use; D017326:Clinical Trials, Phase III as Topic; D005684:Gait / Q000502:physiology; D020233:Gait Disorders, Neurologic / Q000175:diagnosis / Q000188:drug therapy; D009103:Multiple Sclerosis / Q000175:diagnosis / Q000188:drug therapy; D009460:Neurologic Examination / Q000379:methods; D026902:Potassium Channel Blockers / Q000627:therapeutic use; D016032:Randomized Controlled Trials as Topic; D015203:Reproducibility of Results; D016138:Walking / Q000502:physiology
chemical_list: D015761:4-Aminopyridine; D026902:Potassium Channel Blockers