title: Reliability, agreement, and responsiveness of a 6-minute walk/run test in patients with heart disease.
abstract: BACKGROUND
  The 6-minute walk test (6 MWT) is widely used to assess exercise tolerance in cardiac rehabilitation (CR). However, previous research shows it to be insufficiently responsive, especially for patients with a relatively high maximal exercise tolerance at baseline. We therefore designed a 6-minute walk/run test (6 MWRT), which has the same duration as the 6 MWT but allows running. The objective of this study was to determine the test-retest reproducibility and responsiveness of this 6 MWRT.
  
  
  METHODS
  Responsiveness was investigated in a prospective cohort study among a group of patients entering CR at Maastricht University Medical Center, with a cross-sectional part to assess the test-retest reproducibility.
  
  
  METHODS
  Test-retest reproducibility (reliability and agreement) was investigated using the intraclass correlation (ICC) and a Bland-Altman plot of two measurements implemented in the first week of rehabilitation. Responsiveness of the 6 MWT and the 6 MWRT was calculated using the standard response mean (SRM) over a 6-week period.
  
  
  RESULTS
  The first reproducibility analysis included 34 patients, the second 22 patients. The ICCs were 0.935 and 0.906, respectively, with limits of agreement of ± 79 and ± 61 m. The responsiveness analysis included 27 patients. The SRM values were 0.83 for the 6 MWT and 0.71 for the 6 MWRT.
  
  
  CONCLUSIONS
  Although the 6 MWRT is a reproducible test in CR, its responsiveness is not superior to that of the 6 MWT. We therefore prefer the conventional 6 MWT as an evaluative measurement in CR and advise against using the 6 MWRT as (evaluative) measurement in CR for this purpose.
authors.affiliation: Maastricht University Medical Center, Maastricht, The Netherlands. Maastricht University, Maastricht, The Netherlands. Danielle.berghmans@mumc.nl
authors.forename: Danielle D
authors.initials: DD
authors.lastname: Berghmans
authors.forename: Antoine F
authors.initials: AF
authors.lastname: Lenssen
authors.forename: Carolien H
authors.initials: CH
authors.lastname: Bastiaenen
authors.forename: Mustafa
authors.initials: M
authors.lastname: Ilhan
authors.forename: Nicole H
authors.initials: NH
authors.lastname: Lencer
authors.forename: George M
authors.initials: GM
authors.lastname: Roox
mesh_terms: D000328:Adult; D000368:Aged; D015331:Cohort Studies; D003327:Coronary Disease / Q000503:physiopathology* / Q000534:rehabilitation; D003430:Cross-Sectional Studies; D005080:Exercise Test / Q000379:methods* / Q000592:standards; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015203:Reproducibility of Results; D012420:Running; D016138:Walking