title: Field Walking Tests Are Reliable and Responsive to Exercise Training in People With Non-Cystic Fibrosis Bronchiectasis.
abstract: OBJECTIVE
  The 6-Minute Walk Test (6MWT) and Incremental Shuttle Walk Test (ISWT) are used to assess exercise capacity, but the reliability and responsiveness of these tests in individuals with non-cystic fibrosis (CF) bronchiectasis have not been determined. This study aimed to determine the reliability and responsiveness of both tests in adults with non-CF bronchiectasis.
  
  
  METHODS
  Eighty-five participants completed 2 6MWTs and 2 ISWTs in random order. Testing was repeated at the conclusion of an 8-week intervention period of exercise training. Reliability was assessed using intraclass correlation coefficients (ICC) and Bland-Altman analysis. Responsiveness was measured by effect size (ES) and standardized response mean (SRM).
  
  
  RESULTS
  At baseline, test-retest reliability was high for both tests (ICC ≥ 0.95). The mean (95% CI) increase in the 6MWT from test 1 to test 2 was 20 m (13-26 m): 3% (0-5%) change. The mean (95% CI) increase in the ISWT was 15 m (4-25m): 4% (2-6%) change. A significant learning effect persisted after 8 weeks for the 6MWT (P = .04), but not the ISWT (P = .61). The 6MWT ES was 0.32 and SRM was 0.68; for the ISWT, ES was 0.42 with SRM of 0.71.
  
  
  CONCLUSIONS
  The 6MWT and ISWT are reliable measures of exercise capacity in non-CF bronchiectasis and responsive to exercise training. The small learning effect in both measures at baseline suggests that 2 of each test are necessary to correctly assess exercise capacity. Completion of 2 6MWTs at followup may minimize the risk of underestimating a treatment effect.
authors.affiliation: Physiotherapy, Alfred Health (Drs Lee and Holland and Ms Burge), Physiotherapy, La Trobe University (Dr Holland), and Allergy, Immunology and Respiratory Medicine, Alfred Health (Dr Stirling), Melbourne, Victoria, Australia; Institute for Breathing and Sleep (Drs Lee, Holland, Hill, and McDonald and Ms Rautela), Physiotherapy (Dr Hill and Ms Rautela), and Respiratory and Sleep Medicine (Dr McDonald), Austin Health, Heidelberg, Victoria, Australia; Physiotherapy, Sir Charles Gairdner Hospital (Ms Cecins and Dr Jenkins), Lung Institute of Western Australia (Ms Cecins and Drs Thompson and Jenkins), and Pulmonary Physiology and Sleep Medicine, Sir Charles Gairdner Hospital (Dr Thompson), Nedlands, Western Australia, Australia; and Community Physiotherapy Services (Ms Cecins) and Physiotherapy and Exercise Science, Curtin University (Drs Thompson and Jenkins), Perth, Western Australia, Australia.
authors.forename: Annemarie L
authors.initials: AL
authors.lastname: Lee
authors.forename: Nola
authors.initials: N
authors.lastname: Cecins
authors.forename: Anne E
authors.initials: AE
authors.lastname: Holland
authors.forename: Catherine J
authors.initials: CJ
authors.lastname: Hill
authors.forename: Christine F
authors.initials: CF
authors.lastname: McDonald
authors.forename: Angela T
authors.initials: AT
authors.lastname: Burge
authors.forename: Linda
authors.initials: L
authors.lastname: Rautela
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Thompson
authors.forename: Robert G
authors.initials: RG
authors.lastname: Stirling
authors.forename: Sue
authors.initials: S
authors.lastname: Jenkins
mesh_terms: D001987:Bronchiectasis / Q000503:physiopathology* / Q000534:rehabilitation*; D005080:Exercise Test / Q000706:statistics & numerical data*; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption / Q000502:physiology*; D015203:Reproducibility of Results; D016138:Walking