PMID- 21131468
OWN - NLM
STAT- MEDLINE
DCOM- 20110711
LR  - 20220409
IS  - 1535-4970 (Electronic)
IS  - 1073-449X (Linking)
VI  - 183
IP  - 9
DP  - 2011 May 1
TI  - Six-minute-walk test in idiopathic pulmonary fibrosis: test validation and 
      minimal clinically important difference.
PG  - 1231-7
LID - 10.1164/rccm.201007-1179OC [doi]
AB  - RATIONALE: The 6-minute-walk test (6MWT) is a practical and clinically meaningful 
      measure of exercise tolerance with favorable performance characteristics in 
      various cardiac and pulmonary diseases. Performance characteristics in patients 
      with idiopathic pulmonary fibrosis (IPF) have not been systematically evaluated. 
      OBJECTIVES: To assess the reliability, validity, and responsiveness of the 6MWT 
      and estimate the minimal clinically important difference (MCID) in patients with 
      IPF. METHODS: The study population included all subjects completing a 6MWT in a 
      clinical trial evaluating interferon gamma-1b (n = 822). Six-minute walk distance 
      (6MWD) and other parameters were measured at baseline and at 24-week intervals 
      using a standardized protocol. Parametric and distribution-independent 
      correlation coefficients were used to assess the strength of the relationships 
      between 6MWD and measures of pulmonary function, dyspnea, and health-related 
      quality of life. Both distribution-based and anchor-based methods were used to 
      estimate the MCID. MEASUREMENTS AND MAIN RESULTS: Comparison of two proximal 
      measures of 6MWD (mean interval, 24 d) demonstrated good reliability (coefficient 
      = 0.83; P < 0.001). 6MWD was weakly correlated with measures of physiologic 
      function and health-related quality of life; however, values were consistently 
      and significantly lower for patients with the poorest functional status, 
      suggesting good construct validity. Importantly, change in 6MWD was highly 
      predictive of mortality; a 24-week decline of greater than 50 m was associated 
      with a fourfold increase in risk of death at 1 year (hazard ratio, 4.27; 95% 
      confidence interval, 2.57- 7.10; P < 0.001). The estimated MCID was 24-45 m. 
      CONCLUSIONS: The 6MWT is a reliable, valid, and responsive measure of disease 
      status and a valid endpoint for clinical trials in IPF.
FAU - du Bois, Roland M
AU  - du Bois RM
AD  - National Heart & Lung Institute, Imperial College, London, United Kingdom. 
      r.dubois@imperial.ac.uk
FAU - Weycker, Derek
AU  - Weycker D
FAU - Albera, Carlo
AU  - Albera C
FAU - Bradford, Williamson Z
AU  - Bradford WZ
FAU - Costabel, Ulrich
AU  - Costabel U
FAU - Kartashov, Alex
AU  - Kartashov A
FAU - Lancaster, Lisa
AU  - Lancaster L
FAU - Noble, Paul W
AU  - Noble PW
FAU - Sahn, Steven A
AU  - Sahn SA
FAU - Szwarcberg, Javier
AU  - Szwarcberg J
FAU - Thomeer, Michiel
AU  - Thomeer M
FAU - Valeyre, Dominique
AU  - Valeyre D
FAU - King, Talmadge E Jr
AU  - King TE Jr
LA  - eng
PT  - Clinical Trial, Phase III
PT  - Journal Article
PT  - Randomized Controlled Trial
PT  - Research Support, Non-U.S. Gov't
PT  - Validation Study
DEP - 20101203
PL  - United States
TA  - Am J Respir Crit Care Med
JT  - American journal of respiratory and critical care medicine
JID - 9421642
SB  - IM
CIN - Am J Respir Crit Care Med. 2011 May 1;183(9):1122-4. PMID: 21531951
MH  - Aged
MH  - Dyspnea/etiology/physiopathology
MH  - Exercise Test/*methods
MH  - Female
MH  - Humans
MH  - Idiopathic Pulmonary Fibrosis/complications/*diagnosis/physiopathology
MH  - Lung/physiopathology
MH  - Male
MH  - Middle Aged
MH  - Predictive Value of Tests
MH  - Quality of Life
MH  - Reproducibility of Results
MH  - *Walking
EDAT- 2010/12/07 06:00
MHDA- 2011/07/12 06:00
CRDT- 2010/12/07 06:00
PHST- 2010/12/07 06:00 [entrez]
PHST- 2010/12/07 06:00 [pubmed]
PHST- 2011/07/12 06:00 [medline]
AID - 201007-1179OC [pii]
AID - 10.1164/rccm.201007-1179OC [doi]
PST - ppublish
SO  - Am J Respir Crit Care Med. 2011 May 1;183(9):1231-7. doi: 
      10.1164/rccm.201007-1179OC. Epub 2010 Dec 3.