PMID- 21940789
OWN - NLM
STAT- MEDLINE
DCOM- 20120207
LR  - 20220409
IS  - 1535-4970 (Electronic)
IS  - 1073-449X (Linking)
VI  - 184
IP  - 12
DP  - 2011 Dec 15
TI  - Forced vital capacity in patients with idiopathic pulmonary fibrosis: test 
      properties and minimal clinically important difference.
PG  - 1382-9
LID - 10.1164/rccm.201105-0840OC [doi]
AB  - RATIONALE: Forced vital capacity (FVC) is an established measure of pulmonary 
      function in idiopathic pulmonary fibrosis (IPF). Evidence regarding its 
      measurement properties and minimal clinically important difference (MCID) in this 
      population is limited. OBJECTIVES: To assess the reliability, validity, and 
      responsiveness of FVC and estimate the MCID in patients with IPF. METHODS: The 
      study population included all 1,156 randomized patients in two clinical trials of 
      IFN-gamma1b. FVC and other measures of functional status were measured at screening 
      or baseline and 24-week intervals thereafter. Reliability was assessed based on 
      two proximal measures of FVC, validity was assessed based on correlations between 
      FVC and other measures of functional status, and responsiveness was assessed 
      based on the relationship between 24-week changes in FVC and other measures of 
      functional status. Distribution-based and anchor-based methods were used to 
      estimate the MCID. MEASUREMENTS AND MAIN RESULTS: Correlation of 
      percent-predicted FVC between measurements (mean interval, 18 d) was high (r = 
      0.93; P < 0.001). Correlations between FVC and other parameters were generally 
      weak, with the strongest observed correlation between FVC and carbon monoxide 
      diffusing capacity (r = 0.38; P < 0.001). Correlations between change in FVC and 
      changes in other parameters were slightly stronger (range, r = 0.16-0.37; P < 
      0.001). Importantly, 1-year risk of death was more than twofold higher (P < 
      0.001) in patients with a 24-week decline in FVC between 5% and 10%. The 
      estimated MCID was 2-6%. CONCLUSIONS: FVC is a reliable, valid, and responsive 
      measure of clinical status in patients with IPF, and a decline of 2-6%, although 
      small, represents a clinically important difference.
FAU - du Bois, Roland M
AU  - du Bois RM
AD  - Imperial College, London, UK. ron@du-bois.co.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 - King, Talmadge E Jr
AU  - King TE Jr
FAU - Lancaster, Lisa
AU  - Lancaster L
FAU - Noble, Paul W
AU  - Noble PW
FAU - Sahn, Steven A
AU  - Sahn SA
FAU - Thomeer, Michiel
AU  - Thomeer M
FAU - Valeyre, Dominique
AU  - Valeyre D
FAU - Wells, Athol U
AU  - Wells AU
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Validation Study
DEP - 20110922
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 Dec 15;184(12):1329-30. PMID: 22174111
MH  - Aged
MH  - Female
MH  - Humans
MH  - Idiopathic Pulmonary Fibrosis/*diagnosis
MH  - Male
MH  - Middle Aged
MH  - Predictive Value of Tests
MH  - Prognosis
MH  - Reproducibility of Results
MH  - *Vital Capacity
EDAT- 2011/09/24 06:00
MHDA- 2012/02/09 06:00
CRDT- 2011/09/24 06:00
PHST- 2011/09/24 06:00 [entrez]
PHST- 2011/09/24 06:00 [pubmed]
PHST- 2012/02/09 06:00 [medline]
AID - 201105-0840OC [pii]
AID - 10.1164/rccm.201105-0840OC [doi]
PST - ppublish
SO  - Am J Respir Crit Care Med. 2011 Dec 15;184(12):1382-9. doi: 
      10.1164/rccm.201105-0840OC. Epub 2011 Sep 22.