[1] Univ Oxford, Nuffield Dept Med Expt Med, Resp Med Unit, Oxford, England
[2] Univ Oxford, Natl Inst Hlth Res NIHR Oxford Biomed Res Ctr BRC, Oxford, England
[3] Edith Cowan Univ, Sch Med & Hlth Sci, Perth, WA, Australia
[4] Katholieke Univ Leuven, Dept Resp Dis, Res Grp BREATHE, UZ Leuven, Leuven, Belgium
[5] Univ Paris, Fac Med, Paris, France
[6] Cochin Hosp, AP HP, INSERM 1016 Inst Cochin, Paris, France
[7] Univ Ferrara, Dept Morphol Surg & Expt Med, Ferrara, Italy
[8] Maastricht Univ, Dept Resp Med, Med Ctr, Maastricht, Netherlands
[9] NIHR Leicester Biomed Res Ctr Resp, Glenfield Hosp, Dept Resp Sci, Leicester, Leics, England
[10] Philipps Univ, Univ Med Ctr Giessen & Marburg, German Ctr Lung Res DZL, Dept Med Pulm & Crit Care Med, Marburg, Germany
[11] IDIBAPS August Pi I Sunyer Biomed Res Inst, Pulm & Crit Care Div, Clin Sagrada Familia, Barcelona, Spain
[12] McMaster Univ, Dept Hlth Res Methods Evidence & Impact, Hamilton, ON, Canada
[13] Imperial Coll, Natl Heart & Lung Inst, London, England
[14] Sahlgrens Univ Hosp, COPD Ctr, Dept Internal Med & Clin Nutr, Inst Med,SU Sahlgrenska,Dept Resp Med & Allergol, Gothenburg, Sweden
[15] German Ctr Lung Res DZL, Airway Res Ctr North ARCN, Pulm Res Inst, LungenClin Grosshansdorf, Grosshansdorf, Germany