[1] Aarhus Univ Hosp, Dept Resp Dis & Allergy, Ctr Rare Lung Dis, Aarhus, Denmark
[2] Mayo Clin Rochester, Div Pulm & Crit Care Med, Rochester, MN USA
[3] Kurume Univ, Sch Med, Dept Internal Med, Div Respirol Neurol & Rheumatol, Kurume, Fukuoka, Japan
[4] Careggi Univ Hosp, Dept Expt & Clin Med, Florence, Italy
[5] Univ Autonoma Madrid, Hosp Univ Princesa, Madrid, Spain
[6] Univ Hosp Leuven, Dept Pulm Med, Unit Interstitial Lung Dis, Leuven, Belgium
[7] Mainanalytics GmbH, Sulzbach, Taunus, Germany
[8] Boehringer Ingelheim Int GmbH, Ingelheim, Germany
[9] Univ Duisburg Essen, Pneumol Dept, Ctr Interstitial & Rare Lung Dis, Ruhrlandklin, Essen, Germany