[1] Univ Alberta, Div Pulm Med, Edmonton, AB, Canada
[2] Univ Milan, Bicocca S Gerardo Hosp, Resp Dis Unit, Monza, Italy
[3] Univ Hosp Policlin G Rodol San Marco, Reg Referral Ctr Rare Lung Dis, Catania, Italy
[4] Univ Catania, Univ Hosp Policlin G Rodol San Marco, Reg Referral Ctr Rare Lung Dis, Dept Clin & Expt Med, Catania, Italy
[5] Univ Padua, Dept Cardiac Thorac Vasc Sci & Publ Hlth, Padua, Italy
[6] Fdn Policlin A Gemelli IRCCS, UOC Pneumol, Rome, Italy
[7] Ege Univ Hospiral, Dept Pulmonol, Izmir, Turkey
[8] ARNAS Osped Civ Cristina Benfratelli, UOSD UTIR, Palermo, Italy
[9] Siena Univ, Resp Dis Unit, Siena, Italy
[10] Royal Brompton Hosp, Imperial Coll, Interstitial Lung Dis Unit, London, England
[11] Univ Duisburg Essen, Ruhrlandklin Univ Hosp, Ctr Interstitial & Rare Lung Dis, Pneumol Dept, Essen, Germany
[12] Louis Pradel Hosp, Hosp Civils Lyon, Natl Reference Coordinating Ctr Rare Pulm Dis, Dept Resp Med, Lyon, France
[13] Univ Lyon, IVPC, INRAE, Lyon, France
[14] Univ Autonoma Madrid, Hosp Univ Princesa, Pulmonol Dept, Madrid, Spain
[15] Univ Med Ctr Rotterdam, Ctr Excellence, Erasmus MC, Interstitial Lung Dis & Sarcoidosis, Rotterdam, Netherlands
[16] Aarhus Univ Hosp, Ctr Rare Lung Dis, Dept Resp Dis & Allergy, Aarhus N, Denmark