1. First Department of Respiratory and Critical Care Medicine and Ludwig Boltzmann Institute for COPD and Respiratory Epidemiology, Otto Wagner Hospital, Vienna, Austria
2. Medical School, Sigmund Freud University, Vienna, Austria
3. Second Medical Department with Pneumology, Wilhelminenspital, Vienna, Austria
4. Second Department of Respiratory and Critical Care Medicine and Ludwig Boltzmann Institute for COPD and Respiratory Epidemiology, Otto Wagner Hospital, Vienna, Austria
5. Department of Pneumology, Salzburger Landeskliniken, Paracelsus Medical University, Salzburg, Austria
6. Department of Thoracic Surgery and Karl Landsteiner Institute for Thoracic Oncology, Otto Wagner Hospital, Vienna, Austria
7. Department of Radio-Oncology, Wilhelminenspital, Vienna, Austria
8. Department of Pneumology, General Hospital Linz, Linz, Austria
9. Department of Pneumology, Klinikum Wels-Grieskirchen, Wels, Austria
10. Department of Internal Medicine, Krankenhaus der Barmherzigen Schwestern Ried/Innkreis, Ried im Innkreis, Austria
11. Department of Pneumology, Krankenhaus der Elisabethinen, Linz, Austria
12. Department of Pneumology, Klinikum Steyr, Steyr, Austria
13. Department of Pneumology and Respiratory Diseases, Krankenhaus Hietzing-Rosenhügel, Vienna, Austria
14. Department of Pulmonology, Landesklinikum Hochegg, Hochegg, Austria
15. Clinical Department of Pneumology, Landesklinikum Krems, Krems, Austria
16. Department of Pulmonology, Landeskrankenhaus Hohenems, Hohenems, Austria
17. Department of Pulmonology, Salzkammergut Klinikum Vöcklabruck, Vöcklabruck, Austria