1. Pulmonary Unit, HUS Porvoo Hospital , Porvoo , Finland
2. Doctoral Programme of Clinical Research, University of Helsinki , Helsinki , Finland
3. Centre for Musculoskeletal Diseases, Tampere University Hospital , Tampere , Finland
4. Faculty of Medicine and Health Technology, Tampere University , Tampere , Finland
5. Medaffcon Oy , Espoo , Finland
6. Department of Pulmonary Diseases and Clinical Allergology, University of Turku , Turku , Finland
7. Finnish Lung Health Association (Filha) , Helsinki , Finland