1. Department of Pulmonary Medicine, Porvoo Hospital, Porvoo, Finland;
2. Doctoral Programme of Clinical Research, University of Helsinki, Helsinki, Finland;
3. Department of Surgery, Porvoo Hospital, Porvoo, Finland;
4. Department of Pulmonary Diseases and Clinical Allergology, University of Turku, Turku, Finland;
5. Finnish Lung Health Association (FILHA), Helsinki, Finland