1. Respiratory Medicine Unit, Institute of Clinical Medicine, Oulu University Hospital, MRC Oulu, Finland
2. Turku University Hospital, Division of Medicine, Department of Pulmonary Diseases and Sleep Research Centre, Department of Pulmonary Diseases and Clinical Allergology, University of Turku, Turku, Finland
3. Medical Informatics and Statistics Research Group, University of Oulu, Oulu, Finland
4. Department of Neurology, Oulu University Hospital and University of Oulu, Oulu, Finland