1. Centre for Rheumatology and Clinical Immunology, Division of Medicine, Turku University Hospital, Turku, Finland
2. Department of Medicine, University of Turku, Turku, Finland
3. Division of Rheumatology, Department of Internal Medicine, Oulu University Hospital, Oulu, Finland
4. Department of Biostatistics, University of Turku, Turku, Finland
5. Cancer Research and Translational Medicine Research Unit, Medical Research Center Oulu, University of Oulu, Oulu, Finland
6. Division of Rheumatology, Department of Internal Medicine, Kuopio University Hospital, Kuopio, Finland