1. Institute for Regional Health Research, University of Southern Denmak, Odense, Denmark;
2. University College of Southern Denmark, Institute for health Education, Aabenraa, Denmark;
3. King Christian Xth Hospital for Rheumatic Diseases, Graaasten, Denmark;
4. Department of Medicine and Health Technology, Aalborg University;
5. Department of Public Health, University of Southern Denmark, Esbjerg, Denmark;
6. Hospital of Southern Denmark, Aabenraa, Denmark