1. Division of Rheumatology, Department of Medicine, Medical Faculty Hacettepe University Ankara Turkey
2. Department of Rheumatology Leiden University Medical Center Leiden The Netherlands
3. Department of Rheumatology Zuyderland Medical Center Heerlen The Netherlands
4. CEDOC, NOVA Medical School Universidade NOVA de Lisboa Lisbon Portugal
5. Department of Rheumatology, Centro Hospitalar de Lisboa Ocidental Hospital de Egas Moniz Lisboa Portugal
6. Research Group Musculoskeletal Rehabilitation Nijmegen HAN University of Applied Sciences Nijmegen The Netherlands