1. Department of Rheumatology, VU University Medical Center, Amsterdam, The Netherlands
2. Department of Rheumatology, Amsterdam Medical Center, Amsterdam, The Netherlands
3. Department of Clinical Chemistry, VU University Medical Center, Amsterdam, The Netherlands
4. Reade, Amsterdam, The Netherlands
5. Department of Rheumatology, Maartenskliniek, Woerden, The Netherlands
6. Department of Epidemiology and Biostatistics, VU University Medical Center, Amsterdam, The Netherlands
7. Department of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands