1. Department of Internal Medicine; Maastricht University Medical Center; Maastricht Netherlands
2. Department of Rehabilitation Medicine; Centre Hospitalier Chrétien; Liège Belgium
3. Rheumatology Unit; Repatriation General Hospital; Daw Park Australia
4. Department of Clinical Immunology and Rheumatology; Amsterdam Medical Centre; Amsterdam Netherlands
5. Department of Rheumatology; Zuyderland Medical Centre; Heerlen Netherlands
6. Ottawa Hospital Research Institute, The Ottawa Hospital - General Campus; Ottawa Canada
7. Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University; Monash-Cabrini Department of Musculoskeletal Health and Clinical Epidemiology; Cabrini Health; Melbourne Australia
8. Department of Rheumatology; Leiden University Medical Center; Leiden Netherlands