1. Rheumatology Department, Leiden University Medical Centre, Leiden, The Netherlands
2. Rheumatology Department, Cochin Hospital, Assistance Publique Hôpitaux de Paris
3. INSERM (U1153) Clinical Epidemiology and Biostatistics, University of Paris, Paris, France
4. Rheumatology Department, Reina Sofia University Hospital, Maimonides Institute of Biomedical Research of Cordoba, Cordoba, Spain