1. Department of Rheumatology, University of Paris VI-Pierre et Marie Curie, Hospital Pitié-Salpêtrière, Paris, France, Division of Clinical Epidemiology, McGill University Health Center, Montreal, QC, Canada, EA 3444, School of Public Health, Faculty of Medicine, Nancy, France, -hop-paris.fr
2. Division of Clinical Epidemiology, McGill University Health Center, Montreal, QC, Canada
3. EA 3444, School of Public Health, Faculty of Medicine, Nancy, France
4. Department of Rheumatology, University of Toronto, Toronto, ON, Canada
5. Department of Rheumatology, McGill University Health Center, Montreal, QC, Canada
6. Institute of Health and Society, University of Newcastle, UK