1 Patient Research Partner, EULAR, Zaltbommel, Netherlands martinusdewit@hotmail.com.
2 School of Public Health, Nancy, France.
3 Universite de Lorraine, APEMAC, School of Public Health, Nancy, France.
4 Maastricht University Medical Centre+, Maastricht, Netherlands.
5 Department of Internal Medicine, Division of Rheumatology, Maastricht University Medical Center, and the Caphri Research Institute Maastricht University, Maastricht, Netherlands.
6 Rheumatology, Assistance Publique - Hopitaux De Paris, Paris, France.
7 GRC08 - Iplesp, UPMC Faculte De Medecine, Paris, France.