1. Rheumatology Unit, Department of Medical Sciences, Università degli Studi di Ferrara, Azienda Ospedaliero-Universitaria S. Anna , Cona, Italy
2. Division of Internal Medicine II, Centro Hospitalar Universitário Lisboa Norte , Lisbon, Portugal
3. Instituto de Semiótica Clínica, Faculty of Medicine, University of Lisbon , Lisbon, Portugal
4. Centre for Rheumatology, Department of Medicine, University College London , London, UK