1. 4th Department of Internal Medicine, Attikon University Hospital, Joint Rheumatology Program, National and Kapodistrian University of Athens Medical School, Athens, Greece
2. Division of Rheumatology, Department of Medicine Solna, Karolinska Institutet and Rheumatology, Karolinska University Hospital, Stockholm, Sweden
3. Department of Rheumatology, Clinical Rheumatology and Allergy, University of Crete Medical School, Iraklio, Greece