1. Onassis Cardiac Surgery Center, Athens, Greece
2. Joint Rheumatology, Laikon Hospital, Athens, Greece
3. Department of Pathophysiology, Laikon Hospital, National Kapodistrian University of Athens, Athens, Greece
4. Department of Internal Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
5. Naval Hospital, Athens, Greece
6. Agia Sophia Children’s Hospital, Athens, Greece
7. Rheumatology Department, University of Ioannina, Ioannina, Greece
8. Arthritis Research UK Epidemiology Unit, Manchester University, Manchester, United Kingdom