1. Department of Paediatrics, Hacettepe University, Ankara, Turkey
2. Great Ormond Street Hospital for Children NHS Foundation Trust, University College London Great Ormond Street Institute of Child Health, London, UK
3. Wilhelmina Children’s Hospital, University Medical Center, Utrecht
4. Sophia Children’s Hospital, Erasmus University Medical Centre, Rotterdam, The Netherlands
5. Department of Paediatric Rheumatology, Alder Hey Children’s NHS Foundation Trust, Liverpool, UK
6. Department of Paediatric Rheumatology, University Children’s Hospital Ljubljana, Ljubljana, Slovenia
7. Necker Hospital, Assistance Publique-Hôpitaux de Paris, Paris, France
8. General University Hospital and 1 Faculty of Medicine, Charles University, Prague, Czech Republic
9. The Hospital for Sick Children, University of Toronto, Toronto, Canada
10. Department of Paediatric Rheumatology, Bicêtre University Hospital, Paris, France
11. Hospital for Children and Adolescents, University of Helsinki, Helsinki, Finland
12. Gaslini Children’s Hospital, Genoa, Italy
13. Meir Medical Centre, Tel Aviv University, Tel Aviv, Israel
14. Institute of Translational Medicine, University of Liverpool and Alder Hey children's NHS Foundation Trust, Members of Liverpool Health Partners, Liverpool, UK