1. University Hospital of Northern Norway and UiT the Arctic University of Norway Tromso Norway
2. IRCCS Istituto Giannina Gaslini Genoa Italy
3. Norwegian University of Science and Technology and St. Olavs University Hospital of Trondheim Trondheim Norway
4. IRCCS Istituto Giannina Gaslini and Università degli Studi di Genova Genoa Italy
5. University Hospital of Northern Norway Tromso Norway
6. University of Lausanne, Lausanne, Switzerland, and University Hospital of Geneva Geneva Switzerland
7. Instituto Português de Reumatologia Lisbon Portugal
8. Hospital Universitario Clementino Fraga Filho, Universidade Federal do Rio de Janeiro Rio de Janeiro Brazil
9. Medical University Innsbruck Innsbruck Austria
10. Olgahospital, Klinikum Stuttgart Stuttgart Germany
11. Istituto Gaetano Pini Milan Italy
12. Clinical Hospital Center Sestre Milosrdnice Zagreb Croatia
13. Klinikum Bremen‐Mitte Bremen Germany
14. Aristotle University of Thessaloniki, Hippokration General Hospital Thessaloniki Greece
15. Juliane Marie Centret, Rigshospitalet Copenhagen Denmark
16. Riga Stradins University, Children University Hospital Riga Latvia
17. Academisch Ziekenhuis Leiden Leiden Netherlands
18. Pan a Aglaia Kyriakou Children’s Hospital, Athens University School of Medicine Athens Greece
19. IRCCS Burlo Garofolo, Institute for Maternal and Child Health Trieste Italy
20. Azienda Ospedaliero Universitaria Meyer Florence Italy
21. Università degli Studi di Genova Genoa Italy
22. IRCCS Istituto Giannina Gaslini, Paediatric Rheumatology International Trials Organisation Genoa Italy