1. Università degli Studi di Genova Genoa Italy
2. Wilhelmina Children’s Hospital, Utrecht, The Netherlands, and Istituto Giannina Gaslini, IRCCS and Clinica Pediatrica e Reumatologia Genoa Italy
3. Istituto Giannina Gaslini IRCCS and Clinica Pediatrica e Reumatologia Genoa Italy
4. Wilhelmina Children’s Hospital Utrecht The Netherlands
5. V. A. Nasonova Research Institute of Rheumatology Moscow Russia
6. New Children’s Hospital and Helsinki University Hospital Helsinki Finland
7. National Institute of Geriatrics Rheumatology, and Rehabilitation Warsaw Poland
8. University Children’s Hospital and University Medical Centre Ljubljana Ljubljana Slovenia
9. Université Paris‐Descartes Institut IMAGINE Centre de Référence National pour les Rhumatismes Inflammatoires et les Maladies Auto‐Immunes Systémiques Rares de l’Enfant (RAISE) Hôpital Necker‐Enfants Malades AP‐HP Paris France
10. Children’s Hospital Affiliate of Vilnius University Hospital Santaros Clinic and Clinic of Children’s Diseases Vilnius University Vilnius Lithuania
11. Meir Medical Centre and Kfar Saba and Sackler School of Medicine Tel Aviv University Tel Aviv Israel
12. Tartu University Hospital Children’s Clinic, and University of Tartu Institute of Clinical Medicine Tartu Estonia
13. Pavol Jozef Šafárik University in Košice Kosice Slovakia
14. Ramathibodi Hospital and Mahidol University Bangkok Thailand
15. Charles University in Prague and General University Hospital Prague Czech Republic
16. Seattle Children’s Hospital Seattle Washington
17. Università degli Studi di Genova Istituto Giannina Gaslini IRCCS and Clinica Pediatrica e Reumatologia, Genoa, Italy, and Sechenov First Moscow State Medical University Moscow Russia
18. Università degli Studi di Genova Istituto Giannina Gaslini IRCCS and Clinica Pediatrica e Reumatologia Genoa Italy