Table 1 Details of collaborative groups and partner organisations

Juvenile Dermatomyositis Research Group, JDRG (UK and Ireland) [18]

Multi-disciplinary healthcare professionals and scientists in the field of Paediatric Rheumatology; representative of all major UK paediatric rheumatology centres. JDRG members are all contributors to, and investigators in, the Juvenile Dermatomyositis Cohort and Biomarker Study, JDCBS [8]

UK and Ireland

▪ Delphi survey Email distribution

▪ Representation in NGT meeting

▪ Scrutinising data collection (Stage 3)

▪ Aid dissemination of study results

▪ Steering committee – study oversight

▪ Patient/parent representation: steering committee and facilitated groups

Childhood Arthritis and Rheumatology Research Alliance, CARRA [17]

Paediatric rheumatologists and researchers throughout North America (n > 390); a proportion of whom have an interest in JDM and others more experienced in other areas of paediatric rheumatology

North America

▪ Delphi surveys Email distribution

▪ Representation in NGT meeting and provisional minimal dataset

▪ Aid dissemination of study results

Paediatric Rheumatology INternational Trials Organisation, PRINTO [7]

International research network with the aim of coordinating clinical trials and outcome studies in paediatric rheumatology

Initially a European collaboration but now includes > 50 countries and > 350 centres worldwide

▪ Delphi surveys via E-mail distribution

▪ Representation in NGT meeting and provisional minimal dataset

▪ Aid dissemination of study results

Paediatric Rheumatology European Society, PReS [19]

European scientific society for healthcare professionals in the field of paediatric rheumatology. The PReS JDM working group is a sub-group of this organisation that invites individuals with an interest or expertise in JDM

All European countries (EU and non-EU), extended to the Middle East. Associate members welcome worldwide

▪ Delphi surveys via Email distribution

▪ Representation in NGT meeting

▪ Aid dissemination of study results

International Myositis Assessment and Clinical Studies group, IMACS [4]

Coalition of healthcare providers and researchers with an interest in myositis syndromes. Myositis syndromes include JDM but also other inflammatory myopathies that are more common in adult patients

Part of the NIH science research programme, USA but welcomes members globally

▪ Delphi surveys via Email distribution

▪ Representation in NGT meeting

▪ Aid dissemination of study results

Euromyositis [39, 40]

European initiative leading to the creation of a web-based registry for adult myositis patients, recently expanded to include paediatrics

Initially European counties (EU and non-EU) expanded to include other collaborators outside Europe (Japan, Mexico, China, US)

▪ Collaborators in formation of a minimal dataset

▪ Representation in NGT meeting

▪ Testing data collection over time (Stage 3, potential)

OMERACT [11]

An independent initiative of international health professionals interested in outcome measures in rheumatology

North America, Europe and Asia-Pacific

▪ Advisory role in development of Delphi survey and in patient involvement

▪ Representation in NGT meeting