Funding for this research was provided by:
FP7 People: Marie-Curie Actions (289903)
The Myositis Association
Wellcome Trust (085860)
Action Medical Research (SP4252)
The Myositis Support Group UK
Arthritis Research UK (14518, 20164)
The Henry Smith Charity and Great Ormond Street Children's Charity (V1268)
Medical Research Council
National Institute for Health Research (NIHR) Translational Research Collaboration (TRC) Rare Diseases
NIHR Great Ormond Street Hospital for Children NHS Foundation Trust Biomedical Research Centre (NIHR-GOSH BRC)
Received: 16 February 2018
Accepted: 25 July 2018
First Online: 15 August 2018
Ethics approval and consent to participate
: Ethical approval was obtained by the multicenter ethical review board covering all participating institutions. All participants provided written informed consent, or age-appropriate assent with parental consent.
: Not applicable.
: The authors declare that they have no competing interests.
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