Table 1.

Overarching principles for juvenile dermatomyositis (JDM)

	L	S	Agreement (%)
All children with suspected idiopathic inflammatory myopathies should be referred to a specialised centre.	4	D	100
High-risk patients need immediate/urgent referral to a specialised centre. High risk patients are defined by Severe disability, defined by inability to get off bed CMAS score <15, or MMT8 score <30 Presence of aspiration or dysphagia (to the point of inability to swallow) Gastrointestinal vasculitis (as determined by imaging or presence of bloody stools) Myocarditis Parenchymal lung disease Central nervous system disease (defined as decreased level of consciousness or seizures) Skin ulceration Requirement for intensive care unit management Age <1 year	4	D	100
For JDM, patient-/parent-reported outcome measures are helpful when assessing disease activity and should be used at diagnosis and during disease monitoring.	4	D	100
Validated tools should be used to measure health status, for example, the Childhood Health Assessment Questionnaire, patient/parent visual analogue scale, Childhood Health Questionnaire, Juvenile Dermatomyositis Multi-dimensional Assessment Report.	4	D	82
All children with JDM should have disease activity (muscle, skin, major organ) assessed regularly in a standardised way, using tools such as the Disease Activity Score.	4	D	100
All children with JDM should have disease damage assessed at least yearly using a standardised disease damage measure, such as the Myositis Damage Index.	4	D	100
All patients with JDM should have the opportunity to be registered within a research registry/repository, for example, the Euromyositis registry.	4	D	100

Agreement indicates percentage of experts that agreed on the recommendation during the final voting round of the consensus meeting.

1A, meta-analysis of randomised controlled trial; 1B, randomised controlled study; 2A, controlled study without randomisation; 2B, quasi-experimental study; 3, descriptive study; 4 expert opinion; A, based on level 1 evidence; B, based on level 2 or extrapolated from level 1; C, based on level 3 or extrapolated from level 1 or 2; CMAS, Childhood Myositis Assessment Scale; D, based on level 4 or extrapolated from level 3 or 4 expert opinion; L, level of evidence; MMT, Manual Muscle Test; S, strength of recommendation;