TABLE 2.

Comparison of proposed sets of measures for disease activity in juvenile dermatomyositis, from two international collaborative efforts.

	IMACS	PRINTO
Target population	All IIM, including JDM	JDM
Domain
Physician assessment	Physician global assessment of disease activity by visual analogue scale (VAS) or Likert scale	Physician global assessment of disease activity by visual analogue scale (VAS) or Likert scale
Patient/parent assessment	Patient/parent global assessment of disease activity using by visual analogue scale (VAS) or Likert scale	Patient/parent global assessment of overall well being using by visual analogue scale (VAS) or Likert scale
Muscle strength	MMT	MMT, CMAS
Functional ability	CHAQ or CMAS	CHAQ
Laboratory measurement	At least two of CK, LDH, aldolase, ALT, AST	Not included in the final core set, but recommended to be reported: CK, LDH, aldolase, ALT, AST
Global disease activity tool	Not included	DAS or MDAAT
Extra-muscular disease	MDAAT	Not included
Health-related QOL	Not included; measured separately	CHQ Physical Summary score

PRINTO, Paediatric Rheumatology Inte International Myositis Assessment and Clinical Studies Group; IIM idiopathic inflammatory myopathies; JDM, juvenile dermatomyositis; VAS, visual analogue scale; Prnational Trials Organisation; IMACS, MMT, manual muscle testing; CMAS, Childhood Myositis Assessment Scale; CHAQ, Childhood Health Assessment Questionnaire; CK, creatine kinase; LDH, lactate dehydrogenase; ALT, alanine aminotransferase AST, aspartate aminotransferase; DAS, Disease Activity Score; MDAAT, Myositis Disease Activity Assessment Tool, which combines the MYOACT (Myositis extra-skeletal muscle disease activity assessment by VAS) and the MITAX (Myositis intention to treat activity index) tools; QOL, quality of life; CHQ, Child Health Questionnaire. Modified from references 58-62.