Table 2. Summary of tools available for the assessment of skin disease in the IIM*.

Name	Abbreviation	Global Tool or Independent Skin Assessment	Subgroup validated	Validation
Disease Activity Score	DAS	Part of Global Tool	JDM	Reliability, Construct validity, Responsiveness
Myositis Disease Activity Assessment	MYOACT	Part of Global Tool	JDM, DM, PM	Responsivene
Myositis Intention-to-Treat Activity Index	MITAX	Part of Global Tool	JDM, DM, PM	Responsiveness
Cutaneous Assessment Tool	CAT	Independent Skin Assessment	JDM	Reliability, Construct Validity, Responsiveness
Dermatomyositis Skin Severity Index	DSSI	Independent Skin Assessment	JDM, DM	Reliability, Construct Validity
Cutaneous Dermatomyositis Disease Area and Severity Index	CDASI	Independent Skin Assessment	DM, ADM	Reliability, Construct Validity

* Abbreviations:

IIM = idiopathic inflammatory myopathies
JDM = juvenile dermatomyositis
DAS = Disease Activity Score
MYOACT = Myositis Disease Activity Assessment Tool, Visual Analog Scale version
MITAX = Myositis Intention-to-Treat Activity Index
CAT = Cutaneous Assessment Tool
DSSI = Dermatomyositis Skin Severity Index
CDASI = Cutaneous Dermatomyositis Disease Area and Severity Index
DM = dermatomyositis
PM = polymyositis
ADM = amyopathic dermatomyositis