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Your Environment. Your Health.

Validation of IMACS and PRINTO Definitions of Improvement

Principal Investigator:

Lisa Rider, NIEHS, NIH

Study Design:

Natural history study

Types & Number of IIM Studied:

Adult and Juvenile Dermatomyositis, Polymyositis, Overlap Myositis, Inclusion Body Myositis (> 100 patients)

Entry Criteria:

Probable or definite Bohan and Peter criteria; Griggs et al. 1995 Annals of Neurology Inclusion Body Myositis criteria

IMACS Core Set Measures Included:

All: Physician and Patient Global Activity and Damage Assessments, Manual Muscle Testing, Childhood Myositis Assessment Scale, [Childhood] Health Assessment Questionnaire, muscle enzymes, Myositis Disease Activity Assessment Tool, Myositis Damage Index; Health Related Quality of Life by SF-36 and Child Health Questionnaire

Other Measures Included:

Disease Activity Score, demographic and treatment data, extended measures

Primary Outcome:

IMACS and PRINTO Definitions of Improvement

Study Duration:

Baseline and 6 - 9 month evaluation. Open




Ongoing. Extramural centers may apply for enrollment into IMACS registry by obtaining local IRB approval of this protocol.


Lisa Rider, M.D.
Deputy Chief and Senior Research Physician, Environmental Autoimmunity Group
Frederick W. Miller, M.D., Ph.D.
Deputy Chief, Clinical Research Branch and Principal Investigator
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