The provisional Paediatric Rheumatology International Trials Organisation/American College of Rheumatology/european League Against Rheumatism Disease activity core set for the evaluation of response to therapy in juvenile dermatomyositis: A prospective validation study

Authors


  • The American College of Rheumatology is an independent, professional, medical, and scientific society, which does not guarantee, warrant, or endorse any commercial product or service.

  • This core set has been approved by the American College of Rheumatology (ACR) Board of Directors as Provisional. This signifies that the core set has been quantitatively validated using patient data, but it has not undergone validation based on an external data set. All ACR-approved core sets are expected to undergo intermittent updates.

Abstract

Objective

To validate a core set of outcome measures for the evaluation of response to treatment in patients with juvenile dermatomyositis (DM).

Methods

In 2001, a preliminary consensus-derived core set for evaluating response to therapy in juvenile DM was established. In the present study, the core set was validated through an evidence-based, large-scale data collection that led to the enrollment of 294 patients from 36 countries. Consecutive patients with active disease were assessed at baseline and after 6 months. The validation procedures included assessment of feasibility, responsiveness, discriminant and construct ability, concordance in the evaluation of response to therapy between physicians and parents, redundancy, internal consistency, and ability to predict a therapeutic response.

Results

The following clinical measures were found to be feasible, and to have good construct validity, discriminative ability, and internal consistency; furthermore, they were not redundant, proved responsive to clinically important changes in disease activity, and were associated strongly with treatment outcome and thus were included in the final core set: 1) physician's global assessment of disease activity, 2) muscle strength, 3) global disease activity measure, 4) parent's global assessment of patient's well-being, 5) functional ability, and 6) health-related quality of life.

Conclusion

The members of the Paediatric Rheumatology International Trials Organisation, with the endorsement of the American College of Rheumatology and the European League Against Rheumatism, propose a core set of criteria for the evaluation of response to therapy that is scientifically and clinically relevant and statistically validated. The core set will help standardize the conduct and reporting of clinical trials and assist practitioners in deciding whether a child with juvenile DM has responded adequately to therapy.

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