2016 American College of Rheumatology/European League Against Rheumatism Criteria for Minimal, Moderate, and Major Clinical Response in Juvenile Dermatomyositis: An International Myositis Assessment and Clinical Studies Group/Paediatric Rheumatology International Trials Organisation Collaborative Initiative

Abstract

Objective Develop response criteria for juvenile dermatomyositis (JDM). Methods We analyzed the performance of 312 definitions that used core set measures (CSM) from either the International Myositis Assessment and Clinical Studies Group (IMACS) or the Pediatric Rheumatology International Trials Organization (PRINTO) and were derived from natural history data and a conjoint-analysis survey. They were further validated in the PRINTO trial of prednisone alone compared to prednisone with methotrexate or cyclosporine and the Rituximab in Myositis trial. Experts considered 14 top-performing candidate criteria based on their performance characteristics and clinical face validity using nominal group technique at a consensus conference. Results Consensus was reached for a conjoint analysis–based continuous model with a Total Improvement Score of 0-100, using absolute percent change in CSM with thresholds for minimal (≥30 points), moderate (≥45), and major improvement (≥70). The same criteria were chosen for adult dermatomyositis/polymyositis with differing thresholds for improvement. The sensitivity and specificity were 89% and 91-98% for minimal, 92-94% and 94-99% for moderate, and 91-98% and 85-85% for major improvement, respectively, in JDM patient cohorts using the IMACS and PRINTO CSM. These criteria were validated in the PRINTO trial for differentiating between treatment arms for minimal and moderate improvement (P=0.009–0.057) and in the Rituximab trial for significantly differentiating the physician rating of improvement (P<0.006). Conclusion The response criteria for JDM was a conjoint analysis–based model using a continuous improvement score based on absolute percent change in CSM, with thresholds for minimal, moderate, and major improvement.

2016 American College of Rheumatology/European League Against Rheumatism Criteria for Minimal, Moderate, and Major Clinical Response in Adult Dermatomyositis and Polymyositis: An International Myositis Assessment and Clinical Studies Group/Paediatric Rheumatology International Trials Organisation Collaborative Initiative

“…Validation. Candidate definitions with a sensitivity and specificity of $80%, AUC $0.9 for minimal, and AUC $0.8 for moderate and major improvement in the patient profile analysis using expert consensus rating as the gold standard were evaluated for external validation using RIM clinical trial data (3) (20) were considered by the adult working group at the consensus conference so that, in total, 18 candidate definitions were evaluated (Table 2 and Supplementary Table 2, available on the Arthritis & Rheumatology web site at http://onlinelibrary.wiley.com/doi/ 10.1002/art.40064/abstract). They included 9 categorical definitions and 9 continuous definitions, in which 14 used relative percent change and 4 used absolute percent change in core set measures.…”

“…§ Conjoint analysis-based continuous candidate response criteria using absolute percent change in core set measures (absolute percent change model) is shown in Table 3. These criteria are also the top response criteria for juvenile dermatomyositis (DM), but with different thresholds in the total improvement score for minimal, moderate, and major improvement (20). ¶ Conjoint analysis-based continuous candidate response criteria using relative percent change in core set measures are shown in Supplementary Table 3 (available on the Arthritis & Rheumatology web site at http://onlinelibrary.wiley.com/doi/10.1002/art.40064/abstract).…”

“…¶ Conjoint analysis-based continuous candidate response criteria using relative percent change in core set measures are shown in Supplementary Table 3 (available on the Arthritis & Rheumatology web site at http://onlinelibrary.wiley.com/doi/10.1002/art.40064/abstract). These criteria are also the second-and third-choice criteria for juvenile DM, but with different thresholds in the total improvement score for minimal, moderate, and major improvement (20). # The total improvement score is calculated as 2 the continuous definitions, however, each subject generates a total improvement score on a continuous scale, such that a greater degree of improvement corresponds to a higher score.…”

Measurement of Respiratory Function Decline in Patients with Duchenne Muscular Dystrophy: A Conjoint Analysis

“…Our conjoint analysis, conducted in Italy, was developed according to a statistical method with mounting importance in medicine [8], and therefore it can be considered robust although it was conducted on the evaluation of computer generated patient profiles and not on actual patients. Similarly, attributes were identified ab initio by experts and we cannot rule out that other attributes (e.g., symptoms of chronic alveolar hypoventilation, proBNP, use of steroids, cough assist machine or noninvasive overnight monitoring of carbon dioxide, overnight SpO 2 and maximum inspiration capacity could have been evaluated) could contribute to a closer definition of severity of respiratory symptoms.…”

“…Noteworthy, this approach has been recently used in the rheumatology field to stratify clinical response to treatment in patients with juvenile dermatomyositis [8]. Given its characteristics, conjoint analysis can be a valuable tool for the stratification of risk of pulmonary decline and respiratory complications in DMD patients.…”