Skip Navigation

Your Environment. Your Health.

Myositis Response Criteria

IMACS and PRINTO, the Pediatric International Trials Organisation, have partnered with an international group of myositis experts to develop standardized clinical response criteria to assess minimal, moderate and major clinical improvement in patients with adult dermatomyositis and juvenile dermatomyositis.  These criteria, which have now been accepted by the American College of Rheumatology and European League Against Rheumatism, are recommended for use as primary endpoints in myositis therapeutic trials.  The criteria use the 6 IMACS or 6 PRINTO core set measures, combining the absolute percentage change in each with varying weights to obtain a Total Improvement Score on a scale of 0-100. Different thresholds of improvement have been set for minimal, moderate and major response, and these response thresholds also differ between adult and pediatric patients. The criteria may be used as a continuous outcome measure, using the Total Improvement Score, or as a categorical outcome of improvement (minimal, moderate or major improvement) and thus are a hybrid measure.

Final 2016 ACR/EULAR Criteria for Minimal, Moderate, and Major Clinical Response in Adult Dermatomyositis and Polymyositis and Juvenile Dermatomyositis

 

Web Calculators to Calculate the New Response Criteria

Two separate online calculators for the 2016 ACR/EULAR Myositis Response Criteria are available - one for adult dermatomyositis/polymyositis and one for juvenile dermatomyositis, allowing for easy, practical use of the response criteria.  These calculators require inputting of baseline and follow-up values for all 6 core set activity measures.  The maximum potential manual muscle testing score and the upper limit of the serum muscle enzymes must also be inputted; enzymes are expressed in Unit/L or microkat/L. For the pediatric calculator, the IMACS or PRINTO measures may be used. At minimum, the calculator requires input of the Physician Global Activity, Manual Muscle Testing (or Childhood Myositis Assessment Scale) and at least 2 other core set measures to provide a calculation of response. The Total Improvement Score will also be obtained.

To download the calculators for offline use, please right click the calculator link and select the option to "Save Link (or Target) As..."

Publications of the Response Criteria

  • Aggarwal R, Rider LG, Ruperto N, Bayat N, Erman B, Feldman BM, Oddis CV, Amato AA, Chinoy H, Cooper RG, Dastmalchi M, Fiorentino D, Isenberg D, Katz JD, Mammen A, de Visser M, Ytterberg SR, Lundberg IE, Chung L, Danko K, García-De la Torre I, Song YW, Villa L, Rinaldi M, Rockette H, Lachenbruch PA, Miller FW, Vencovsky J; International Myositis Assessment and Clinical Studies Group and the Paediatric Rheumatology International Trials Organisation. 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. Arthritis Rheumatol. 2017 May;69(5):898-910. doi: 10.1002/art.40064. [Abstract]
  • Rider LG, Aggarwal R, Pistorio A, Bayat N, Erman B, Feldman BM, Huber AM, Cimaz R, Cuttica RJ, de Oliveira SK, Lindsley CB, Pilkington CA, Punaro M, Ravelli A, Reed AM, Rouster-Stevens K, van Royen-Kerkhof A, Dressler F, Magalhaes CS, Constantin T, Davidson JE, Magnusson B, Russo R, Villa L, Rinaldi M, Rockette H, Lachenbruch PA, Miller FW, Vencovsky J, Ruperto N; International Myositis Assessment and Clinical Studies Group and the Paediatric Rheumatology International Trials Organisation. 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. Arthritis Rheumatol. 2017 May;69(5):911-923. doi: 10.1002/art.40060. [Abstract] 
  • Rider LG, Aggarwal R, Pistorio A, Bayat N, Erman B, Feldman BM, Huber AM, Cimaz R, Cuttica RJ, de Oliveira SK, Lindsley CB, Pilkington CA, Punaro M, Ravelli A, Reed AM, Rouster-Stevens K, van Royen-Kerkhof A, Dressler F, Saad Magalhaes C, Constantin T, Davidson JE, Magnusson B, Russo R, Villa L, Rinaldi M, Rockette H, Lachenbruch PA, Miller FW, Vencovsky J, Ruperto N; International Myositis Assessment and Clinical Studies Group and the Paediatric Rheumatology International Trials Organisation. 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. Ann Rheum Dis. 2017 May;76(5):782-791. doi: 10.1136/annrheumdis-2017-211401. [Abstract] 
  • Rider LG, Aggarwal R, Pistorio A, Bayat N, Erman B, Feldman BM, Huber AM, Cimaz R, Cuttica RJ, de Oliveira SK, Lindsley CB, Pilkington CA, Punaro M, Ravelli A, Reed AM, Rouster-Stevens K, van Royen-Kerkhof A, Dressler F, Saad Magalhaes C, Constantin T, Davidson JE, Magnusson B, Russo R, Villa L, Rinaldi M, Rockette H, Lachenbruch PA, Miller FW, Vencovsky J, Ruperto N; International Myositis Assessment and Clinical Studies Group and the Paediatric Rheumatology International Trials Organisation. 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. Ann Rheum Dis. 2017 May;76(5):782-791. doi: 10.1136/annrheumdis-2017-211401. [Abstract] 
  • Rider LG, Ruperto N, Pistorio A, Erman B, Bayat N, Lachenbruch PA, Rockette H, Feldman BM, Huber AM, Hansen P, Oddis CV, Lundberg IE, Amato AA, Chinoy H, Cooper RG, Chung L, Danko K, Fiorentino D, García-De la Torre I, Reed AM, Wook Song Y, Cimaz R, Cuttica RJ, Pilkington CA, Martini A, van der Net J, Maillard S, Miller FW, Vencovsky J, Aggarwal R; International myositis Assessment and Clinical Studies Group and the Paediatric Rheumatology International Trials Organisation. 2016 ACR-EULAR adult dermatomyositis and polymyositis and juvenile dermatomyositis response criteria-methodological aspects. Rheumatology (Oxford). 2017 Nov 1;56(11):1884-1893. doi: 10.1093/rheumatology/kex226. PubMed PMID: 28977549. [Abstract] 

Endorsement of these Criteria by the American College of Rheumatology and European League Against Rheumatism

Background on the New Response Criteria

Programs for the New Response Criteria

Available soon.

Web-based Data Repository

Available soon

IMACS Assessment of Study Outcomes

Description: This form assesses the degree of improvement or worsening in subjects enrolled clinical trials or natural history studies that will be used towards validating the new response criteria. Assessments are completed by the enrolling physician.

MD Assessment of Study Outcomes(30KB) 

Definitions of Improvement

IMACS and PRINTO have previously developed and partially validated Preliminary Definitions of Improvement for Adult and Juvenile Myositis and Provisional Criteria for Response to Therapy, respectively, which combine core set measures of disease activity and define a minimal degree of clinically meaningful change in each of the core set activity measures. These criteria were published and previously used as endpoints in myositis therapeutic trials. The PRINTO provisional response criteria, with the addition of new thresholds for moderate and major improvement, has been accepted among the top 5 candidate criteria for juvenile dermatomyositis to include as a secondary endpoint in clinical trials.  These criteria/definitions of improvement are otherwise no longer recommended for use.

  • Rider LG, Giannini EH, Brunner HI, Ruperto N, James-Newton L, Reed AM, Lachenbruch PA, Miller FW; International consensus on preliminary definitions of improvement in adult and juvenile myositis. International Myositis Assessment and Clinical Studies Group. Arthritis Rheum. 2004 Jul;50(7):2281-90. PubMed PMID: 15248228. [Abstract] 
  • Ruperto N, Pistorio A, Ravelli A, Rider LG, Pilkington C, Oliveira S, Wulffraat N, Espada G, Garay S, Cuttica R, Hofer M, Quartier P, Melo-Gomes J, Reed AM, Wierzbowska M, Feldman BM, Harjacek M, Huppertz HI, Nielsen S, Flato B, Lahdenne P, Michels H, Murray KJ, Punaro L, Rennebohm R, Russo R, Balogh Z, Rooney M, Pachman LM, Wallace C, Hashkes P, Lovell DJ, Giannini EH, Gare BA, Martini A; The Paediatric Rheumatology International Trials Organisation provisional criteria for the evaluation of response to therapy in juvenile dermatomyositis. Paediatric Rheumatology International Trials Organisation (PRINTO); Pediatric Rheumatology Collaborative Study Group (PRCSG). Arthritis Care Res (Hoboken). 2010 Nov;62(11):1533-41. doi: 10.1002/acr.20280. Epub 10 Jun 25. PubMed PMID: 20583105; PubMed Central PMCID: PMC2964396. [Abstract]