The 2010 American College of Rheumatology/European League Against Rheumatism classification criteria for rheumatoid arthritis: Methodological Report Phase I
- Julia Funovits1,
- Daniel Aletaha1,
- Vivian Bykerk2,
- Bernard Combe3,
- Maxime Dougados4,
- Paul Emery5,
- David Felson6,
- Gillian Hawker7,
- Joanna M Hazes8,
- Tom Huizinga9,
- Jonathan Kay10,
- Tore K Kvien11,
- Josef S Smolen1,12,
- Deborah Symmons13,
- Paul P Tak14,
- Alan Silman15
- 1Division of Rheumatology, Medical University Vienna, Vienna, Austria
- 2Mount Sinai Hospital, Toronto, Canada
- 3CHU de Montpellier, CHU Lapeyronie, Montpellier, France
- 4Paris-Descartes University, Paris, France
- 5University of Leeds and NIHR Leeds Muscoskeletal Biomedical Research Unit, Leeds, UK
- 6Boston University School of Medicine, Boston, Massachusetts, USA
- 7Women's College Hospital, Toronto, Canada
- 8Department of Rheumatology, University Medical Centre Rotterdam, Rotterdam, The Netherlands
- 9Leiden University Medical Centre, Leiden, The Netherlands
- 10UMass Memorial Center, Worcester, Massachusetts, USA
- 11Diakonhjemmet Hospital, Oslo, Norway
- 12Department of Internal Medicine III, Hietzing Hospital, Vienna, Austria
- 13University of Manchester, Manchester, UK
- 14University of Amsterdam, Amsterdam, The Netherlands
- 15Arthritis Research Campaign, Chesterfield, UK
- Correspondence to Daniel Aletaha, Division of Rheumatology, Medical University Vienna, Waehringer Guertel 18-20, Vienna A-1090, Austria;
- Accepted 30 March 2010
Objective To apply a data-driven approach to investigate, in patients newly presenting with undifferentiated inflammatory synovitis, key variables that discriminate the subset of patients at sufficiently high risk of persistent or erosive disease for the purpose of developing new criteria for rheumatoid arthritis (RA).
Methods In this first phase of the collaborative effort of the American College of Rheumatology and European League Against Rheumatism to develop new criteria for RA, a pooled analysis of early arthritis cohorts made available by the respective investigators is presented. All the variables associated with the gold standard of treatment with methotrexate during the first year after enrolment were first identified. Principal component analysis was then used to identify among the significant variables those sets that represent similar domains. In a final step, from each domain one representative variable was extracted, all of which were then tested for their independent effects in a multivariate regression model. From the OR in that final model, the relative weight of each variable was estimated.
Results The final domains and variables identified by this process (and their relative weights) were: swelling of a metacarpophalangeal joint (MCP; 1.5), swelling of a proximal interphalangeal joint (PIP; 1.5), swelling of the wrist (1.5), tenderness of the hand (ie, MCP, PIP or wrist (2)), acute phase reaction (ie, C reactive protein or erythrocyte sedimentation rate and weights for moderate or high elevations of either one (1 for moderate, 2 for high elevation)) and serological abnormalities (ie, rheumatoid factors or anti-citrullinated protein antibodies, again with separate weights for moderate or high elevations (2 and 4, respectively)).
Conclusion The results of this first phase were subsequently used in the second phase of the project, which is reported in a separate methodological paper, and for derivation of the final set of criteria.
Funding ACR, EULAR.
Competing interests None. Francis Berenbaum was the handling editor for this manuscript.
Provenance and peer review Not commissioned; externally peer reviewed.