Objective The 1987 American College of Rheumatology (ACR; formerly the American Rheumatism Association) classification criteria for rheumatoid arthritis (RA) have been criticised for their lack of... Show moreObjective The 1987 American College of Rheumatology (ACR; formerly the American Rheumatism Association) classification criteria for rheumatoid arthritis (RA) have been criticised for their lack of sensitivity in early disease. This work was undertaken to develop new classification criteria for RA. Methods A joint working group from the ACR and the European League Against Rheumatism developed, in three phases, a new approach to classifying RA. The work focused on identifying, among patients newly presenting with undifferentiated inflammatory synovitis, factors that best discriminated between those who were and those who were not at high risk for persistent and/or erosive disease-this being the appropriate current paradigm underlying the disease construct 'RA'. Results In the new criteria set, classification as 'definite RA' is based on the confirmed presence of synovitis in at least one joint, absence of an alternative diagnosis better explaining the synovitis, and achievement of a total score of 6 or greater (of a possible 10) from the individual scores in four domains: number and site of involved joints (range 0-5), serological abnormality (range 0-3), elevated acute-phase response (range 0-1) and symptom duration (two levels; range 0-1). Conclusion This new classification system redefines the current paradigm of RA by focusing on features at earlier stages of disease that are associated with persistent and/or erosive disease, rather than defining the disease by its late-stage features. This will refocus attention on the important need for earlier diagnosis and institution of effective disease-suppressing therapy to prevent or minimise the occurrence of the undesirable sequelae that currently comprise the paradigm underlying the disease construct 'RA'. Show less
Objective. The American College of Rheumatology and the European League Against Rheumatism have developed new classification criteria for rheumatoid arthritis (RA). The aim of Phase 2 of the... Show moreObjective. The American College of Rheumatology and the European League Against Rheumatism have developed new classification criteria for rheumatoid arthritis (RA). The aim of Phase 2 of the development process was to achieve expert consensus on the clinical and laboratory variables that should contribute to the final criteria set. Methods. Twenty-four expert RA clinicians (12 from Europe and 12 from North America) participated in Phase 2. A consensus-based decision analysis approach was used to identify factors (and their relative weights) that influence the probability of "developing RA," complemented by data from the Phase 1 study. Patient case scenarios were used to identify and reach consensus on factors important in determining the probability of RA development. Decision analytic software was used to derive the relative weights for each of the factors and their categories, using choice-based conjoint analysis. Results. The expert panel agreed that the new classification criteria should be applied to individuals with undifferentiated inflammatory arthritis in whom at least 1 joint is deemed by an expert assessor to be swollen, indicating definite synovitis. In this clinical setting, they identified 4 additional criteria as being important: number of joints involved and site of involvement, serologic abnormality, acute-phase response, and duration of symptoms in the involved joints. These criteria were consistent with those identified in the Phase 1 data-driven approach. Conclusion. The consensus-based, decision analysis approach used in Phase 2 complemented the Phase 1 efforts. The 4 criteria and their relative weights form the basis of the final criteria set. Show less
Funovits, J.; Aletaha, D.; Bykerk, V.; Combe, B.; Dougados, M.; Emery, P.; ... ; Silman, A. 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... Show moreObjective 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. Show less
Objective. The 1987 American College of Rheumatology (ACR; formerly, the American Rheumatism Association) classification criteria for rheumatoid arthritis (RA) have been criticized for their lack... Show moreObjective. The 1987 American College of Rheumatology (ACR; formerly, the American Rheumatism Association) classification criteria for rheumatoid arthritis (RA) have been criticized for their lack of sensitivity in early disease. This work was undertaken to develop new classification criteria for RA. Methods. A joint working group from the ACR and the European League Against Rheumatism developed, in 3 phases, a new approach to classifying RA. The work focused on identifying, among patients newly presenting with undifferentiated inflammatory synovitis, factors that best discriminated between those who were and those who were not at high risk for persistent and/or erosive disease-this being the appropriate current paradigm underlying the disease construct "rheumatoid arthritis." Results. In the new criteria set, classification as "definite RA" is based on the confirmed presence of synovitis in at least 1 joint, absence of an alternative diagnosis that better explains the synovitis, and achievement of a total score of 6 or greater (of a possible 10) from the individual scores in 4 domains: number and site of involved joints (score range 0-5), serologic abnormality (score range 0-3), elevated acute-phase response (score range 0-1), and symptom duration (2 levels; range 0-1). Conclusion. This new classification system redefines the current paradigm of RA by focusing on features at earlier stages of disease that are associated with persistent and/or erosive disease, rather than defining the disease by its late-stage features. This will refocus attention on the important need for earlier diagnosis and institution of effective disease-suppressing therapy to prevent or minimize the occurrence of the undesirable sequelae that currently comprise the paradigm underlying the disease construct "rheumatoid arthritis." Show less
