Physician consensus and case analysis help establish new RA criteria

October 27, 2010

American College of Rheumatology and European League Against Rheumatism investigators who developed new classification criteria for rheumatoid arthritis (RA) used a consensus-based, decision analysis approach during phase 2 that included evaluation of case scenarios to identify predictive factors for persistent inflammatory or erosive arthritis.

American College of Rheumatology and European League Against Rheumatism investigators who developed new classification criteria for rheumatoid arthritis (RA) used a consensus-based, decision analysis approach during phase 2 that included evaluation of case scenarios to identify predictive factors for persistent inflammatory or erosive arthritis. This approach was informed by and complemented their phase 1 efforts.

In phase 1, Aletaha and associates used cohort data to identify key factors to include in the new criteria and their relative importance. Phase 2 included the following 4 steps: assembly of an expert panel, development and rank ordering of patient case scenarios, a 2-day in-person consensus meeting, and assessment of face and construct validity.

The team identified 6 criteria that foretell of erosive arthritis in persons who have early synovitis. Two-synovitis in at least 1 joint and absence of another condition to explain it-are essential for defining RA. The other 4 criteria were key but of differing importance. The duration of morning stiffness was unimportant because it is nondiscriminatory.

The authors noted that their work in the first 2 phases informed a third phase, in which the final criteria set, including the cut point to be used to define definite RA, was determined.