Table 4: Revised ACR 1987 criteria for diagnosis of rheumatoid arthritis (RA).

CriterionDefinition

(1) Morning stiffnessMorning stiffness in and around the joints, lasting at least 1 hour before maximal improvement
(2) Arthritis of 3 or more joint areasAt least 3 joint areas simultaneously have had soft tissue swelling or fluid (not bony overgrowth alone) observed by a physician. The 14 possible areas are right or left PIP, MCP, wrist, elbow, knee, ankle, and MTP joints
(3) Arthritis of hand jointsAt least 1 area swollen (as defined above) in a wrist, MCP, or PIP joint
(4) Symmetric arthritisSimultaneous involvement of the same joint areas (as defined in 2) on both sides of the body (bilateral involvement of PIPs, MCPs, or MTPs is acceptable without absolute symmetry)
(5) Rheumatoid nodulesSubcutaneous nodules over bony prominences, extensor surfaces, or juxtaarticular regions, observed by a physician
(6) Serum rheumatoid factorDemonstration of abnormal amounts of serum rheumatoid factor by any method for which the result has been positive in <5% of normal control subjects
(7) Radiographic changesRadiographic changes typical of rheumatoid arthritis on posteroanterior hand and wrist radiographs, which must include erosions or unequivocal bony decalcification localized in or most marked adjacent to the involved joints (osteoarthritis changes alone do not qualify)

Note: criteria 1 through 4 must have been present for at least 6 weeks. Rheumatoid arthritis is defined by the presence of 4 or more criteria, and no further qualifications (classic, definite, or probable) or list of exclusions are required.