Under the old diagnostic criteria for rheumatoid arthritis, how many of the seven features were required and for how long?

• A. 4 of 7 over 6 weeks
• B. 3 of 7 over 3 weeks
• C. 5 of 7 over 8 weeks
• D. 6 of 7 over 4 weeks

Answer: (A)

The old rheumatoid arthritis criteria were defined so that a diagnosis required persistent inflammatory features rather than short-lived joint pain. Specifically, four of seven characteristic features had to be present for at least six weeks. The seven features are: morning stiffness lasting more than an hour, arthritis in three or more joints, involvement of hand joints (wrist, MCP, or PIP), symmetric arthritis, rheumatoid nodules, serum rheumatoid factor positivity, and radiographic changes typical of RA. The six-week duration helps distinguish chronic inflammatory arthritis from transient or noninflammatory conditions. These criteria guided diagnosis for many years but were later updated to allow earlier classification with a scoring system in 2010.