The value of the diagnostic criteria in rheumatoid arthritis.

The ARA and the New York diagnostic criteria for rheumatoid arthritis were studied in 411 patients with a recent inflammatory joint disease (100 with RA, 311 with other disease) in order to evaluate their value in distinguishing progressive rheumatoid arthritis from other joint diseases. Rheumatoid factor, symmetrical polyarthritis, morning stiffness, and X-ray changes were of the greatest value in diagnosing RA in the early stage of the disease. Other diagnostic criteria had either a poor specificity or sensitivity, and were thus of less importance as discriminators.