[Evaluation of the 1987 revised ARA criteria for rheumatoid arthritis in Japan]

Three hundred and sixty two Japanese patients with rheumatoid arthritis (RA) and 455 patients with other rheumatic diseases (SLE 233, PSS 63, MCTD 51, PM-DM 41 Behcet's disease 33 and OA 33) were examined for the evaluation of the 1987 revised ARA criteria for RA. In our cases sensitivity was slightly decreased and specificity was markedly increased 5 out of 7 criterions compared with the results reported by ARA. In the investigation how many number of criterions at least which the patients with RA should satisfy, 4 out of 7 criterions in the 1987 criteria turned out the highest figure in the accuracy (the mean of sensitivity and specificity values). So the patients who satisfied at least 4 criterions were classified to have RA. Sensitivity of the 1987 criteria decreased to 90% although that of the 1958 ARA criteria was 93%. Specificity were markedly increased from 88% to 95% (the 1958 and 1987 criteria, respectively). These results might be based on the revision of the duration of "morning stiffness" (lasting at least 1 hour) and on the deletion of "joint pain or tenderness" which was relatively less specific for RA.