RAPID3 (Routine Assessment of Patient Index Data 3), a rheumatoid arthritis index without formal joint counts for routine care: proposed severity categories compared to disease activity score and clinical disease activity index categories

, and time to score. Methods. Four rheumatologists each assessed 50 patients with rheumatoid arthritis in "real-time" clinical care. Patients completed an MDHAQ. The rheumatologist then calculated RAPID3 (physical function, pain, patient global estimate), performed a 28-joint count, assigned a physician global estimate, and scored a CDAI, each timed by an observer. Erythrocyte sedimentation rate (ESR) was tested on the same date, and the DAS28-ESR was computed later, again timed by an observer. Spearman's rank-order correlations and comparisons of patients classified as high activity, moderate activity, low activity, and remission according to the DAS28, CDAI, and RAPID3 were computed and compared with kappa statistics. A second study of 25 "paper patients" was also performed to compare time to score the DAS28, CDAI, and RAPID3 on a 0 -10 versus 0 -30 scale. Mean and median times to score each index were computed. Results. The 3 indices were correlated significantly, including agreement for >80% of patients for high/moderate activity. The mean time to perform a 28-joint count was 94 seconds, and the mean times to score the DAS28, CDAI, RAPID3 on a 0 -10 scale, and RAPID3 on a 0 -30 scale were 114, 106, 9.6, and 4.6 seconds, respectively. Conclusion. RAPID3 scores provide similar quantitative information to DAS28 and CDAI, while calculated on a 0 -30 scale in about 5% of the time