RA disease activity indices: calculation and values for disease activity states*
| RA activity state | |||||
|---|---|---|---|---|---|
| Index | Formula | Remission | Low | Moderate | High |
| DAS28 | 0.56*√(TJC28)+0.28*√(SJC28)+0.70*ln(ESR)+0.014*GH | <2.6 | 2.6 to ≤3.2 | >3.2 to ≤5.1 | >5.1 |
| CDAI | TJC28+SJC28+MDGL+PTGL | <2.8 | 2.8 to ≤10 | > 10 to ≤22 | >22 |
| RAPID3† | HAQ+Pain+PTGL | <3 | 3 to ≤6 | > 6 to ≤12 | >12 |
↵* PTGL or GH rating was scored on 0–10 scale for CDAI and RAPID3, and 0–100 scale for DAS28.
↵† HAQ scored on a 0–10 scale for purpose of computing RAPID3 score.
CDAI, Clinical Disease Activity Index; DAS28, Disease Activity Score based on 28 joint evaluation; ESR, erythrocyte sedimentation rate; GH, patient's assessment of general health; HAQ, health assessment questionnaire; MDGL, physician's global assessment of disease activity; PTGL, patient's global assessment of disease activity; RA, rheumatoid arthritis; RAPID3, Routine Assessment of Patient Index Data 3; SJC28, swollen joint count on 28 joint evaluation; TJC28, tender joint count on 28 joint evaluation.