Univariate and multivariate logistic regressions to estimate associations among 4 indices (SDAI, CDAI, RAPID3, and DAS28) to predict remission status at both 6- and 12-month timepoints. All univariate logistic regression results to predict SDAI or CDAI remission are p < 0.001 except for RAPID3, which is p < 0.01. All multivariate logistic regression results are p < 0.001 except the Boolean criteria to predict SDAI, CDAI, DAS28, and RAPID3, which are p = 0.18, p = 0.52, p = 0.75, and p = 0.02, respectively.
| Baseline Variables | Boolean Criteria, n = 165 (24.8%) OR (95% CI) | SDAI ≤ 3.3, n = 204 (30.8%) OR (95% CI) | CDAI ≤ 2.8, n = 205 (30.9%) OR (95% CI) | DAS28 ≤ 2.6, n = 339 (51.4%) OR (95% CI) | RAPID3 ≤ 3, n = 273 (41.1%) OR (95% CI) | RAPID3 ≤ 3 + SJ ≤ 1, n = 209 (31.5%) OR (95% CI) |
|---|---|---|---|---|---|---|
| Univariate logistic regression | ||||||
| SDAI | 0.81 (0.77–0.84) | 0.96 (0.95–0.97) | 0.96 (0.95–0.97) | 0.97 (0.96–0.98) | 0.98 (0.97–1.00) | 0.97 (0.96–0.99) |
| CDAI | 0.80 (0.77–0.84) | 0.95 (0.94–0.97) | 0.95 (0.94–0.97) | 0.97 (0.95–0.98) | 0.98 (0.97–0.99) | 0.97 (0.96–0.98) |
| DAS28 | 0.32 (0.26–0.40) | 0.68 (0.59–0.78) | 0.69 (0.60–0.79) | 0.64 (0.56–0.73) | 0.81 (0.71–0.92) | 0.75 (0.65–0.85) |
| RAPID3 | 0.76 (0.72–0.80) | 0.92 (0.89–0.95) | 0.92 (0.89–0.95) | 0.91 (0.89–0.94) | 0.90 (0.87–0.93) | 0.92 (0.89–0.95) |
| Multivariate logistic regression | ||||||
| SDAI | 0.91 (0.69–1.20) | 1.01 (0.96–1.07) | 1.03 (0.97–1.09) | 1.09 (1.03–1.16) | 1.05 (0.99–1.11) | 1.05 (1.00–1.11) |
| CDAI | 0.96 (0.72–1.26) | 0.95 (0.90–1.00) | 0.93 (0.88–0.98) | 0.93 (0.88–0.99) | 0.97 (0.92–1.02) | 0.94 (0.90–1.00) |
| DAS28 | 0.78 (0.55–1.12) | 1.05 (0.78–1.41) | 1.07 (0.79–1.44) | 0.55 (0.41–0.73) | 1.00 (0.76–1.33) | 0.89 (0.66–1.20) |
| RAPID3 | 0.91 (0.85–0.99) | 0.97 (0.93–1.01) | 0.97 (0.93–1.01) | 0.96 (0.92–0.99) | 0.87 (0.84–0.91) | 0.94 (0.90–0.98) |
SDAI: Simplified Disease Activity Index; CDAI: Clinical Disease Activity Index; RAPID3: Routine Assessment of Patient Index Data 3; DAS28: Disease Activity Score at 28 joints; SJ: swollen joint.