Table 2.
Multivariable logistic regressiona
| Model Characteristics | Derivation | Validation | ||
|---|---|---|---|---|
| OR > 1.5 or OR < 0.67 | Stepwise, AIC/BICb | OR > 1.5 or OR < 0.67 | Stepwise, AIC/BICb | |
| AUROC (95% CI) | 0.739 (0.679‐0.800) | 0.728 (0.666‐0.790) | 0.756 (0.689‐0.824) | 0.731 (0.657‐0.806) |
| AUROC (10‐fold cross‐validation) (95% CI) | 0.656 (0.588‐0.725) | 0.669 (0.600‐0.737) | 0.632 (0.549‐0.716) | 0.639 (0.552‐0.727) |
| AIC | 407.046 | 401.738 | 288.281 | 283.436 |
| BIC | 473.591 | 447.488 | 351.330 | 326.777 |
| Calibration slope | 0.995 | 0.996 | 0.971 | 1.023 |
| Predictors Included | P and OR (95% CI) | P and OR (95% CI) | P and OR (95% CI) | P and OR (95% CI) |
|---|---|---|---|---|
| Age (OR per 1‐y increase) | 0.1506 | 0.1135 | 0.1688 | 0.1424 |
| 0.98 (0.96‐1.01) | 0.98 (0.96‐1.00) | 0.98 (0.95‐1.01) | 0.98 (0.96‐1.01) | |
| Baseline CDAI (OR per 1‐U increase) | 0.1916 | 0.2277 | 0.0490 | 0.0919 |
| 0.98 (0.96‐1.01) | 0.99 (0.96‐1.01) | 0.97 (0.94‐1.00) | 0.97 (0.95‐1.00) | |
| Disease duration (OR per 12‐mo increase) | 0.4009 | … | 0.8205 | … |
| 0.97 (0.91‐1.04) | … | 0.99 (0.94‐1.05) | … | |
| Sex | 0.6441 | 0.6884 | 0.5047 | 0.5748 |
| Female | Reference | Reference | Reference | Reference |
| Male | 1.16 (0.62‐2.17) | 1.13 (0.61‐2.09) | 1.32 (0.58‐3.01) | 1.26 (0.57‐2.78) |
| Region | 0.0159 | 0.0137 | 0.0043 | 0.0064 |
| Europe | 2.33 (1.03‐5.27) | 2.29 (1.02 ‐5.15) | 3.93 (1.63 ‐9.46) | 3.71 (1.56 ‐8.81) |
| North America | Reference | Reference | Reference | Reference |
| Asia, Australia, New Zealand, Africa, Turkey | 0.99 (0.3‐3.23) | 0.95 (0.29‐3.04) | 0.83 (0.20‐3.42) | 0.88 (0.22‐3.62) |
| South America | 3.62 (1.43‐9.17) | 3.55 (1.42‐8.85) | 1.74 (0.61‐5.01) | 1.71 (0.61‐4.82) |
| Past DMARD and methotrexate use | 0.0194 | 0.0002 | 0.0690 | 0.0825 |
| Both yes | Reference | Reference | Reference | Reference |
| Both no | 2.59 (1.22‐5.53) | 3.56 (1.91‐6.65) | 1.38 (0.63‐3.02) | 1.26 (0.61‐2.60) |
| DMARD, yes and methotrexate, no | 1.19 (0.42‐3.32) | 1.62 (0.63‐4.16) | 0.32 (0.10‐1.00) | 0.32 (0.10‐0.99) |
| ESR | 0.1905 | … | 0.8256 | … |
| Quartile 1 (2‐28 mm/h) | Reference | … | Reference | … |
| Quartiles 2‐4 (29‐160 mm/h) | 1.6 (0.79‐3.21) | … | 1.10 (0.47 ‐2.55) | … |
| HAQ‐DI | 0.0647 | 0.0444 | 0.3217 | 0.3209 |
| Quartile 1 (0‐1) | 1.77 (0.76‐4.13) | 1.80 (0.79‐4.07) | 1.91 (0.64‐5.71) | 1.83 (0.63‐5.34) |
| Quartiles 2‐3 (1.125‐2) | 0.84 (0.40‐1.77) | 0.83 (0.40‐1.71) | 1.11 (0.42‐2.90) | 1.06 (0.41‐2.72) |
| Quartile 4 (2.125‐3) | Reference | Reference | Reference | Reference |
| Hematocrit | 0.3272 | … | 0.5292 | … |
| Quartile 1 (29%‐36%) | Reference | … | Reference | … |
| Quartiles 2‐4 (37%‐51%) | 1.40 (0.72‐2.72) | … | 0.79 (0.38 ‐1.65) | … |
| CVD | 0.4435 | … | 0.3742 | … |
| Yes | Reference | … | Reference | … |
| No | 1.57 (0.5‐4.96) | … | 2.09 (0.41‐10.67) | … |
| Diabetes | 0.4003 | … | 0.0333 | … |
| Yes | 1.50 (0.58‐3.89) | … | 3.52 (1.10‐11.23) | … |
| No | Reference | … | Reference | … |
Abbreviation: AIC, Akaike information criterion; AUROC, area under the receiver operating characteristic curve; BIC, Bayesian information criterion; CDAI, Clinical Disease Activity Index; CI, confidence interval; CVD, cardiovascular disease; DMARD, disease‐modifying antirheumatic drug; ESR, erythrocyte sedimentation rate; HAQ‐DI, Health Assessment Questionnaire Disability Index; OR, odds ratio.
a
Presented for predictors: P value and OR (95% CI).
b
AIC and BIC selection results in the same model.