Table 4.
Predictive performance of the disease risk score (DRS) models in the cyclooxygenase-2 inhibitor versus non-selective non-steroidal anti-inflammatory drugs in historical and concurrent cohorts
| Num. | Model data component and dimension reduction/shrinkage method | EPVc | Historical cohort | Concurrent cohort | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| nsNSAID initiators | nsNSAID initiators | coxib initiators | |||||||||
| c-stat | 95 % CI | x-valid. c-stat | c-stat | 95 % CI | HL (P value) | c-stat | 95 % CI | HL (P value) | |||
| 1 | Demo (age + sex + race) | 40.2 | 0.64 | 0.60, 0.67 | 0.63 | 0.64 | 0.59, 0.70 | 9.6 (0.30) | 0.59 | 0.55, 0.63 | 24.4 (<0.01) |
| 2 | Demo + scorea | 33.5 | 0.66 | 0.62, 0.69 | 0.65 | 0.67 | 0.61, 0.72 | 9.6 (0.30) | 0.65 | 0.62, 0.68 | 34.2 (<0.01) |
| 3 | Demo + score + predef. | 7.2 | 0.70 | 0.67, 0.74 | 0.66 | 0.66 | 0.59, 0.72 | 12.0 (0.15) | 0.62 | 0.58, 0.66 | 41.2 (<0.01) |
| 4 | Demo + cov500 | 0.4 | 0.96 | 0.95, 0.97 | 0.71 | 0.45 | 0.38, 0.51 | >999 (<0.01) | 0.48 | 0.43, 0.52 | >999 (<0.01) |
| 5 | Demo + PCA(10) | 13.4 | 0.72 | 0.68, 0.75 | 0.68 | 0.66 | 0.60, 0.72 | 10.4 (0.24) | 0.63 | 0.59, 0.67 | 32.1 (<0.01) |
| 6 | Demo + PCA(30) | 5.7 | 0.75 | 0.72, 0.79 | 0.69 | 0.66 | 0.61, 0.72 | 12.4 (0.13) | 0.65 | 0.62, 0.69 | 56.5 (<0.01) |
| 7 | Demo + score + PCA(10) | 12.6 | 0.72 | 0.68, 0.75 | 0.68 | 0.66 | 0.60, 0.72 | 12.1 (0.15) | 0.62 | 0.58, 0.66 | 34.8 (<0.01) |
| 8 | Demo + score + PCA(30) | 5.6 | 0.75 | 0.72, 0.79 | 0.69 | 0.66 | 0.60, 0.72 | 12.6 (0.12) | 0.65 | 0.61, 0.69 | 58.5 (<0.01) |
| 9 | Demo + predef. + score + PCA(10) | 5.3 | 0.74 | 0.70, 0.77 | 0.67 | 0.65 | 0.59, 0.72 | 21.7 (0.01) | 0.60 | 0.56, 0.64 | 74.3 (<0.01) |
| 10 | Demo + predef. + score + PCA(30) | 3.5 | 0.78 | 0.75, 0.81 | 0.70 | 0.66 | 0.60, 0.72 | 23.6 (< 0.01) | 0.63 | 0.58, 0.67 | 102.6 (<0.01) |
| 11 | Ridge (Demo + predef. + score + cov500) | 0.4 | 0.92 | 0.90, 0.93 | 0.77 | 0.55 | 0.48, 0.62 | 77.3 (<0.01) | 0.59 | 0.54, 0.63 | 172.9 (<0.01) |
| 12 | Ridge (Demo + predef. + score + PCA(30)) | 3.5 | 0.77 | 0.74, 0.80 | 0.71 | 0.67 | 0.61, 0.72 | 11.9 (0.16) | 0.64 | 0.60, 0.68 | 35.2 (<0.01) |
| 13 | Lasso (Demo + predef. + score + cov500) | 0.4 | 0.93 | 0.91, 0.94 | 0.72b | 0.53 | 0.46, 0.60 | 409 (<0.01) | 0.57 | 0.52, 0.61 | 578.8 (<0.01) |
| 14 | Lasso (Demo + predef. + score + PCA(30)) | 3.5 | 0.78 | 0.74, 0.81 | 0.72 | 0.67 | 0.61, 0.73 | 9.1 (0.33) | 0.65 | 0.61, 0.69 | 38.3 (<0.01) |
c-stat c-statistics, coxibs cyclooxygenase-2 inhibitors, Demo demographic variables, HL Hosmer–Lemeshow test statistics, nsNSAIDs non-selective nonsteroidal anti-inflammatory drug, Num. model number, PCA(10) top 10 components from principal component analysis, PCA(30) top 30 components from principal component analysis, predef. predefined variables, x-valid. 10-fold cross-validated
aScore = combined comorbidity score [24]
bAverage of 3 of 10 which reached convergence in the 10-fold cross-validation, the rest did not reach convergence
cEvent per variable: ratio between the number of outcome and number of variables included in the model