Table 3.
Diagnostic Test Characteristics of the Newly Derived CART Model for Estimating the Risk of Severe Acute Kidney Injury on Day 3 of Septic Shock
| Variable | CART-derived Model |
Day 1 KDIGO Status Model |
||
|---|---|---|---|---|
| Value | 95% CI | Value | 95% CI | |
| AUC | 0.95* | 0.92–0.98 | 0.87 | 0.82–0.93 |
| True positive, n | 60 | — | 55 | — |
| True negative, n | 280 | — | 254 | — |
| False positive, n | 34 | — | 60 | — |
| False negative, n | 5 | — | 10 | — |
| Sensitivity, % | 92 | 82–97 | 85 | 73–92 |
| Specificity, % | 89 | 85–92 | 81 | 76–85 |
| Positive predictive value, % | 64 | 53–73 | 48 | 38–57 |
| Negative predictive value, % | 98 | 96–99 | 96 | 93–98 |
| Positive likelihood ratio | 8.5 | 6.2–11.8 | 4.4 | 3.4–5.7 |
| Negative likelihood ratio | 0.09 | 0.04–0.20 | 0.2 | 0.1–0.3 |
Definition of abbreviations: AUC = area under the curve; CART = classification and regression tree; CI = confidence interval; KDIGO = Kidney Disease Improving Global Outcomes.
*
Ten-fold cross-validation, AUC = 0.88.