Accuracy of clinician probability estimates using different double thresholds (including indeterminate values)
| Estimate cut-off | Prediction* | Outcome (within 72 hours) | Outcomes | Proportion of indeterminate cases | |||
| Died | Survived | Total | |||||
| N | PPV | NPV | |||||
| >50% | Die | 787 | 478 | 1265 | 62% | ||
| <50% | Survive | 163 | 456 | 619 | 74% | ||
| 50%–50% | Indeterminate | 40 | 56 | 96 | 5% | ||
| ≥60% | Die | 766 | 446 | 1212 | 63% | ||
| ≤40% | Survive | 144 | 422 | 566 | 75% | ||
| 41%–59% | Indeterminate | 80 | 122 | 202 | 10% | ||
| ≥70% | Die | 685 | 356 | 1041 | 66% | ||
| ≤30% | Survive | 87 | 338 | 425 | 80% | ||
| 31%–69% | Indeterminate | 218 | 296 | 514 | 26% | ||
| ≥80% | Die | 577 | 247 | 824 | 70% | ||
| ≤20% | Survive | 39 | 256 | 295 | 87% | ||
| 21%–79% | Indeterminate | 374 | 487 | 861 | 43% | ||
| ≥90% | Die | 440 | 149 | 589 | 75% | ||
| ≤10% | Survive | 19 | 141 | 160 | 88% | ||
| 11%–89% | Indeterminate | 531 | 700 | 1231 | 62% | ||
*Each estimate was categorised in to a group if the estimate was above or below the cut-off. Scores that were indeterminate were omitted from the analysis. PPV (positive predictive value; the proportion of patients who died when the clinician predicted dying, eg, 787/1265 for the 50% cut-off), NPV (negative predictive value; the proportion of patients who survived when the clinician predicted survival, eg, 456/619 for the 50% cut-off).