Table 4 Case-level performance metrics of the metamodel with full post-processing. The performance metrics for scans with hemorrhage are also stratified according to delay from symptom onset to imaging. TP = true positive, tn = true negative, fp = false positive, fn = false negative, fpr = false positive rate, npv = negative predictive value, ppv = positive predictive value, n/a = not applicable, ci = confidence interval.
TP | TN | FP | FN | Sensitivity % [95% CI] | Specificity % [95% CI] | FPR % [95% CI] | NPV % [95% CI] | PPV % [95% CI] | Accuracy % [95% CI] | |
|---|---|---|---|---|---|---|---|---|---|---|
All Scans | 106 | 6873 | 806 | 12 | 89.8% [84.4–95.3%] | 89.5% [88.8–90.2%] | 10.5% [9.8–11.2%] | 99.8% [99.7–99.9%] | 11.6% [9.5–13.7%] | 89.5% [88.8–90.2%] |
Symptom onset time confirmed < 12 h | 59 | 0 | 100% [100–100%] | N/A | N/A | N/A | N/A | 100% [100–100%] | ||
Symptom onset time presumably < 12 h | 19 | 0 | 100% [100–100%] | N/A | N/A | N/A | N/A | 100% [100–100%] | ||
Symptom onset time presumably 12–24 h or Confirmed 12–24 h | 13 | 4 | 76.5% [56.3–96.6%] | N/A | N/A | N/A | N/A | 76.5% [56.3–96.6%] | ||
Symptom onset time 24 h − 7 days | 10 | 4 | 71.4% [47.8–95.1%] | N/A | N/A | N/A | N/A | 71.4% [47.8–95.1%] | ||
Symptom onset time > 7 days or unclear | 5 | 4 | 55.6% [23.1–88.0%] | N/A | N/A | N/A | N/A | 55.6% [23.1–88.0%] | ||
Negative scans | 6873 | 806 | N/A | 89.5% [88.8–90.2%] | 10.5% [9.8–11.2%] | N/A | N/A | 89.5% [88.8–90.2%] |
