Table 2.
Sensitivity, specificity, PPV, NPV, and under- and over-triage for DC A and B before and after merging (A + B)
| DC A % (95% CI) | DC B % (95% CI) | A + B % (95% CI) | |
|---|---|---|---|
| Sensitivity | 86.0 (85.6–86.4) | 91.6 (91.0–92.2) | 86.8 (86.5–87.1) |
| Specificity | 48.0 (47.4–48.6) | 20.3 (19.4–21.2) | 67.4 (66.9–67.9) |
| PPV | 21.7 (21.2–22.2) | 16.1 (15.3–16.9) | 29.2 (28.7–29.7) |
| NPV | 95.4 (95.2–95.6) | 93.5 (93.0–94.0) | 97.0 (96.8–97.2) |
| Over-triage | 78.0 (77.5–78.5) | 83.9 (83.1–84.7) | 70.8 (70.3–71.3) |
| Under-triage | 4.6 (4.4–4.8) | 6.5 (6.0–7.0) | 3.0 (2.8–3.2) |
Over-triage = P1 dispatch with NACA <4 (false positives)/all P1 dispatch (false positives + true positives) Under-triage = P2 or 3 dispatch with NACA >3 (false negatives)/all P2 or P3 dispatch (false negatives + true negatives) Sensitivity was calculated as true positives/(true positives + false negatives); specificity as true negatives/(false positives + true negatives) Positive predictive value (PPV) was calculated as true positives/(true positives + false positives); negative predictive value (NPV) as true negatives/(true negatives + false negatives)