Table 2 Risk stratification capacity of the original model: observed vs. predicted risk
Predicted risk (%) | No. of births per stratum (% of sample) | Observed risk (%) | Likelihood ratio (95 % CI) |
|---|---|---|---|
<3.0 | 5,788 (7.7) | 134 (2.3) | 0.3 (0.2–0.3) |
3.0–5.5 | 21,654 (28.8) | 876 (4.0) | 0.4 (0.4–0.4) |
5.5–12.0 a | 33,178 (44.11) | 2,846 (8.6) | 1.0 (1.0–1.1) |
12.0–15.0 | 5,960 (7.9) | 800 (13.4) | 1.7 (1.6–1.8) |
>15.0 | 8,645 (11.5) | 1,660 (19.2) | 2.7 (2.6–2.9) |
Total | 75,225 (100.0 %) | 6,313 (8.4) | - |