Table 3.
Observed vs Predicted Mortality in the SMR-30 Validation Cohort Using 10 Equally Size Bins Defined by Decile of Predicted Risk
| Risk decile | Predicted risk (lowest, highest) | Hospitalizations, N | Observed deaths, N (%) | Predicted deaths, N (%) | Difference*, N (%) |
|---|---|---|---|---|---|
| 1 | (0.000–0.002) | 37,379 | 62 (0.17) | 47 (0.13) | 15 (0.04) |
| 2 | (0.002–0.004) | 37,379 | 94 (0.25) | 118 (0.32) | −24 (−0.06) |
| 3 | (0.004–0.007) | 37,379 | 154 (0.41) | 211 (0.56) | −57 (−0.15) |
| 4 | (0.007–0.011) | 37,379 | 252 (0.67) | 332 (0.89) | −80 (−0.21) |
| 5 | (0.011–0.016) | 37,379 | 384 (1.03) | 495 (1.33) | −111 (−0.30) |
| 6 | (0.016–0.023) | 37,380 | 541 (1.45) | 725 (1.94) | −184 (−0.49) |
| 7 | (0.023–0.035) | 37,379 | 926 (2.48) | 1077 (2.88) | −151 (−0.40) |
| 8 | (0.035–0.057) | 37,379 | 1572 (4.21) | 1686 (4.51) | −114 (−0.30) |
| 9 | (0.057–0.114) | 37,379 | 2951 (7.89) | 2991 (8.00) | −40 (−0.11) |
| 10 | (0.114–0.987) | 37,379 | 9100 (24.35) | 9775 (26.15) | −675 (−1.81) |
| 1–10 | (0.000–0.987) | 373,791 | 16036 (4.29) | 17458 (4.67) | −1422 (−0.38) |
*Differences reflect the observed minus predicted mortality. Negative values indicate that the model over-predicted mortality, while positive value indicate that the model under-predicted mortality
The expected (mean) absolute calibration error14 across risk decile was 0.38%, while the maximum calibration error14 (observed in the highest risk decile) was 1.81%