Table 5.
Discrimination and calibration of APACHE III before and after customization for various subgroups of the validation sample
| Subgroup | Prediction | n | ROC area | H | C | SMR (95% CI) |
| Medical | Original | 590 | 0.861 | 22.01† | 24.90† | 1.15 (1.01-1.29) |
| Customized | 0.861 | 15.83* | 18.27* | 0.93 (0.81-1.06) | ||
| Surgical | Original | 299 | 0.842 | 8.51 | 13.18 | 1.28 (0.96-1.60) |
| Customized | 0.842 | 4.75 | 7.62 | 0.98 (0.71-1.25) | ||
| < 65 years | Original | 464 | 0.894 | 16.62* | 15.59* | 1.19 (0.95-1.42) |
| Customized | 0.894 | 21.24† | 10.19 | 0.94 (0.74-1.14) | ||
| ≥ 65 years | Original | 425 | 0.812 | 13.63 | 15.74* | 1.17 (1.02-1.33) |
| Customized | 0.812 | 12.93 | 9.42 | 0.95 (0.81-1.08) | ||
| Direct admission | Original | 614 | 0.874 | 19.41* | 23.46† | 1.29 (1.10-1.48) |
| Customized | 0.874 | 9.07 | 11.67 | 1.02 (0.86-1.18) | ||
| Transferral | Original | 275 | 0.817 | 9.54 | 12.18 | 1.05 (0.87-1.23) |
| Customized | 0.817 | 15.80* | 15.18* | 0.86 (0.70-1.01) | ||
| Cardiovascular | Original | 317 | 0.890 | 16.72* | 19.21* | 1.11 (0.92-1.35) |
| Customized | 0.890 | 18.47* | 15.61* | 0.90 (0.74-1.07) | ||
| Gastrointestinal | Original | 296 | 0.887 | 8.17 | 5.56 | 1.08 (0.81-1.34) |
| Customized | 0.887 | 7.80 | 5.26 | 0.85 (0.62-1.08) |
Direct admission is defined as admission from emergency room, operating theatre, or recovery room; and transferral is defined as admission from other hospital, other ICU, or floor. C, Hosmer-Lemeshow goodness-of-fit C test; H, Hosmer-Lemeshow goodness-of-fit H test; CI, confidence interval. *P < 0.05, †P = 0.01.