Table 3. Risk Analysisi Index (RAI) Model Performance*.
| Robust | Normal | Frail | Very Frail | ||
|---|---|---|---|---|---|
| RAI-A | 2010–2014 VASQIP sample, N = 480,731 | ||||
| Score Range | ≤ 20 | 21–29 | 30–39 | ≥ 40 | |
| Predicted 30-day Mortality, % | 0.1 | 0.8 | 3.8 | 69.9 | |
| Predicted 180-day Mortality, % | 0.3 | 3.1 | 13.9 | 91.5 | |
| Sensitivity, % | 99.7 | 76.9 | 43.1 | 0.6 | |
| Specificity, % | 7.6 | 76.5 | 95.9 | 100.0 | |
| PPV, % | 3.9 | 10.8 | 27.9 | 79.0 | |
| NPV, % | 99.8 | 98.9 | 97.8 | 96.4 | |
| F1 | 0.6826 | 0.7672 | 0.5850 | 0.0113 | |
| MCC | 0.0366 | 0.2667 | 0.1946 | 0.0028 | |
| RAI-C | July-December 2016 UPMC Sample, N = 8,172 | ||||
| Score Range | ≤ 29 | 30–36 | 37–44 | ≥ 45 | |
| Predicted 180-day Mortality, % | 0.6 | 3.6 | 7.7 | 43.8 | |
| Sensitivity, % | 98.6 | 68.1 | 32.9 | 0.0 | |
| Specificity, % | 22.9 | 77.0 | 94.0 | 99.9 | |
| PPV, % | 3.3 | 7.3 | 12.8 | 0.0 | |
| NPV, % | 99.8 | 98.9 | 98.1 | 97.4 | |
| F1 | 0.7153 | 0.7127 | 0.4737 | 0 | |
| MCC | 0.1075 | 0.2255 | 0.1345 | -0.0005 | |
| RAI-ICD | 2020 National Inpatient Sample, N = 1,771,081 | ||||
| Score Range | < 27 | 27–35 | 36–45 | > 45 | |
| Predicted Mortality, % | 0.9 | 3 | 7.2 | 30.2 | |
| Sensitivity, % | 95.3 | 59 | 32.2 | 0.8 | |
| Specificity, % | 35.5 | 82 | 92.7 | 99.9 | |
| PPV, % | 2.3 | 14 | 29.7 | 82.4 | |
| NPV, % | 99.8 | 98 | 93.5 | 73.2 | |
| F1 | 0.7336 | 0.663 | 0.4617 | 0.0155 | |
| MCC | 0.1539 | 0.2025 | 0.1247 | 0.0036 | |
*
Threshold values for calculating dichotomous statistics set at the middle of the range of RAI score (for example, robust, normal, frail, and very frail) correspond to threshold values of RAI-A = 11, 25, 35, 61; RAI-C = 15, 33, 41, 63; and RAI-ICD = 14, 31, 41, 63, respectively). VASQIP, US Department of Veterans Affairs Surgical Quality Improvement Program; PPV, positive predictive value; NPV, negative predictive value; MCC, Matthews correlation coefficient; A, administrative; C, clinical; ICD, International Classification of Diseases.