Sensitivity, specificity, positive and negative predictive values of 30 day mortality of the different predictive rules*
| Cut-off points | Sensitivity | Specificity | Positive predictive value | Negative predictive value |
|---|---|---|---|---|
| *All numbers are percentages | ||||
| †Cut-off points accepted as threshold to define low-risk group according to original study design.11,13 | ||||
| PSI risk class | ||||
| ⩾I | NA | NA | NA | NA |
| ⩾II | 100 | 0.0 | 8.6 | NA |
| ⩾III | 97.7 | 25.8 | 11.0 | 99.2 |
| ⩾IV† | 83.9 | 50.2 | 13.6 | 97.1 |
| V | 46.0 | 84.8 | 22.1 | 94.4 |
| CURB65 score | ||||
| ⩾0 | 100 | 0.0 | 8.6 | NA |
| ⩾1 | 98.9 | 11.4 | 9.5 | 99.1 |
| ⩾2† | 85.1 | 46.0 | 12.8 | 97.0 |
| ⩾3 | 58.6 | 77.4 | 19.5 | 95.2 |
| ⩾4 | 23.0 | 94.4 | 27.8 | 92.9 |
| 5 | 3.4 | 99.5 | 37.5 | 91.7 |
| CRB65 scores | ||||
| ⩾0 | 100 | 0.0 | 8.6 | NA |
| ⩾1† | 96.6 | 13.5 | 9.5 | 97.7 |
| ⩾2 | 67.8 | 63.4 | 14.8 | 95.5 |
| ⩾3 | 29.9 | 91.5 | 24.8 | 93.3 |
| 4 | 4.6 | 99.4 | 40.0 | 91.7 |