30-day mortality by different severity classes of CURB-65 and pneumonia severity index (PSI) in three age groups of patients
| PSI classification | Class I/II | Class III | Class IV/V |
| Whole cohort | 0.4% (1/266) | 0.5% (1/194) | 12.5% (66/527) |
| Age 18–64 | 0.4% (1/223) | 2.2% (1/45) | 20.0% (16/80) |
| Age 65–84 | 0% (0/43) | 0% (0/113) | 11.0% (31/282) |
| Age ≥85 | – | 0% (0/36) | 11.5% (19/165) |
| CURB-65 category | 0–1 | 2 | 3–5 |
| Whole cohort | 2.4% (12/493) | 7.8% (23/295) | 16.6% (33/199) |
| Age 18–64 | 2.5% (8/324) | 31.6% (6/19) | 80.0% (4/5) |
| Age 65–84 | 1.6% (2/127) | 4.8% (9/188) | 16.3% (20/123) |
| Age ≥85 | 4.8% (2/42) | 9.6% (8/88) | 23.1% (9/71) |