Study characteristics of included prediction model studies
| Study | Type of study | Model(s) | Source of data | Study population | Age, mean (SD) | Outcome* | Total outcome events, n (%) | Method of validation |
| Bont et al30 | D+V | New | Primary care cohort, retrospective | Elderly (≥65) LRTI patients | 75.5 (no SD) | Hospitalisation or all-cause mortality within 30 days | D: 274 (8.7), V: 178 (7.2) | Internal (random split-sample) and external |
| Bont et al 31 | V | CRB-65 | Primary care cohort, prospective | Elderly (≥65) patients with CAP | 77.3 (no SD) | Mortality within 30 days | 11 (3.5) | External |
| Ochoa-Gondar et al 32 | V | PSI, CURB-65, CRB-65 | Population-based cohort, retrospective | Elderly (≥65) patients with radiographically confirmed CAP | 77.4 (7.6) | Mortality within 30 days | 80 (13.6) | External |
| Francis et al 33 | V | CRB-65 | Primary care cohort, prospective | Adults (≥18) presenting with acute cough or suspected LRTI | 49.3 (16.5) | Hospitalisation within 28 days | 10 (2.9) | External |
| Ochoa-Gondar et al 201334 | D+V | CORB-75 (new), CRB-65 | Population-based cohort, retrospective | Elderly (≥65) patients with radiographically confirmed CAP | 78.1 (7.7) | Mortality within 30 days | D: 46 (13.1), V: 34 (13.1) | Internal-external (temporal, CORB-75), external (CRB-65) |
| Bruyndonckx et al35 | D (RISSC85)+V (all models) | RISSC85 (new), PSI (stage I), CRB, CRB-65, CURB, CURB-65 | Primary care cohort, prospective | Adults (≥18) with symptoms suggestive of LRTI | 50 (17) | Reconsultation with new/worsened symptoms or hospitalisation within 28 days | 521 (20.0) | Internal (random split sample, RISSC85), external (other models) |
| Moore et al 36 | D+V | New | Primary care cohort, prospective | Patients ≥16 years with acute cough attributed to LRTI | NR | Hospitalisation, mortality, or clinical diagnosis of pneumonia within 2–30 days | 325 (1.1) | Internal (bootstrapping) |
*Time window of outcome is defined as days from first consultation.
CAP, community acquired pneumonia; CORB-75, confusion, oxygen saturation ≤90%, respiratory rate ≥30/minute, and systolic blood pressure ≤90mmHg or diastolic blood pressure ≤60mmHg, and age ≥75 years; CRB-65, Confusion, respiratory rate ≥30/minute, systiolic blood pressure ≤90mmHg or diastolic blood pressure ≤60mmHg, and age ≥65 years ; CRB, Confusion, respiratory rate ≥30/minute, and systiolic blood pressure ≤90mmHg or diastolic blood pressure ≤60mmHg ; CURB-65, Confusion, blood urea nitrogen >7 millimole/liter, respiratory rate ≥30/minute, systiolic blood pressure ≤90mmHg or diastolic blood pressure ≤60mmHg, and age ≥65 years ; CURB, Confusion, blood urea nitrogen >7 millimole/liter, respiratory rate ≥30/minute, and systiolic blood pressure ≤90mmHg or diastolic blood pressure ≤60mmHg; D, development; LRTI, lower respiratory tract infection; NR, not reported; PSI, Pneumonia Severity Index; RISCC85, a priori risk of poor outcome by country, inference in daily activities, number of years stopped smoking, severe sputum, presence of crackles, and diastolic blood pressure <85mmHg; V, validation.