Proportion of patients with pneumonia | Radiograph within 1 week | Adjusted risk ratio# for pneumonia on radiograph in imputed dataset | ||||||
Risk ratio for pneumonia on radiograph | Adjusted risk ratio# for pneumonia on radiograph | |||||||
Characteristic present | Characteristic absent | Risk ratio (95% CI) | p-value | Risk ratio (95% CI) | p-value | Risk ratio (95% CI) | p-value | |
Symptoms | ||||||||
Shortness of breath | 90/525 (17.1%) | 22/189 (11.6%) | 1.47 (0.95–2.28) | 0.081 | ||||
Fever or chills | 73/352 (20.7%) | 40/366 (10.9%) | 1.90 (1.33–2.71) | <0.001 | 1.32 (0.92–1.91) | 0.134 | 1.31 (0.78–2.22) | 0.307 |
Chest pain | 57/317 (18.0%) | 55/398 (13.8%) | 1.30 (0.93–1.83) | 0.129 | ||||
Confusion | 13/49 (26.5%) | 102/671 (15.2%) | 1.75 (1.06–2.87) | 0.029 | 1.46 (0.63–3.39) | 0.378 | 1.84 (0.86–3.94) | 0.117 |
No coryza | 64/396 (16.2%) | 47/318 (14.8%) | 1.09 (0.77–1.55) | 0.613 | ||||
Headache | 56/293 (19.1%) | 56/422 (13.3%) | 1.44 (1.03–2.02) | 0.035 | 1.21 (0.84–1.73) | 0.320 | 1.39 (0.85–2.25) | 0.186 |
Muscle aches | 52/270 (19.3%) | 59/444 (13.3%) | 1.45 (1.03–2.04) | 0.030 | 0.93 (0.58–1.51) | 0.780 | 1.16 (0.70–1.94) | 0.559 |
Diarrhoea | 13/68 (19.1%) | 101/650 (15.5%) | 1.23 (0.73–2.07) | 0.435 | ||||
Sputum | ||||||||
Purulent | 71/408 (17.4%) | 44/312 (14.1%) | 1.23 (0.87–1.74) | 0.234 | ||||
Bloody/rusty | 18/100 (18.0%) | 97/620 (15.7%) | 1.07 (0.85–1.35) | 0.547 | ||||
Clinical examination | ||||||||
Severity assessment ≥5/10 | 78/430 (18.1%) | 37/290 (12.8%) | 1.42 (0.99–2.04) | 0.057 | ||||
Respiratory rate ≥24 min–1 | 26/117 (22.2%) | 89/601 (14.8%) | 1.50 (1.02–2.22) | 0.041 | 1.01 (0.51–1.98) | 0.980 | 0.81 (0.44–1.46) | 0.481 |
Temperature ≥37.8°C | 29/76 (38.2%) | 86/644 (13.4%) | 2.86 (2.02–4.04) | <0.001 | 2.37 (1.62–3.46) | <0.001 | 2.65 (1.46–4.81) | 0.001 |
Pulse ≥100 min–1 | 31/115 (27.0%) | 84/605 (13.9%) | 1.94 (1.35–2.78) | <0.001 | 1.45 (1.00–2.11) | 0.046 | 1.90 (1.12–3.24) | 0.018 |
Oxygen saturation <95% | 26/100 (26.0%) | 76/532 (14.3%) | 1.82 (1.23–2.69) | 0.003 | 1.42 (0.99–2.05) | 0.042 | 1.73 (0.98–3.06) | 0.050 |
SBP ≤90 mmHg or DBP ≤60 mmHg | 13/68 (19.1%) | 102/652 (15.2%) | 1.22 (0.73–2.06) | 0.450 | ||||
Crackles | 2.15 (1.47–3.16) | <0.001 | 1.69 (1.11–2.58) | 0.009 | 1.82 (1.12–2.97) | 0.015 | ||
Bronchial breathing | 1.33 (0.84–2.11) | 0.229 | ||||||
Wheeze | 1.02 (0.71–1.46) | 0.929 |
#: risk ratio adjusted for those variables that were significantly associated with the outcome in the univariate model. SBP: systolic blood pressure; DBP: diastolic blood pressure.