TABLE 4

Clinical symptoms and examination findings at presentation predicting radiographic pneumonia on chest radiography

Proportion of patients with pneumoniaRadiograph within 1 weekAdjusted risk ratio# for pneumonia on radiograph in imputed dataset
Risk ratio for pneumonia on radiographAdjusted risk ratio# for pneumonia on radiograph
Characteristic presentCharacteristic absentRisk ratio (95% CI)p-valueRisk ratio (95% CI)p-valueRisk ratio (95% CI)p-value
Symptoms
 Shortness of breath90/525 (17.1%)22/189 (11.6%)1.47 (0.95–2.28)0.081
 Fever or chills73/352 (20.7%)40/366 (10.9%)1.90 (1.33–2.71)<0.0011.32 (0.92–1.91)0.1341.31 (0.78–2.22)0.307
 Chest pain57/317 (18.0%)55/398 (13.8%)1.30 (0.93–1.83)0.129
 Confusion13/49 (26.5%)102/671 (15.2%)1.75 (1.06–2.87)0.0291.46 (0.63–3.39)0.3781.84 (0.86–3.94)0.117
 No coryza64/396 (16.2%)47/318 (14.8%)1.09 (0.77–1.55)0.613
 Headache56/293 (19.1%)56/422 (13.3%)1.44 (1.03–2.02)0.0351.21 (0.84–1.73)0.3201.39 (0.85–2.25)0.186
 Muscle aches52/270 (19.3%)59/444 (13.3%)1.45 (1.03–2.04)0.0300.93 (0.58–1.51)0.7801.16 (0.70–1.94)0.559
 Diarrhoea13/68 (19.1%)101/650 (15.5%)1.23 (0.73–2.07)0.435
 Sputum
  Purulent71/408 (17.4%)44/312 (14.1%)1.23 (0.87–1.74)0.234
  Bloody/rusty18/100 (18.0%)97/620 (15.7%)1.07 (0.85–1.35)0.547
Clinical examination
 Severity assessment ≥5/1078/430 (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)0.0411.01 (0.51–1.98)0.9800.81 (0.44–1.46)0.481
 Temperature
≥37.8°C
29/76 (38.2%)86/644 (13.4%)2.86 (2.02–4.04)<0.0012.37 (1.62–3.46)<0.0012.65 (1.46–4.81)0.001
 Pulse ≥100 min–131/115 (27.0%)84/605 (13.9%)1.94 (1.35–2.78)<0.0011.45 (1.00–2.11)0.0461.90 (1.12–3.24)0.018
 Oxygen saturation
<95%
26/100 (26.0%)76/532 (14.3%)1.82 (1.23–2.69)0.0031.42 (0.99–2.05)0.0421.73 (0.98–3.06)0.050
 SBP ≤90 mmHg or DBP ≤60 mmHg13/68 (19.1%)102/652 (15.2%)1.22 (0.73–2.06)0.450
 Crackles2.15 (1.47–3.16)<0.0011.69 (1.11–2.58)0.0091.82 (1.12–2.97)0.015
 Bronchial breathing1.33 (0.84–2.11)0.229
 Wheeze1.02 (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.