Inclusion and Exclusion Criteria
| Inclusion criteriaa |
| Aged 5 years or older with clinically suspected CAP and either of the following features: |
| Feverb characterized by 1 of following: |
| >72 hours of fever and cough without any improvement |
| Fever >72 hours with purulent sputum |
| Fever with ≥1 of following: pleuritic pain; focal or asymmetric auscultation of crackles or hypoventilation; dyspnea (subjective); signs of breathing distress such as tachypnea, retractions, or nasal flaring (objective); SpO2 <95%; hemoptysis |
| Isolated fever without focus lasting >4 days |
| Reappearance or worsening of fever after clinical improvement of a respiratory condition |
| No fever, but presence of 1 of following: |
| Cough and purulent sputum lasting >4 days |
| Cough with ≥1 of following: pleuritic pain; focal or asymmetric auscultation of crackles or hypoventilation; dyspnea (subjective); signs of breathing distress such tachypnea, retractions, or nasal flaring (objective); SpO2 <95% |
| Cough lasting >4 weeks, even as an isolated symptom |
| Dyspnea in patients aged >75 years |
| Exclusion criteriac |
| Hospital admission within past 30 days (ie, possible nosocomial pneumonia instead of CAP) |
| Pneumonia already diagnosed during current illness by an imaging test |
| Receipt of antibiotics for current illness |
| Previous diagnosis of chronic obstructive pulmonary disease |
| Previous diagnosis of asthma, or suspicion of asthma attack or bronchial spasm in current illness |
| Children with previous diagnosis of recurrent wheezing related to viral infections in whom current illness suggests same diagnosis |
| Lung or pleural cancer |
| Previous pleurodesis |
| Previous thoracic surgery |
| Other chronic lung diseases (eg, pulmonary fibrosis) |
| Terminal disease (life expectancy <6 months) |
| Hemodynamic instability |
| Declined lung ultrasound and/or chest radiograph |
| Inability to go to the hospital for chest radiograph the same day |
| Declined to sign informed consent |
CAP = community-acquired pneumonia; SpO2 = peripheral oxygen saturation.
↵a Inclusion criteria were selected to avoid inclusion solely for clinical suspicion of pneumonia, a term that has greater potential subjectivity in its interpretation.
↵b Temperature ≥38°C not explained by extrathoracic symptoms.
↵c Exclusion criteria were primarily selected to avoid clinical conditions that might confound lung ultrasound findings.