| Methods |
Double‐blinded RCT |
| Participants |
39 people (older than 12 years) with chief complaint of cough with purulent sputum and without the following: other known bacterial infection, flu‐like syndrome, chief complaint of coryza or sore throat with minimal sputum, or chest radiograph consistent with pneumonia (not all had radiographs). Dropouts = 8/31 |
| Interventions |
Doxycycline (100 mg twice daily on day 1 and 100 mg 4 times a day on days 2 to 7) versus placebo. Kept daily symptom log and had follow‐up visit at day 14 |
| Outcomes |
Cough, sputum, feverishness, days missed from work or normal activity, chest pain, dyspnoea, side effects |
| Notes |
No mention of eligible patients who refused to volunteer |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Unclear risk |
Not reported |
| Allocation concealment (selection bias) |
Low risk |
|
| Blinding (performance bias and detection bias)
All outcomes |
Low risk |
|
| Blinding (performance bias and detection bias) |
Low risk |
|
| Incomplete outcome data (attrition bias)
All outcomes |
Unclear risk |
Not reported |
| Selective reporting (reporting bias) |
Unclear risk |
Not reported |
| Other bias |
Low risk |
|
