| Methods |
Double‐blinded RCT |
| Participants |
164 people with a productive cough in conjunction with a cold or influenza‐like illness that had not resolved after 2 days |
| Interventions |
Self treatment with demethyl chlortetracycline (300 mg) or placebo twice daily for 5 days. Participants kept daily symptom logs. No initial or follow‐up visits |
| Outcomes |
Duration of and presence on day 5 of cough, productive cough, and purulent sputum; and duration of time off work |
| Notes |
These were unpublished data about a subgroup of patients with a cold or influenza‐like illness; total number of people who treated themselves for a single episode of illness and returned symptom cards = 301. |
| 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 |
Low risk |
|
| Selective reporting (reporting bias) |
Unclear risk |
Not reported |
| Other bias |
Low risk |
|
