| Methods |
RCT |
| Participants |
120 children, aged between 1 and 22 years, with cough due to upper respiratory tract infection, mean age 5 years, 25% male |
| Interventions |
3 arms: dextromethorphan 5 mg 6‐ to 8‐hourly; promethazine 0.5 mg/kg 8‐hourly; placebo for 3 days |
| Outcomes |
Cough frequency score; child's sleep score; parental sleep score; post‐tussive vomiting score; composite score of the above and adverse effects |
| Notes |
Adverse events were reported in 34% of participants taking dextromethorphan, 32% taking promethazine and 5% taking placebo. These included drowsiness, irritability, abdominal pain and nausea |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Low risk |
Computer‐generated |
| Allocation concealment (selection bias) |
Low risk |
Opaque envelopes |
| Blinding (performance bias and detection bias)
All outcomes |
Low risk |
Participants, treatment providers and outcomes assessors all blinded |
| Incomplete outcome data (attrition bias)
All outcomes |
Unclear risk |
100% adherence and follow‐up |
| Selective reporting (reporting bias) |
Unclear risk |
Not reported |
| Other bias |
Unclear risk |
Not reported |
