Zheng 2002.

Methods	Location: China Participants were assigned to treatments. The information about randomisation sequence generation, allocation concealment and blinding is not clear
Participants	80 hospitalised participants with acute purulent exacerbation of chronic bronchitis and aged more than 30 years. Participants having antibiotics within 48 hours and with known allergy to beta‐lactam antibiotics, beta‐lactamase inhibitors, serum creatinine > 200 mg/L and immunosuppressant users were excluded Participants: azithromycin group N = 38, amoxycillin/clavulanic group N = 42
Interventions	1. Azithromycin iv administration for 5 days, day 1 500 mg and days 2 to 5 250 mg 4 times a day 2. Amoxicillin/clavulanic acid iv administration for 7 days with 1.2 bid
Outcomes	Cure Improved Failure Adverse effect
Notes	—
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Participants were assigned to treatments. The method of randomisation was not clear
Allocation concealment (selection bias)	Unclear risk	No description of allocation method
Blinding (performance bias and detection bias) All outcomes	Unclear risk	Not described
Incomplete outcome data (attrition bias) All outcomes	Low risk	All randomised participants were evaluated
Selective reporting (reporting bias)	Unclear risk	The study protocol is not available
Other bias	Unclear risk	Baseline characteristics of the 2 treatment groups were not addressed

iv: intravenously
 N: number
 bid: two times a day
 tds: three times a day