Busowski 2000.

Methods	RCT. Individual women. 3‐arm study.
Participants	Inclusion criteria Women undergoing CS following labour for > 2 hours without evidence of infection. N = 114. Exclusion criteria Inability to understand or give consent; oral temperature > 1000F; antibiotic treatment within 72 hours prior to birth; allergies to study antibiotics; intention to breastfeed. Requirement of additional antibiotics during or after CS ‐ this may contribute to high risk of bias through exclusion after randomisation.
Interventions	Intervention: cephalosporin (B2). Cefotetan. 1 g, single dose, IV. N = 42. Comparison 1: penicillin (A4) combination Ampicillin +sulbactam. 1.5 g. N = 33. Comparison 2 Ciprofloxacin ‐ fluoroquinolone ‐ 2nd generation (C2). N = 39.
Outcomes	Endometritis; pneumonia; bacteraemia; UTI; would infection; postpartum stay > 6 days.
Notes	Setting: Tampa General Hospital, US. Subgroups Non‐elective CS. After cord clamping. IV administration. Single dose. Comparisons: 1(subgroup 2); 2; 3; 4; 11; 12. No information about funding source of study.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	“... prospectively randomised...”
Allocation concealment (selection bias)	Unclear risk	“... prospectively randomised...”
Blinding of participants and personnel (performance bias) All outcomes	Low risk	· “Investigators were blinded to treatment.”
Blinding of outcome assessment (detection bias) All outcomes	Low risk	· “Investigators were blinded to treatment.”
Incomplete outcome data (attrition bias) All outcomes	Low risk	No loss to follow‐up.
Selective reporting (reporting bias)	Unclear risk	We did not asses trial protocol.
Other bias	Unclear risk	Baseline characteristics similar for: primaparous; weight; gestation; race; repeat CS; Hb but there was a statistically significant difference in age considered not to be clinically important. Other aspects of bias were unclear. No information about funding source of study.