Hager 1983.

Methods	Randomized, placebo‐controlled trial; 2 parallel groups. Unit of randomization: individual.
Participants	Dates of data collection: not reported. Setting: Central Baptist Hospital, Lexington, Kentucky, US. Inclusion criteria: women undergoing primary, non‐elective CS (while it appears most women were in labor and/or had ruptured membranes it is unclear whether all patients fulfilled our criteria for non‐elective). N = 90. Exclusion: antibiotic use within 7 days, penicillin or cephalosporin allergy.
Interventions	Intervention: cefamandole 500 mg IV immediately after the cord was clamped, again in the recovery room and 2 more doses 6 hrs apart; N = 43. Comparison: placebo: identical‐appearing placebo; N = 47.
Outcomes	Infectious morbidity (fever > 100.3oF twice 6 hrs apart after 1st 24 hrs); endomyometritis (fever, uterine tenderness, and positive culture from endometrium); wound infection, UTI; maternal duration of stay (treatment 5.1 days vs placebo 5.4; not significant, no variance given).
Notes	There was 1 episode of bacteremia in the control group. Class of antibiotic: 2nd generation cephalosporin. Subgroups: type CS unclear; after cord clamping. The 2 groups were comparable regarding age, race, parity, weight, type of anesthesia, operating time or pre‐operative hematocrit.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "Randomized". Comment: no description of sequence generation process.
Allocation concealment (selection bias)	Low risk	Quote: "according to pre‐numbered envelopes maintained in the central pharmacy".
Incomplete outcome data (attrition bias) All outcomes	Low risk	Comment: no loss to follow‐up; no participant excluded; ITT analysis.
Selective reporting (reporting bias)	Unclear risk	Comment: insufficient information to judge.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote: "double‐blind".... "identical appearing, equal volume solution".
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Comment: insufficient information to judge.
Other bias	Low risk	Comment: no other sources of bias identified.