Ng 1992.

Methods	RCT. Individual women. 3‐arm study.
Participants	Inclusion criteria Women undergoing emergency CS. N = 145 in the cephalosporin vs penicillin comparison (though 222 in the whole study which included 'No antibiotic' group). Exclusion criteria Known hypersensitivity to either antibiotic, the presence of infection or fever before the operation, women already on antibiotics for any reason and women with multiple pregnancies.
Interventions	Intervention 1: cephalosporin (B3). Cefoperazone. 3 doses of 1g at 12‐hourly intervals. First dose given at induction of anaesthesia and the total number of doses of antibiotics given was calculated to give coverage for the first 24 hours after surgery. N = 71, then 1 excluded. Intervention 2: penicillin (A4). Ampicillin. 4 doses of 500 mg at 6‐hourly intervals. First dose given at induction of anaesthesia and the total number of doses of antibiotics given was calculated to give coverage for the first 24 hours after surgery. N = 74. Comparison No antibiotics. No data included in this review. N = 77, then 1 excluded.
Outcomes	Febrile morbidity; wound infection.
Notes	Dates: March to August 1991. Setting: Ipoh General Hospital, Ipoh, Perak Darul Ridzuan. Subgroups Non‐elective CS. Before cord clamping. Systemic. Multiple doses. Comparison 1 (subgroup 1); 10. No information about funding source of study. Inconsistency in data. There was inconsistency in the number of women reported in each group between the table and the text. We took the data from the tables and will write to the authors to seek clarification.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	A randomised trial.
Allocation concealment (selection bias)	Unclear risk	No information provided.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	No information provided.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	No information provided.
Incomplete outcome data (attrition bias) All outcomes	Low risk	2 women excluded ‐ 1 from each group.
Selective reporting (reporting bias)	Unclear risk	We did not assess the trial protocol.
Other bias	Unclear risk	Baseline characteristics similar for: age; race; parity; gestation. Other possible biases were unclear. No information about funding source of study.