D'Angelo 1980.

Methods	RCT; 3 parallel groups. Unit of randomization: individual.
Participants	Dates of data collection: not stated. Setting: Cleveland, Ohio, USA. Inclusion criteria: women in labor with ruptured membranes requiring internal monitoring (non‐elective delivery). N = 80. Exclusion criteria: evidence of infection; penicillin or cephalosporin allergy.
Interventions	Intervention 1: cephalosporin: cefazolin, 1 g IV short course ‐ 6 hrly for 24 hrs; N = 24. Intervention 2: cephalosporin: cefazolin, 1 g IV long course ‐ for 8 or more doses and cephalexin 500 mg orally 6 hrly for 5 days; N = 25. Comparison: no treatment: no prophylactic antibiotics; N = 31. Short and long courses of cephalosporins combined for this review. Administered after umbilical cord clamping.
Outcomes	Endometritis and/or wound infection (antibiotic 12/49 vs control 20/31).
Notes	It was possible to deduce the rate of endometritis alone, but not wound infection, for this review. 1 late infectious complication (wound dehiscence) in control group. Drug class: 1st generation cephalosporin. Subgroups: non‐elective CS; after cord clamping. There were no statistical differences among the 3 groups for potential risk factors.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote:"Randomly assigned". Comment: no description of sequence generation process.
Allocation concealment (selection bias)	Unclear risk	Comment: no information provided.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Comment: no loss of participants to follow‐up; no participants excluded after analysis. ITT analysis.
Selective reporting (reporting bias)	Unclear risk	Comment: insufficient information to judge.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Comment: no blinding of participant or clinician; not placebo‐controlled.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Comment: probably outcome assessment was not blinded.
Other bias	Low risk	Comment: no other sources of bias identified.