Lapas 1988.

Methods	Double blind, placebo‐controlled trial; 2 parallel groups. Unit of randomization: individual.
Participants	Dates of data collection: not reported. Setting: Athens, Greece. Inclusion criteria: women undergoing elective or non‐elective CS. Age range 17‐40 years. N = 100. Exclusion criteria: allergy to metronidazole, amnionitis, and pyrexia.
Interventions	Intervention: Nitroimidazole: metronidazole 500 mg IV 2 hrs or immediately pre‐operatively, 500 mg intraoperatively, 1000 mg 8 hrs post‐operatively; N = 50. Comparison: placebo: placebo; N = 50.
Outcomes	Wound infection; endometritis; inadequate wound healing (metronidazole 1/50 vs placebo 8/50); mean temperature (36.8oC SD 1.02 vs 37.6, 1.03); duration of hospital stay.
Notes	Although the authors are not identical and the presentation of the data makes direct comparisons difficult, the description of the 2 studies cited is so similar that it is presumed the 2 citations refer to the same patient population. Translated from Bulgarian. Class of antibiotic: nitroimidazole (metronidazole). Subgroups: both elective and non‐elective CS; before cord clamping. There was no significant difference in parity and age between the groups.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "Women were divided into 2 groups". Comment: insufficient information to judge.
Allocation concealment (selection bias)	Unclear risk	Comment: no information provided.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Comment: no information available.
Selective reporting (reporting bias)	Unclear risk	Comment: insufficient information to judge.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Comment: double‐blind; placebo‐controlled.
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.