Lemus 2005.

Methods	RCT; 2 parallel groups. Unit of randomization: individual.
Participants	Date of data collection: not reported. Setting: Hospital de Ginecologia y Obstetrcia num. 3 del Centro Medico La Raza, Mexico City, Mexico Inclusion criteria: women who had undergone CS with: no risk factors for wound infection at the time of the operation; no UTI or cervicovaginitis; intact membranes; less than 6 vaginal examination before the operation; no allergy to beta‐lactam antibiotics; clean surgical procedure without prolonged stage of labor (less than 33 minutes); primary closure of the incision; no use of drains. Exclusion criteria: women with medical factors that would lead to inadequate wound healing (diabetes, obesity, malnutrition); post‐surgical factors (asthma, pulmonary complications, coughing and vomiting after surgery); ascites; anemia; history of radiotherapy; anesthetic complications requiring intensive care admission; corticosteroid use; incomplete follow‐up.
Interventions	Intervention 1: cefotaxime 1 g every 8 hrs x 24 hrs; N = 500. Intervention 2: no treatment; N = 500.
Outcomes	Wound infection (follow‐up until day 30); definition of wound infection unclear.
Notes	Translated from Spanish Class of antibiotic: 3rd generation cephalosporin. Subgroups: elective CS (based on inclusion criteria stating labor of less than 33 minutes); after cord clamping (women had undergone CS).
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Quote: Women were allocated "at random and sequentially, but non‐random" as it depended on the obstetrician to start the prophylaxis perioperatively.
Allocation concealment (selection bias)	High risk	Comment: no information provided.
Incomplete outcome data (attrition bias) All outcomes	High risk	Comment: women with incomplete follow‐up were excluded.
Selective reporting (reporting bias)	Unclear risk	Comment: no information provided.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Comment: no blinding; not placebo‐controlled; obstetrician started prophylaxis.
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.