Shah 1998.

Methods	RCT; 4 parallel groups. Unit of randomization: individual.
Participants	Dates of data collection: not reported. Setting: United Arab Emirates. Inclusion criteria: women undergoing elective CS (definition not provided). N = 198. Exclusion: hypersensitivity to penicillin or cephalosporin; prior antibiotic therapy within 3 days; hepatorenal insufficiency; positive cultures or definite evidence of infection.
Interventions	Intervention: penicillin (A3): pipericillin 4 g IV after the cord was clamped; N = 48. Intervention: penicillin (A3): piperacillin 2 g IV after clamping of the cord and 2 g every 8 hrs x 2; N = 52. Intervention: drug combination [cephalosporin (B1) plus nitroimidazole (I)]: cephradine 500 mg plus metronidazole 500 mg both IV after the cord was clamped and every 8 hrs x 2; N = 47. Comparison: no treatment: no treatment; N = 51. Results of the 2 penicillin treatment groups were combined for this review. Placebo data were divided: 2/3 for comparison with penicillin (A) and 1/3 for comparisons with the cephalosporin.
Outcomes	Febrile morbidity (fever > 38oC twice 4 hrs apart after 1st day); endometritis (uterine and parametrial tenderness, foul smelling vaginal discharge); wound infection (local induration and tenderness with wound exudate).
Notes	3 women who developed drug reactions were excluded from study (1 from each of the treatment groups). Late morbidity evaluated at 4‐6 weeks. Class of antibiotic: extended spectrum penicillin (ureidopenicillin (pipericillin)) vs other combination (1st generation cephalosporin plus nitroimidazole (metronidazole). Subgroups: elective CS; after cord clamping.
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: "...consecutively numbered sealed envelopes..".
Incomplete outcome data (attrition bias) All outcomes	High risk	Comment: 14 women were excluded (8/147 from treatment groups, 6/51 from control group). As‐treated analysis with available outcome data.
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, 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.