Shah 1998.

Methods	RCT. Individual women. 4‐arm study.
Participants	Inclusion criteria Women undergoing elective CS. N = 147 in the cephalosporin comparisons (198 in total). Exclusion criteria Women who gave history of hypersensitivity to penicillin or cephalosporin and those having received antibiotic therapy within the last 3 days prior to surgery; women with severe hepato‐renal insufficiency (total bilirubin > 3 mg/100 ml and/or serum creatinine > 2.5 mg/100 ml); women with positive cultures prior to operation; definite clinical or laboratory evidence of infection where sampling for culture was not possible.
Interventions	Intervention: cephalosporin (B1) combination. Cephradine + metronidazole. 3 doses of 500 mg cephradine + 500 mg metronidazole; IV. N = 47. Comparison 1: penicillin (A3). Piperacillin ‐ single dose. 4 g; IV. N = 48. Comparison 2: penicillin (A3). Piperacillin ‐ multiple doses. 3 doses of 2 g each; IV. N = 52. Comparison 3: Data not included in this review. No antibiotics. Did not receive any prophylactic antibiotic and served as the control group. No other antibiotic was administered to any of these women during the study period. N = 51.
Outcomes	Post‐operative febrile morbidity; metritis with pelvic cellulitis; wound infection.
Notes	Dates: January 1995 to mid‐1996. Setting: Abu‐Dhabi, United Arab Emirates. Subgroups Elective CS. After cord clamping. IV administration. Single and multiple doses. Comparisons: 1 (subgroup 3); 2; 3; 4; 5. Single and multiple doses were pooled for the comparison between B1 and A3 (Comparison 5). No information about funding source of study.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Reports women were randomised and no further details.
Allocation concealment (selection bias)	Low risk	‘...consecutively numbered sealed envelopes...'.
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	11 out of 198 women (5.6%) were excluded during the course of the study.
Selective reporting (reporting bias)	Unclear risk	The study protocol was unavailable.
Other bias	Unclear risk	No information on the baseline characteristics of women in each group. Also other aspects of possible bias were unclear. No information about funding source of study.