Uchino 2019.

Study characteristics
Methods	Study design: Parallel‐group randomised trials Duration of trial: March 2014 to February 2017 Duration of follow‐up: Quote: "The wounds were inspected daily by a nurse, once a week by the surveillance member, and an attending physician during the hospital stay, and at the 4‐week and 3‐month postoperative follow‐up visits." Country of origin: Japan
Participants	Baseline characteristics Number randomised: 325 participants Number analysed: 321 participants Number eligible and included in this review: 185 Only a subset of the study patients was included in the meta‐analysis. All patients who underwent colon or rectal surgery with intestinal anastomosis were eligible. Intervention: MBP+oAB Number of participants [n]: 91 Age: ‐ Gender [male/female; n]: 69/22 Control: nBP Number of participants [n]: 94 Age: ‐ Gender [male/female; n]: 77/17 Inclusion criteria  "Patients undergoing surgery for Crohn disease." Exclusion criteria Quote: "Patients with emergent surgery, allergy to antibiotics, and antibiotic use within the 2 weeks before surgery were excluded. Moreover, patients treated with a long‐tube insertion due to bowel obstruction or surgery for an anal lesion alone were also excluded." Baseline imbalances None
Interventions	Comparison Intervention: MBP+oAB Control: MBP MBP Agent(s): 0.75 % sodium picosulfate hydrate magnesium citrate solution Dose per administration: 20 mL Time(s) of intake at 11:00 AM on the day before surgery Route:oral Concomitant medications: ‐ oAB Agent(s): kanamycin and metronidazole Dose per administration: 500 mg each Time(s) of intake: at 2:00 PM, 3:00 PM, and 9:00 PM on the day before surgery Route:oral Concomitant medications: ‐ Perioperative intravenous antibiotic prophylaxis Agent(s): fomoxef sodium Dose per administration: ‐ Time(s) of intake: 30 minutes before the surgery and repeatedly for every 3 hours during the surgery Adherence to regimen Quote: "Protocol violations were detected in 2 patients in group A and 3 patients in group B, and the remaining 320 patients were included in the PP analysis."
Outcomes	Outcomes sought in review and reported in trial SSI (incisional and organ/speace) Outcomes sought but not reported in trial Anastomotic leakage Mortality Length of hospital stay Postoperative complications (mild D/C I + II or severe D/C III+IV) Incidence of postoperative ileus Side effects of Intervention(s) Outcomes reported in trial but not used in review ‐
Notes	Source of funding: ‐ Conflicts of interest: Quote: "The authors report no conflicts of interest." Ethics approval:  Quote:"All study protocols were approved by the Institutional Review Board of the Hyogo College of Medicine (No. 1679)." Informed consent: Quote: "Informed consent was required from all participants" Clinical trials registration:Quote:  "The study protocols were registered with the University Hospital Medical Information Network Clinical Trials Registry (UMIN‐CTR 000013369)." Sample size calculation: Quote: "It was previously reported that the incidence of SSI in CD surgery without oral antibiotic prophylaxis was approximately 25%. When the power was set to 80%, it was assumed that 149 patients would be required in each group to detect a difference between an SSI rate of 12.5% and 25% (favoring oral antibiotic prophylaxis) with a probability of a type 1 error <0.05. To allow for the potential loss of evaluable patients, a total sample size of 160 patients in each arm was chosen."