Lewis 2002.

Study characteristics
Methods	Study design: Parallel‐group randomised trials Duration of trial: 1992 ‐ 1995 Duration of follow‐up: Quote: "The patients were followed up by the infection control nurse on postoperative days 3, 5 to 7, 10 to 14, and at 1 month for diagnosis of surgical site infection, using the modified CDC criteria." Country of origin: Canada
Participants	Baseline characteristics Number randomised: 215 participants Number analysed: 213 participants Intervention: MBP+oAB Number of participants [n]: 108 Age [years; mean (SD)]: 68.8 (13.5) Gender [male/female; n]: 53/56 Control: MBP Number of participants [n]: 105 Age [years, mean (SD)]: 71.4 (12.9) Gender [male/female; n]: 43/63 Inclusion criteria  Quote: "All patients who underwent elective surgery of the colon at the Queen Elizabeth Hospital in Montreal were eligible to enter the study" Exclusion criteria Quote: "Patients who were allergic to the study antibiotics or who had received antibiotics within the 2 weeks before operation, pregnant patients and those who refused informed consent were excluded." Baseline imbalances Quote: "The treatment groups were evenly matched with respect to age, gender, body mass index and preoperative serum albumin level and blood lymphocyte count. There were no significant differences between the groups with respect to the preoperative final diagnoses and operations performed."
Interventions	Comparison Intervention: MBP+oAB Control: MBP MBP Agent(s): sodium phosphate (and saline enemas) Dose per administration: ‐ Time(s) of intake: Quote: "on the day before surgery until the rectal effluent was clear. If not, saline enemas were given at 1800 on the day before operation until they were clear" Route: oral/rectal Concomitant medications: ‐ oAB Agent(s): neomycin and metronidazole Dose per administration: 2 g each Time(s) of intake: at 19.00, and 23.00 hours on the day before surgery Route: oral Concomitant medications: ‐ Perioperative intravenous antibiotic prophylaxis Agent(s): amikacin and metronidazole Dose per administration: 1 g each Time(s) of intake: Quote: "On the way to the operating room" Adherence to regimen: ‐
Outcomes	Outcomes sought in review and reported in trial SSI Anastomotic leakage Outcomes sought but not reported in trial Mortality Incidence of postoperative ileus Postoperative complications (mild D/C I + II or severe D/C III+IV) Length of hospital stay Side effects of Intervention(s) Outcomes reported in trial but not used in review Organisms found in wound
Notes	Source of funding: ‐ Conflicts of interest: ‐ Ethics approval: ‐ Informed consent: Quote: "All patients gave informed consent to participate in the study" Clinical trials registration: ‐ Sample size calculation:Quote:  "The sample size was calculated assuming an infection rate at the surgical site of 10% to 15%, and a treatment difference of 10% (α risk 0.05, β risk 0.20)"