Theodoropoulos 2013.

Methods	Single‐centre double‐blind RCT
Participants	Participants underwent colectomy for cancer No mention of participants undergoing chemotherapy or radiotherapy
Interventions	Synbiotics (combination of prebiotics and probiotics) (n = 38) Placebo (n = 35) Administration at the day participants were able to tolerate PO liquid diet and for 15 days thereafter
Outcomes	Primary endpoints: gastrointestinal function‐related quality of life at 1, 3, and 6 months postoperatively (using validated questionnaire GIQLI (Gastrointestinal Quality of Life Index)) Secondary endpoints: assessment of functional bowel disorders (diarrhoea, constipation) based on respective domains of the validated instrument EORTC‐QLQ‐C30
Notes	Clintrial.Gov trial ID NCT01479907 No mention of participants undergoing chemotherapy or radiotherapy Trial may be excluded in a future update

EORTC‐QLQ‐C30: questionnaire developed to assess the quality of life of patients with cancer, version 3.

GIQLI: Gastrointestinal Quality of Life Index.

PO: by mouth.

RCT: randomised controlled trial.