Luo 2010.

Methods	RCT, single hospital, China.
Participants	300 women, all primiparas without previous abdominal surgeries, undergoing CS under epidural anaesthesia. No information on type of CS (elective or non‐elective).
Interventions	Intervention group (N = 150): chewing gum 4 times/d (2‐4 pieces each time) for 10‐15 minutes per session, (time chewing = 40‐60 min/d) from 2 h‐3 d after CS. Control group (N = 150): early feeding protocol (semi‐solid food after 6 h, normal diet after passage of flatus).
Outcomes	Time to first flatus and passage of faeces and also bowel sound (although this last was not prespecified as an outcome in Methods). Additional outcomes: incidence of abdominal distension, dry mouth, bad breath, incision pain.
Notes	No study protocol available.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No information available.
Allocation concealment (selection bias)	Unclear risk	No information available.
Blinding of participants and personnel (performance bias) All outcomes	High risk	The nature of the study did not allow blinding after assignment of the intervention postoperatively.
Blinding of outcome assessment (detection bias) Subjective outcomes	High risk	Participants were unable to be adequately blinded in relation to passage of flatus or stools.
Blinding of outcome assessment (detection bias) Objective outcomes	Unclear risk	No information about blinding of outcome assessors for time to first bowel sounds.
Incomplete outcome data (attrition bias) All outcomes	Low risk	No losses, all randomised participants included in results.
Selective reporting (reporting bias)	Low risk	All prespecified outcomes were reported. Bowel sound was reported in Results but was not a pre‐specified outcome.
Other bias	Unclear risk	No information available.