Soltoft 1976.

Methods	RCT
Participants	59 patients Setting unclear Mean age 40 years 64% female
Interventions	Bulking agent 6 weeks wheat bran 30 g/day
Outcomes	Global assessment, dichotomous
Notes	Unclear setting >1 week run‐in
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not described
Allocation concealment (selection bias)	Low risk	Adequate
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Double‐blind, placebo of similar appearance
Incomplete outcome data (attrition bias) All outcomes	Low risk	Missing outcome data balanced in numbers across intervention groups with similar reasons for missing data across groups
Selective reporting (reporting bias)	Low risk	All expected outcomes were reported
Other bias	Low risk	The study appears to be free of other sources of bias