Levy 1977.

Methods	RCT
Participants	50 IBS patients Unclear setting Diagnostic criteria not defined Mean age 48 years 46% female
Interventions	Spasmolytic Pinaverium tds 50 mg 15 days
Outcomes	Global assessment, dichotomous
Notes	No run‐in
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not described
Allocation concealment (selection bias)	Unclear risk	Not described
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Double‐blind, methods not described
Incomplete outcome data (attrition bias) All outcomes	Low risk	No drop outs
Selective reporting (reporting bias)	Low risk	Expected outcomes reported
Other bias	Low risk	The study appears to be free of other sources of bias