Rasooli 2014.

Study characteristics
Methods	RCT
Participants	Inclusiom criteria: Women for elective CS under spinal anaesthesia ASA 1 or 2, 20–30 years N = 90 Exclusion criteria:
Interventions	Intervention 1: sedative (Comparison 6) Propofol 20 mg + 1 mg/kg/hr. bolus and infusion, after cord clamping N = 30. Intervention 2: sedative (Comparison 6) Midazolam 1 mg + 1.0 mg/kg/hour bolus infusion after cord clamping N = 30 Comparison: placebo Bolus + infusion of saline. N = 30.
Outcomes	nausea and vomiting and retching on 4‐point score
Notes	Setting: Al‐Zahra Obstetrics and Gynecology Educational Hospital, Tabriz, Iran. Dates: not reported. Funding source: not reported. Declaration of interest: not reported. Looks like N&V only examined intra‐op. Authors do not state if post‐op N&V specifically looked at. Drugs are in separate subgroups but then pooled in our analysis, so the placebo data are dealt with according to our methods (Unit of analysis issues)
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Unspecified: quote: "randomly allocated"
Allocation concealment (selection bias)	Unclear risk	Solutions were prepared by an assistant not involved in care
Blinding of participants and personnel (performance bias) All outcomes	High risk	Quote: "Double blind". However patients could see what infusion they were receiving (propofol)
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Assessments by blinded third party
Incomplete outcome data (attrition bias) All outcomes	Low risk	None
Selective reporting (reporting bias)	Unclear risk	Specified endpoints; possibly low risk?
Other bias	Unclear risk	VAS scores apparently taken but not reported