Parra‐Guiza 2018.

Study characteristics
Methods	RCT
Participants	Inclussion criteria: Pregnant women scheduled for an elective CS with spinal anaesthesia N = 300 women randomised Exclusion criteria:
Interventions	Intervention 1: 5HT3 antagonist (Comparison 1) Ondansetron ‐ 4 mg IV N = 100 Intervention 2: corticosteroid (Comparison 3) Dexamethazone ‐ 4 mg IV N = 100 Comparator: placebo Saline IV N = 100
Outcomes	Nausea and vomiting, etc.
Notes	Setting: Columbia, South America Dates: February 2014 to September 2016 Funding source: Industrial University of Santander (Universidad Industrial de Santander) (from trial reg) Declaration of interest: authors declared no conflicts of interest (reported in Spanish at end or publication) No data available in the Abstract. Publication in Portuguese/Spanish (?) with abstract in English. No translation as yet Trial registration form reported under Guiza 2016, but publication indicated the first author should be Parra‐Guiza We will try to get a translation or contact the authors for further information.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not reported in the abstract translation.
Allocation concealment (selection bias)	Unclear risk	Not reported in the abstract translation.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Not reported in the translated abstract
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not reported in the translated abstract
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	No apparent loss of data after randomisation
Selective reporting (reporting bias)	Unclear risk	They do not report on pruritus in the abstract, yet this is the secondary outcome in the trial registration form. However, we do not have a translation of the paper yet, nor have we seen the trial protocol.
Other bias	Unclear risk	We were only able to assess the English abstract and so were unable to assess the whole paper.