Selzer 2020.

Study characteristics
Methods	RCT
Participants	Women undergoing elective CS under spinal anaesthesia (IT morphine) N = 122 women randomised
Interventions	Intervention: corticosteroid (Comparison 3) Dexamethasone 8 mg prior to CS IV N = 61 women were randomised and 55 analysed Group 2: placebo. Saline IV N = 61 women were randomised and 53 analysed
Outcomes	Nausea and vomiting (intra‐ and post‐op), pain, satisfaction.
Notes	Setting: New York‐Presbyterian Hospital/Weill Cornell Medicine in New York, NY, USA Dates: November 2012 to September 2014 Funding source: this study was funded by departmental support from the Department of Anesthesiology of Weill Cornell Medicine. There are no additional commercial or non‐commercial affiliations, associations, or sources of funding to disclose. Declaration of interest: authors declared none.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: “…a computer‐generated simple (non‐blocked) random number sequence…”
Allocation concealment (selection bias)	Unclear risk	No information on whether allocation was concealed it just reports: quote: “After randomization, the study drug…or placebo … was prepared by an unblinded investigator who had no further involvement in the study.”
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote: “All subjects, care providers, and data collectors were blinded to allocation
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: “All subjects, care providers, and data collectors were blinded to allocation
Incomplete outcome data (attrition bias) All outcomes	Low risk	122 women were randomised and data from 108 analysed (11% loss of data)
Selective reporting (reporting bias)	High risk	The method section said data would be collected at 0, 1, 3, 6, 24 and 48 hours, but the results section only reports one overall incidence throughout the 48 hours. It is unclear how this overall data were calculated.
Other bias	Unclear risk	They excluded women after randomisation if they did not receive the intervention of had a PPH, these women should have still been included, but only amount to 11% loss. It is unclear if there might be other biases.