Moslemi 2015.

Study characteristics
Methods	RCT
Participants	90 recruited, 83 completed analysis Inclusion criteria: healthy pregnancy of gestational age 36 weeks or higher, non‐emergency CS Exclusion criteria: below 36 weeks' gestation, emergence CS, high‐risk pregnancies (multiple gestations, intrauterine growth retardation, pre‐eclampsia, maternal cardiovascular or respiratory diseases), any contraindication of spinal anaesthesia (patient refusal, coagulopathy, haemorrhage or hypovolaemic shock), unexpected events during surgery (haemorrhage, sensory block higher or lower than T4‐T5 after spinal anaesthesia) Setting: Iran
Interventions	Phenylephrine versus ephedrine versus crystalloid Group 1: 450 μg phenylephrine in 250 cc normal saline administered over 30 min after preload Group 2: 45 mg ephedrine in 250 cc normal saline administered over 30 min Group 3: 250 cc normal saline infused over 30 min All women received standardised monitoring, standardised crystalloid preload and standardised spinal anaesthetic technique and dose. Hypotension was treated with study vasopressor (clinician blinded to which vasopressor): Group 1 received 50‐100 μg phenylephrine Group 2 and 3 received 5‐10 mg ephedrine.
Outcomes	Maternal: incidence and degree of hypotension, heart rate and rhythm, nausea/vomiting, number of vasopressor therapy and total dose, "any other intra or post‐operative complication". Neonatal: arterial blood gas, Apgar at 1 min and 5 min
Notes	Hypotension defined as drop in BP > 20% baseline
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer‐generated randomisation list
Allocation concealment (selection bias)	Unclear risk	Not reported
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Study drugs labelled with numerical codes and investigators were blinded Double‐blinded
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Double‐blinded
Incomplete outcome data (attrition bias) All outcomes	Low risk	Group 1: 4 excluded due to very high or very low sensory block Group 2: 3 excluded due to very high or very low block
Selective reporting (reporting bias)	Low risk	Group 1: 4 excluded due to very high or very low sensory block Group 2: 3 excluded due to very high or very low block
Other bias	Low risk	None apparent Funded by: University of Medical Sciences and Women's Reproductive Health Research Centre