Khan 2013.

Study characteristics
Methods	RCT
Participants	100 women Inclusion criteria: ASA I‐II, age 20‐35, single pregnancy, elective caesarean under spinal anaesthesia Exclusion criteria: hypertension, congestive cardiac failure, cardiovascular disease, fetal distress, any contraindication to spinal anaesthesia, > 800 mL blood loss in theatre Setting: India
Interventions	Crystalloid preload versus crystalloid coload Group 1: preload of 20 mL/kg of Ringer's lactate over 20 min Group 2: coload of 20 mL/kg of Ringer's lactate at the maximal possible rate by pressurise giving set All women received no premedication, standardised cannulation, no further IV fluid except to keep IV line patent, standardised spinal anaesthetic technique and dose and standardised oxytocin postdelivery. Hypotension was treated with boluses of ephedrine 5 mg
Outcomes	Maternal: incidence of hypotension, height of sensory block, systolic/diastolic/mean BP, ephedrine requirement Neonatal: Apgar sores at 1 min and 5 min
Notes	Hypotension was defined as decrease in SBP > 20% from baseline or decrease of systolic pressure to < 90‐100 mmHg
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not reported
Allocation concealment (selection bias)	Unclear risk	Not reported
Blinding of participants and personnel (performance bias) All outcomes	Low risk	No blinding, but protocol well defined and seems unlikely to have affected results
Blinding of outcome assessment (detection bias) All outcomes	Low risk	No blinding, but protocol well defined and seems unlikely to have affected results
Incomplete outcome data (attrition bias) All outcomes	Low risk	Not reported
Selective reporting (reporting bias)	Low risk	Not apparent
Other bias	Low risk	Not apparent