Davies 2006.

Study characteristics
Methods	RCT
Participants	70 women Inclusion criteria: ASA physical status I or II, women scheduled for elective CS under spinal anaesthesia, > 37 weeks' gestation Exclusion criteria: pregnancy‐induced hypertension, multiple pregnancy, fetal compromise, diabetes mellitus, polyhydramnios, weight > 100 kg, renal or hepatic disease, anaemia (haemoglobin < 10 g/dL), clotting Setting: UK
Interventions	Colloid: 5 mL/kg versus 10 mL/kg preload Group 1: 5 mL/kg pentastarch, volume preload before spinal anaesthesia (infused over 10 min) Group 2: 10 mL/kg pentastarch, volume preload before spinal anaesthesia (infused over 10 min) All women received standardised aspiration prophylaxis, a standardised spinal anaesthetic technique and dose, and standardised positioning. Hypotension requiring intervention was treated with 6 mg increments of ephedrine until resolution; smaller decreases in BP were similarly treated if accompanied by nausea, vomiting or dizziness.
Outcomes	Maternal: hypotension; ephedrine use Neonatal: Apgar score at 1 min
Notes	Hypotension was defined as a decrease in SBP to < 70% baseline or < 90 mmHg
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"Randomisation according to sealed envelopes"; no further details
Allocation concealment (selection bias)	Unclear risk	As above
Blinding of participants and personnel (performance bias) All outcomes	Low risk	"A technician prepared the calculated volume of pentastarch and covered it with a black bag to blind the anaesthetist to the volume administered."
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Not reported but probably done
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	No losses reported
Selective reporting (reporting bias)	Unclear risk	Not all expected outcomes were reported
Other bias	Low risk	Similar baseline characteristics