Methods	Randomised.
Participants	2289 women referred for Dopplers studies and for antenatal fetal monitoring
Interventions	Continuous wave Doppler studies of umbilical artery.
Outcomes	“Fetal outcome: perinatal mortality, Apgar score and admission to the neonatal unit. Obstetric intervention: admission to hospital, induction of labour and caesarean section. Use of tests of fetal well being: cardiotocography, biophysical profile and ultrasound biometry.”
Notes
Risk of bias
Bias	Authors’ judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not described.
Allocation concealment (selection bias)	Unclear risk	Not described.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Not blinded.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Not blinded.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Data appears to have been analysed according to the intention-to-treat principle. It states that 24 women randomised to Doppler didn’t have it carried out and 3 randomised to no Doppler, actually had Dopoler. Data on outcomes in table 3 suggest analysis was based on randomised groups Loss to follow-up - one patient appears to be missing from non Doppler group - table 4 - so minimal loss
Selective reporting (reporting bias)	Low risk	All outcomes specified within the abstract are reported upon in the paper
Other bias	Low risk	Baseline characteristics similar. “The treatment and control groups were comparable in age, parity, gestation at point of entry and risk features.”