Methods	Randomised.
Participants	172 pregnant women with at least 34 weeks’ gestation and with no contraindications to contraction stress test
Interventions	Non-stress test versus fetal acoustic stimulation.
Outcomes	Mode of delivery, Apgar scores, perinatal deaths, time to perform the test, abnormal test
Notes
Risk of bias
Bias	Authors’ judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomised by draw of sealed envelopes.
Allocation concealment (selection bias)	Low risk	Sealed envelopes.
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	Unclear risk	Unclear - does not report any withdrawals, but not enough information to tell if results are based on the whole sample randomised
Selective reporting (reporting bias)	Unclear risk	Unclear - not clearly documented which outcomes were to be collected as part of the study
Other bias	Low risk	“These two groups were comparable for maternal ages, parities, gestational ages, modes of delivery, and Apgar scores.”