Sawai 1994.

Methods	Randomised by computer‐generated lists. Concealment unclear.
Participants	91 women requiring induction of labour. Inclusion criteria: BS < 9. Exclusion criteria: maternal medical problems, previous uterine surgery, previous stillbirth, abnormal FHR, vaginal bleeding, SROM, regular uterine contractions, abnormal ultrasound findings, fetal weight > 4500 g, non‐reactive NST.
Interventions	2 mg PGE2 vaginal suppositories (n = 38) or identical placebo (n = 42) daily (outpatient administration). Twice‐weekly assessments until 44 weeks.
Outcomes	Spontaneous labour, SROM, number of suppositories used, oxytocin use, mode of delivery, Apgar scores, umbilical artery pH, presence of meconium, NICU admission.
Notes	University of South Florida College of Medicine, USA.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomised by computer‐generated lists.
Allocation concealment (selection bias)	Unclear risk	Method of allocation concealment not reported.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	No blinding but identical placebo used.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	No blinding.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	No randomised patients lost to follow‐up.
Selective reporting (reporting bias)	Unclear risk	Unclear which outcomes prespecified.
Other bias	Unclear risk	Small, single centre RCT, source of funding for trial not clear.