Ngai 1996.

Methods	Randomisation was by the sealed envelope method. The stratification was by parity (nulliparas, multiparas).
Participants	82 women with a singleton pregnancy at term and prelabour spontaneous rupture of membranes confirmed by speculum examination. All women had a reactive non‐stress test on admission.
Interventions	200 mcg oral misoprostol powder or placebo (vitamin B6). If no response after 12 hours labour was induced with oxytocin.
Outcomes	Changes in the BS, need for oxytocin for induction, interval from recruitment to onset of uterine activity and delivery, mode of delivery, neonatal outcome.
Notes	2 women excluded from the primary analysis (one breech and one without baseline cervical assessment).
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Stratified randomisation between multipara and nullipara
Allocation concealment (selection bias)	Low risk	Each patient was given an envelope, chosen according to the stratified randomisation between multiparas and nulliparas
Incomplete outcome data (attrition bias) All outcomes	Low risk	Data for all women reported
Selective reporting (reporting bias)	Low risk	Selective reporting not apparent
Other bias	Low risk	None noted
Blinding of participants and personnel (performance bias) All outcomes	Low risk	The envelopes were coded by the hospital pharmacy and the codes were broken only at the end of the study, so that both the medical staff and the patient were blinded to assignment
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Blinding of outcome assessor not described