Haghighi 2013.

Methods	A randomised double‐blind clinical trial, conducted between January 2009 and November 2010, in Shahid Akbar‐abadi Obstetrics and Gynaecology Centre, a University hospital in Tehran, Iran.
Participants	136 women scheduled for induction pf labour were recruited for the study. Inclusion criteria: primiparous, singleton, term or post‐term pregnant women with Bishop score < 5 and cephalic presentation were included in the study. Exclusion criteria: EFW > 4 kg, oligohydramnios, IUGR, non reassuring FHR, ruptured membranes, any contraindication to prostaglandins or ISDN, BMI > 30, placenta praevia, vaginal bleeding, uterine contractions, suspected chorioamnionitis.
Interventions	132 participants were randomly assigned to either misoprostol group or ISDN. 64 in misoprostol group and 66 in ISDN group. 2 women in misoprostol group had caesarean section on request and hence were excluded. Women in misoprostol group had 25 mcg PGE1 and women in ISDN group had 40 mg ISDN, maximum of 2 doses were inserted vaginally after 4 hours if the Bishop score was < 8 or uterine contractions < 3 in 10 min with duration of < 40 seconds.
Outcomes	Maternal: changes in Bishop score after the drug administration, need for stimulation, time from initial dose to active phase of labour and to delivery, method of delivery, complications of ISDN. Fetal: 1 and 5 min Apgar score < 7.
Notes	After 2 doses of the drug, oxytocin was used and women had caesarean section delivery if labour not established 6 hours after oxytocin infusion.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Block randomisation.
Allocation concealment (selection bias)	Low risk	Numbered sealed opaque envelopes were used.
Incomplete outcome data (attrition bias) All outcomes	Low risk	The study drop outs were explained and participants were analysed in their respective groups.
Selective reporting (reporting bias)	Low risk	No evidence to the contrary.
Other bias	Low risk	No evidence to the contrary.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Double‐blind trial.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Double‐blind trial.