Salmanian 2012.

Methods	Randomised controlled trial
Participants	Setting: Islamic Republic of Iran. Duration of study: not reported. Participants randomised: N = 60 Inclusion criteria: “pregnant women (gestational age >40w), primigravida and gravida 2” other inclusion criteria not reported (Page S811). Exclusion criteria: not reported. Parity: mixed. Both nulliparous and multiparous women included (primigravida and gravida 2), however no data provided (Page S811). Bishop Score: mean of Bishop score change recorded only. Baseline and final Bishop scores not recorded (Page S811).
Interventions	Group A (N = not reported): membrane stripping Group B (N = not reported): PGE2
Outcomes	Data supports subgroup analysis only
Notes	Funding: none declared Trial authors’ declaration of interest: none declared Informed consent obtained: not stated Ethical approval: not stated Email sent 5 June 2017 requesting further data. Email sent 28 September 2017 requesting further details. No reply to date.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not reported.
Allocation concealment (selection bias)	Unclear risk	Not reported.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Participants: not blinded. Personnel: unclear.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not reported.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Attrition not reported.
Selective reporting (reporting bias)	Unclear risk	No protocol available. Conference abstract only.
Other bias	Low risk	No protocol available, conference abstract only. However, no other bias noted.