Sullivan 1996.

Study characteristics
Methods	RCT. Concealment of allocation by opaque, sealed envelopes.
Participants	BS < 6 and indication/no contraindication for IOL.
Interventions	Intracervical PGE2 (0.5 mg) and Foley catheter inflated with 50 mL of water (41 women); intracervical PGE2 (0.5 mg) repeated after 4 to 6 hours if needed (37 women).
Outcomes	CS, uterine hyperstimulation with and without FHR changes, infection.
Notes	Setting: Jackson, USA Study period: October 1993 ‐ May 1994 Funding: supported by the Vicksburg hospital medical foundation Declarations of interest: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not reported
Allocation concealment (selection bias)	Low risk	Concealment of allocation by opaque, sealed envelopes.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Not feasible due to nature of intervention
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not reported
Incomplete outcome data (attrition bias) All outcomes	Low risk	ITT not reported, but is reasonable as numbers are equal to randomised numbers, no missing cases or data
Selective reporting (reporting bias)	Low risk	All pre‐specified outcome reported.
Other bias	Low risk	No other bias detected