Johnson 1985.

Methods	RCT. Sequence based on a random number table. No details were given on the method for concealment of the allocation.
Participants	Term, primiparas, BS < 6.
Interventions	Lamicel (40 women); PGE2 vaginal gel (4 mg) (40 women).
Outcomes	Epidural analgesia, CS, instrumental delivery, uterine hyperstimulation, fetal distress.
Notes	Setting: UK Dates of study: not reported Funding: not reported Declarations of interest: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Random number table
Allocation concealment (selection bias)	Unclear risk	Not reported
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	Unclear risk	ITT unclear, no missing cases or data
Selective reporting (reporting bias)	Low risk	All pre‐specified outcomes reported
Other bias	Low risk	No other bias detected