Boulvain 1998.

Methods	Randomised controlled clinical trial
Participants	Setting: 3 tertiary care hospitals of the province of Quebec, Canada. Page 35 Duration of study: 17 months(1 April 1995 to 1 October 1996). Page 35 Inclusion criteria: included if eligible for a “non‐urgent medical indication for induction of labour and a single fetus in cephalic presentation. Non‐urgent medical indication for induction included: post‐term pregnancy, hypertension, diabetes, fetal growth retardation without signs of fetal distress, or other medical complications of pregnancy. Post‐term pregnancy was defined as gestational age > 287 days when formal induction of labour was scheduled”. ‘Only women at term (≥ 266 days) were included in the trial’. Written informed consent must have been obtained. Gestational age was calculated from the last menstrual period and an ultrasound examination carried out in the middle trimester. Induction date between 3 and 7 days after randomisation. A date for formal induction of labour was given prior to randomisation, at least 3 days and not later than 1 week after inclusion. Page 35 Exclusion criteria: “Women presenting with placenta praevia, abnormal cervical discharge, or contraindications to vaginal delivery were excluded.” Page 35 Parity: mixed, both nulliparous and multiparous women included. Page 36 (Table 1) Bishop score: recorded (not available for 2 women, 1 in each group) Page 36 (Table 1)
Interventions	Membrane stripping (n = 99): “examination began with assessment of the Bishop score, followed by the intervention. Physicians were requested to report the characteristics of the cervix (dilatation 0‐3 points effacement 0‐3, station 0‐3, consistency 0‐2, position 0‐2) before performing the intervention’˜. Sweeping of the membranes consisted in circular movements of the examining finger between the lower segment of the uterus and the fetal membranes. When the membranes could not be reached, physicians were requested to attempt to gently dilate the cervix. If this manoeuvre was successful, sweeping was performed. If the cervix acted as a barrier to the examining finger, cervical massage was performed” Page 35 Control group (n = 99): women in the control group had only a vaginal examination for Bishop scoring. Page 35
Outcomes	Epidural Spontaneous vaginal delivery Forceps/vacuum delivery Caesarean section Apgar ≤ 7 at 5 minutes Neonaltal infection Neonatal convulsions Formal induction of labour Evaluation of pain during examination: VAS (n = 87‐87) PPI (n = 94‐92) labour agentry scale (n = 90‐85)
Notes	Funding: study was supported by grant number 6605‐4645‐ 401 of NHRDP, Health Canada. Dr Boulvain received salary support from Astra Pharma. Dr Fraser receives salary support from the Medical Research Council of Canada. Dr Marcoux holds a Health Research Scholarship from Health Canada. Page 39 Trial authors’ declaration of interest: none stated. Informed consent obtained: yes Page 35 Ethical approval: not stated
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	“computer generated list of random numbers, with randomly permuted blocks of six and eight, stratified by hospital” Page 35.
Allocation concealment (selection bias)	Low risk	“the allocations were contained in a series of opaque, sealed and consecutively numbered envelopes, kept in the delivery unit” “clerk opened the next envelope and informed the doctor of the woman’s allocation” Page 35
Blinding of participants and personnel (performance bias) All outcomes	High risk	Participants: unclear if women blinded. Personnel: clinician not blinded Page 35
Blinding of outcome assessment (detection bias) All outcomes	Low risk	“Obstetric data were abstracted from the hospital charts by a research assistant who was unaware of the treatment allocation”. Page 36.
Incomplete outcome data (attrition bias) All outcomes	Low risk	The analysis was based on “Intention to treat”. However it was noted that “Two women in the control group were excluded after randomisation: one withdrew her consent and the other failed to meet the main inclusion criteria in that she was not scheduled for induction of labour” Page 36
Selective reporting (reporting bias)	Low risk	No selective reporting bias noted.
Other bias	Low risk	No other bias noted.