Bahadoran 2011.

Methods	Randomised controlled trial.
Participants	Inclusion: gestational age > 36 weeks, physician‐prescribed induction, age of 18 to 35 years, pre‐pregnancy BMI < 26, singleton fetus with vertex presentation and anterior oxiput, a Bishop score > 5, no use of medicine other than painkillers and antibiotics, no use of prostaglandins or other induction methods, no placenta abruption, and correct heart rate pattern. Exclusion (after randomisation): hypertonic uterus, fetal distress prior to the intervention, allergy towards the study medication, insufficient progression (< 0.5 cm cervical dilatation/hour). Setting: Iranian University Hospitals, April 2009 to September 2009 (period of inclusion). Number of included participants: 60 continued and 60 discontinued oxytocin, 10 women were excluded after inclusion. The paper contains no CONSORT flow diagram. Participants were recruited at induction but the randomisation envelopes were not opened until the in active phase (4 cm or 5 cm). It is not noted if envelopes were returned unopened if labour proceeded to rapidly to allow opening or if caesarean was done before the active phase. According to the text, 5 individuals in each group Quote: "exited from the study due to lack of progression". However, both results tables 2 and 3 include only 50 individuals in the control group and 54 in the experimental one. This suggests the 10 and 6, respectively exited.
Interventions	Oxytocin + ringer serum. Ringer serum. 5 units of oxytocin in 500 cc ringer serum. Starting dose 6 mU/minute and then increased every 30 minute by 6 mU until effective labour contractions were achieved. No available information on maximal dosage.
Outcomes	Primary Duration of first stage of labour Secondary Duration of second and third stages of labour, oxytocin dosage Neither mode of delivery, nor any clinical outcomes were reported
Notes	Trial funding: no information. The trial was not registered. Trial authors reported no conflicts of interest.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Table of random numbers.
Allocation concealment (selection bias)	Unclear risk	Closed envelopes but the lack of consort flow diagram makes judging participant flow difficult. Envelopes were not reported to be numbered and there was no statement about missing envelopes. Not clear if unopened envelopes were returned to the sequence.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	The shift supervisor opened the envelope, prepared the infusion and replaced the oxytocin drip with either placebo or a new oxytocin drip. Only the shift supervisor was aware of the assigned intervention.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Outcome assessments were performed by 3 persons using a validated tool for evaluating the stages. The duration of the various stages of labour is subjective. Randomisation to birth interval, which would be unbiased, was not reported.
Incomplete outcome data (attrition bias) All outcomes	High risk	No information of the number of eligible women. Outcome data were missing for 10/120 women (8.3%). No flow diagram was included.
Selective reporting (reporting bias)	High risk	No protocol was published prior to article. No clinical outcomes were reported.
Other bias	High risk	Randomisation was performed when oxytocin infusion was initiated and not when continued or discontinued, and there was no Consort flow diagram.