Caliskan 2002

Methods	4‐arm active‐controlled double‐dummy randomised trial.
Participants	Between 1st January 2000 and 1st October 2000,1633 parturients were randomised in a hospital setting in Turkey. The population comprised women of unspecified parity, either singleton or multiple pregnancy, at both high and low risk for PPH, who delivered by vaginal delivery. Exclusion criteria comprised parturients undergoing caesarean section, or those with gestational age less than 32 weeks or hypersensitivity to prostaglandins.
Interventions	400 mcg plus 10 IU of misoprostol plus oxytocin administered rectally plus by an intravenous infusion (n = 407) versus 400 mcg of misoprostol administered rectally (n = 405) versus 10 IU of oxytocin administered by an intravenous infusion (n = 412) versus 200 mcg plus 10 IU of ergometrine plus oxytocin administered intramuscularly plus by an intravenous infusion (n = 409).
Outcomes	The study recorded the following outcomes: PPH at 500. PPH at 1000, additional uterotonics, transfusion, change in Hb level, third‐stage duration (min), vomiting, fever, shivering.
Notes	Contact with study authors for additional information: yes. Additional data from authors: no.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomisation was based on a table of computer‐generated blocks of random numbers.
Allocation concealment (selection bias)	Low risk	Investigators used sealed consecutively‐numbered opaque envelopes.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	"All medications were applied by midwives, but residents who treat[ed] the birth and the third stage of labour were blinded to the identity of medication. Only the midwife who applied the medication opened the envelope once to read the code and then transferred the randomisation code into another identical envelope. The identities of the placebo and active medication were also concealed from caregivers and residents who followed the patient for the next 24 hours. The randomisation code was not broken until study completion."
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"All medications were applied by midwives, but residents who treat[ed] the birth and the third stage of labour were blinded to the identity of medication. Only the midwife who applied the medication opened the envelope once to read the code and then transferred the randomisation code into another identical envelope. The identities of the placebo and active medication were also concealed from caregivers and residents who followed the patient for the next 24 hours. The randomisation code was not broken until study completion."
Objective assessment of blood loss	Low risk	Investigators evaluated blood loss by collection with a sterile steel bedpan and plastic bed linen. Gauzes and pads were also collected and weighed until 1 hour after delivery of the placenta.
Incomplete outcome data (attrition bias) All outcomes	Low risk	"The study enrolled 1633 women, but the data for 27 women were excluded because of lack of predelivery (n = 13) or postpartum (n = 14, short hospital stay) haemoglobin concentrations."
Selective reporting (reporting bias)	Unclear risk	The protocol of the study was unavailable for verification.
Intention to treat analysis	High risk	Those who withdrew from the study after randomisation were not included in the analysis.
Funding source	Unclear risk	Source(s) of funding for the study were not reported.