Attilakos 2010

Methods	2‐arm active‐controlled double‐blinded randomised trial.
Participants	Between November 2006 and July 2007, 377 parturients were randomised in a hospital setting in the UK. The population comprised women of unspecified parity, a singleton pregnancy, at high risk for PPH, who delivered by either elective or emergency caesarean. Exclusion criteria comprised parturients undergoing caesarean section with general anaesthesia, gestational age less than 37 weeks performed for fetal or maternal distress where, due to time constraints, it was not possible to recruit or randomise, or those with multiple pregnancy, placenta praevia or placental abruption.
Interventions	100 mcg of carbetocin administered by an intravenous bolus (n = 188) versus 5 IU of oxytocin administered by an intravenous bolus (n = 189).
Outcomes	The study recorded the following outcomes: PPH at 1000, morbidity,. additional uterotonics, transfusion, death, blood loss (mL), change in Hb level, nausea, vomiting, headache, tachycardia, hypotension, shivering, abdominal pain.
Notes	Contact with study authors for additional information: yes. Additional data from authors: yes.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	The randomisation sequence (1:1 ratio—blocks of 10, no stratification) was generated by computer.
Allocation concealment (selection bias)	Low risk	The preparation of the ampoules was undertaken by DHP Ltd. (Powys, UK) which provided sequentially numbered and labelled boxes each containing a 1 mL ampoule of the study drug. All boxes and ampoules were identically labelled, with the study number being the only differentiating feature between different drug packs. The random allocation sequence was not known to the investigators until the study had finished and the analysis was started.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Study participants and caregivers were blinded to treatment allocations.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Assessors were blinded to treatment allocations.
Objective assessment of blood loss	High risk	Blood loss was estimated by the attending surgeon "in the usual way (visual estimation, number of used swabs and amount of aspirated blood)."
Incomplete outcome data (attrition bias) All outcomes	Low risk	Data were collected completely from all randomised study participants.
Selective reporting (reporting bias)	Low risk	The study report matches the study protocol that was registered prospectively (EudraCT 2005‐002812‐94).
Intention to treat analysis	Low risk	All those who were enrolled and randomly allocated to treatment were included in the analysis, in the groups to which they were randomised.
Funding source	Low risk	Ferring Pharmaceuticals funded the cost of preparation of blinded medication ampoules. No other external funding was required for the study.