Methods	RCT.
Participants	212 nulliparous women in active labour at term (105 support group, 107 control group) at a University-affiliated hospital in Sao Paulo, Brazil. To be eligible a companion of the woman’s choosing had to be available. 49.5% of the companions were present at enrolment and the others were phoned and asked to come to the hospital (4 failed to make it before delivery)
Interventions	Support was ‘presence of a chosen companion during labour and delivery’. ‘The companions received verbal and written information on the activities involved in providing support, expected behaviour when confronted with signs of tiredness, anxiety, concern, crying, screaming and/or the woman’s feelings of inability to cope, compliance with regulations and the possibility of requesting information from staff’. in 47.6% of the sample the woman’s companion was her partner, for 29.5% it was her mother The control group received usual care where a companion during labour and delivery was not permitted For both groups labour and delivery care was provided ‘according to the routine protocol including active management of labour (early amniotomy, use of oxytocin, intermittent EFM and systematic analgesia)’
Outcomes	Satisfaction with labour and delivery, perinatal and breastfeeding outcome in the 12 hours post delivery
Notes	All women in labour at this hospital received epidural analgesia as a routine practice. Therefore, we did not include epidural analgesia data in the review EFM was not used routinely.
Risk of bias
Bias	Authors’ judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	‘Computer generated sequence of random numbers.’
Allocation concealment (selection bias)	High risk	‘Individual assignment numbers were all placed in an opaque container to assure the concealment. The eligible women who had agreed to participate selected one of the numbers once, and were therefore allocated to either intervention group or control according to the list.’ This process was open to selection bias as women could have repicked another number from the container. No audit process is possible with this system of randomisation
Blinding (performance bias and detection bias) All outcomes	High risk	Data collection by author, who knew group allocation.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Medical record data were collected and in-hospital questionnaires were completed for 100% of sample
Selective reporting (reporting bias)	Low risk	All outcomes were reported.
Other bias	Low risk	No other sources of bias noted.