Methods	RCT.
Participants	34 women (primigravidas and multigravidas) at 26-37 weeks’ gestation in 2 Texas hospitals (20 to supported group and 14 to usual care). They were in early, uncomplicated preterm labour
Interventions	Intervention: support provided by a Lamaze childbirth preparation instructor. Support included continuous presence, acting as a liaison with hospital staff, providing information, and teaching relaxation and breathing measures Usual care: intermittent nursing care. Family members allowed to be present
Outcomes	Fetal distress, caesarean birth, artificial oxytocin, labour length, Apgar scores, neonatal intensive care
Notes	Not stated if epidural analgesia was available or if EFM was used routinely
Risk of bias
Bias	Authors’ judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	‘Randomly assigned.’ No further details provided.
Allocation concealment (selection bias)	Unclear risk	Admitting nurse telephoned research assistant to obtain treatment allocation. No details about whether the research assistant had foreknowledge of the treatment allocation scheme
Blinding (performance bias and detection bias) All outcomes	Low risk	Medical record information collected by ‘research assistants who did not know the group membership of the women’
Incomplete outcome data (attrition bias) All outcomes	High risk	Withdrawals occurred before analysis (6 (30%) in support group and 3 (21%) in control). This resulted in a follow-up rate of 73.5%. The withdrawals were done differentially in the support group, i.e. some women were withdrawn because of an event that occurred before the support person arrived. Women in the control group with the same event were not withdrawn. We were able to re-create the original study groups for 1 outcome only, caesarean birth, and therefore it is included in the analysis table
Selective reporting (reporting bias)	Unclear risk	No outcomes were stated a priori.
Other bias	Low risk	No other sources of bias noted.