Sosa 1976b.

Methods	Randomized controlled trial (random numbers in sealed envelopes).
Participants	68 healthy full‐term infants and their mothers randomized immediately after delivery.
Interventions	1) Experimental group = mothers held their infants in SSC for 45 min after the episiotomy repair. They were encouraged to breast feed. 2) Control group = infants were separated from their mothers for 12 hours.
Outcomes	1) Mean duration of breastfeeding. 2) Episodes of illness, growth and development, mortality.
Notes	Study was done with poor, urban primipara from the marginal area of Guatemala city in 1976. We have reported on results for the Roosevelt 2 study as Sosa 1976b. All women had episiotomy (hospital routine for primiparous women). No woman had analgesia during labor. The socio‐economic index in the control group was 14 and it was 12 in the experimental group so the control group had a slightly higher socio‐economic status than the experimental group.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	“Assignment of mother‐infant pairs.... was made from random numbers..”
Allocation concealment (selection bias)	Unclear risk	Allocations were concealed in sealed envelopes which were opened immediately after delivery.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Not possible to blind. Mothers would be aware of allocation, staff were also likely to have been aware of treatment group and may have altered other aspects of treatment.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Blinding of outcome assessors is not mentioned, apart from blinding of researchers for behavior outcomes measured in a different population in a 3‐armed investigation of maternal bonding. For this study staff were likely to have been aware of treatment group and may have altered other aspects of treatment.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	68 women. Denominators for longer‐tem outcomes were not specified so it is not clear how many women remained available to follow‐up at each data collection point.
Selective reporting (reporting bias)	High risk	No SD reported with mean breastfeeding duration. No systematic reporting of longer‐term outcomes for all trials collected at 3, 6, 9 and 12 months.
Other bias	Unclear risk	It is not clear whether any women were still breastfeeding at the final data collection point. We were unsure of the impact of differences in socio‐economic status between treatment arms. For this trial, women had higher socio‐economic status in the control group.