Renfrew et al. (2012); various

Scale/Scope: 
varied
Evaluation Design: 
Literature review – 52 RCTs or quasi-RCTs; 37 in high-income countries, 12 in upper-middle-income countries, 2 in low-middleincome countries, and 2 in low-income countries(38)
Outcomes: 
Outcomes Measured: 
Risk of having stopped EBF at six months (all countries)
Results: 
risk ratios following all forms of extra support together: RR = 0.86
P-values/CIs: 
(95% CI: 0.82 - 0.91)
High Impact Practices: 
Exclusive breastfeeding
Outcomes Measured: 
Risk of having stopped EBF at 4-6 weeks (all countries)
Results: 
risk ratios following all forms of extra support together: RR = 0.74
P-values/CIs: 
(95% CI: 0.61 - 0.89)
High Impact Practices: 
Exclusive breastfeeding
Outcomes Measured: 
Duration of breastfeeding (all countries)
Results: 
risk ratios following all forms of extra support together: positive effect
P-values/CIs: 
--
High Impact Practices: 
Continued breastfeeding
Outcomes Measured: 
Risk of stopping breastfeeding before six months (all countries)
Results: 
risk ratios following all forms of extra support together: RR = 0.91
P-values/CIs: 
(95% CI: 0.88 - 0.96)
High Impact Practices: 
Continued breastfeeding