The contribution of evidence to policy: the case of breastfeeding support and breastfeeding inequalities in England and the United States

The concept of evidence-based policy to address public health issues has increasingly been adopted in England and U.S. as the standard for policy development, with the growing expectation that systematic reviews should be the primary source of evidence. Our understanding of the relationships between evidence and policy, and systematic reviews and evidence-based policymaking is tenuous at best, yet is of fundamental importance to evidence-based policy, particularly policy to address morally and ethically-grounded issues of equity and health inequalities. It is within these relationships that the process of evidence-based policymaking and the use of systematic reviews take place. If we understand this process, we have the opportunity to control the movement of evidence into policy from inside the process itself, in order to enhance the ability of systematic reviews to contribute fully and appropriately to policy. This is the crux of the original contribution of this thesis – to get at the heart of the process of evidence-based policymaking, so that we may see where and how we can and should guide the use of evidence to address policy issues and the use of systematic reviews in evidence-based policymaking. It does so in the context of a key public health challenge in England and the U.S. – health inequalities related to nutrition, infant feeding, and policy to promote and support breastfeeding.