Systems science, implementation science, and public health programs

Public health is concerned with studying the health outcomes of groups, including the distribution of health outcomes within these groups. Our dominant methodologic approach in public health has yielded substantial public health success. There is, however, a growing appreciation of the challenges of this approach, particularly as we recognize the need to address multiple factors within complex system frameworks in order to improve health. This chapter discusses: what complex systems are, and how the work of public health has to be concerned with complex systems; how to construct a logic model that can describe the complex problem that requires public health action; examples of how the application of complex system approaches can help improve the health of the public; implementation science and what is needed to implement successful interventions in public health; and the link between healthcare systems and public health in the United States and worldwide.