Public health systems research: the state of the field.

Public health infrastructure provides the building blocks required for the system to achieve public health goals. A systems approach to public health has been suggested as a means to tackle persistent and emerging problems. Systems and infrastructure are attracting increased research attention. A review of the Australian and international literature suggests an absence of empirical evidence about how the system and its component parts does, or should, work and highlights some of the difficulties associated with generating such evidence. It also indicates there is significant scope for further research.