Learning and knowledge-production for public health: a review of approaches to evidence-based public health.

Public health needs to be evidence-based if it is to be done correctly, which means that learning and knowledge-production for public health must be comprehensive and include knowledge from four different domains: distribution of health, determinants or causal web, consequences, and intervention methods. Specification of development trends in cardiovascular prevention points at four generations of preventive programs; these include a clinical, a bioepidemiological, a socioepidemiological, and an environmental and policy-oriented generation. Generations differ in focus and strategy, in knowledge base--the art of making an impact--and evaluation. Comprehensive public health programs often comprise components from different generations, leading to the need for an expanded model for research and evaluation. There is an urgent need for learning and knowledge-production using both quantitative and qualitative approaches for developing the evidence base for public health action. In addition, epidemiological knowledge is necessary for making appropriate priorities.