Epidemiology and health policy: How to avoid becoming prisoner of the proximate

Abstract

It goes without saying, epidemiology –the science of distribution of diseases and risk factors in popula-tions–isthebasisforallsoundandrationalhealthpolicy.Politiciansandpeopleinchargeof healthservices will always be looking for data on the needs for health care in the population, particularly in a welfare state where health services are supposed to be provided according to medical needs and not according to wealth, or “demands” in the market. However, there are two obvious challenges for epidemiology in this respect: 1. It must provide evidence relevant to population health and health policy, and 2. Since health policy is also about health promotion and the prevention of disease, knowledge derived from epidemiology needs some extra concerns and considerations: Epidemiological knowledge is based on data from individuals, while sound preventive measures require strategies for populations. This shift in perspective calls for a good understanding of “causes of the causes”, the social determinants for health. There is a risk of being seduced by “the inverse evidence law”, suggesting that the best evidence we have is about the simplest but poten-tially least effective interventions. We have less, or weaker evidence about complex interventions –such as policies. This paradox may lead to the false conclusions that lack of evidence means that there is evidence against an intervention. A true challenge for epidemiology, when providing evidence for health policy, is how to avoid becoming “prisoners of the proximate”.