While there is widespread understanding that the health system and other factors — social determinants — affect health, we know relatively little about their precise contributions to health differences across a population at a point in time or differences in health of a fixed population over time.
A common way to assess how much various factors contribute to health is to estimate how much variation in health across the country is explained by each of those factors. But explaining variation is not as useful as many may think.
I wrote about Nancy Krieger’s insightful American Journal of Public Health paper in a previous post. In this second of three posts, I will continue to unpack some of the content of her article, focusing on the distinction between correlation and causation.
In 2017, Nancy Krieger, Professor of Social Epidemiology at the Harvard T.H. Chan School of Public Health, published a truly insightful paper in the American Journal of Public Health in which she raised several conceptual problems with allocating health outcomes to contributions from risk factors.