American Journal of Epidemiology | September 6, 2017
The contentious political climate surrounding air pollution regulations has brought some researchers and policy makers to argue that evidence of causality is necessary for more stringent regulations. Recently, an increasing number of air pollution studies purport the use of “causal analysis,” generating the impression that studies not explicitly labeled as such are merely “associational” and therefore less rigorous. Using three prominent air pollution studies as examples, we review good practices for how to critically evaluate the extent to which an air pollution study provides evidence of causality.