Culprit or correlate? An application of the Bradford Hill criteria to Vitamin E acetate.

Vitamin E acetate (VEA) has come under significant scrutiny due to its association with e-cigarette, or vaping, product use-associated lung injury (EVALI). In 1965, Sir Austin Bradford Hill proposed a set of criteria used to critically assess an association for causality. In this article, we apply the Bradford Hill causation criteria to VEA and the EVALI outbreak to clarify what further areas of study are needed to strengthen the causal argument. Additionally, we highlight the need for systematized approaches to rapidly identify the cause of mass poisoning events of unknown etiology.