Towards the dismissal of null hypothesis/statistical significance testing in public health, public law and toxicology

Null hypothesis significance testing (NHST) text was once widely popular and almost systematically used for the identification of causal relations and for risk assessment in toxicology and medicine. Interestingly, the public law world has been more prudent and more advanced than the biomedical one in the use of this dichotomous approach, based on the conventional p-value cut-points of 0.05/0.001, to assess causality. The recent 2016 statement by the American Statistical Association, the joint action by methodologists in all fields of science, and not least the seminal decisions by the US Supreme Court have highlighted the pitfalls of the dichotomous approach embedded in NHST. Overall, they also indicated the need to entirely dismiss NHST when assessing causal relations, favoring instead a more flexible and adequate approach for data analysis and interpretation. The demise of statistical significance testing would have major beneficial implications for risk assessment in toxicology, public health, and human medicine, alongside important public law implications. It could also lead to a reanalysis and re-interpretation of previous studies and bodies of evidence that may have been inaccurately assessed due to the flaws inherent in NHST.