hill's criteria

The media just handed fluoride conspiracy theorists a gift on a giant silver platter: Multiple outlets are reporting that pregnant women who consume too much fluoride produce children with lower IQs. The reports are based on an extremely controversial study just published in JAMA Pediatrics. Are the study's conclusions true? It's doubtful.
In a 1965 address, epidemiologist Austin Bradford Hill introduced nine criteria that researchers should consider before declaring that A causes B. Here's a concise summary of his presentation.