Carlberg M, Hardell L. Biomed Res Int. 2017;2017:9218486. doi: 10.1155/2017/9218486. Epub 2017 Mar 16. Review. Bradford Hill’s viewpoints from 1965 on association or causation were used on glioma risk and use of mobile or cordless phones. All nine viewpoints were evaluated based on epidemiology and laboratory studies. Abstract