About That Finding… | The Daily Scan | GenomeWeb

About That Finding… | The Daily Scan | GenomeWeb


"Medical studies that show large effects often don't hold up under further scrutiny, a new paper published in the Journal of the American Medical Association says. Stanford University's John Ioannidis and his colleagues analyzed clinical trial data from the Cochrane Database of Systematic Reviews and found that "when additional evidence is obtained, most of the very large treatment effects become much smaller and many lose their nominal significance," the authors write.
Ioannidis and his colleagues add that while there are some truly large, well-established effect sizes seen in medical studies, they are quite rare and don't usually affect mortality.....