The 68th annual meeting of the American Psychosomatic Society got underway today with several presentations of interest.  First was a lecture that ties in with my recent blogs on assessing medical evidence.  The speaker presented studies that showed that people who took Vitamin E supplements for at least two years were about 40% less likely to suffer heart disease.  The researchers were well aware that people who take supplements are less likely to smoke and probably take better care of themselves in general.  So they attempted to account for those factors in every way they could using statistical techniques.  This gave their results enough credibility that they received wide attention from news media.  However, when this issue was studied using a PCRT (placebo-controlled randomized trial), which is a much more reliable method, the Vitamin E made no difference.  The speaker’s point was to be skeptical of results from population surveys because it is nearly impossible to account for all confounding factors.  He went on to talk about using genetic markers to make those surveys more reliable and accurate.

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