How come this doesn’t surprise me. I have had a hunch about this kind of crap since the day I was born. Marketers and business people alike will bend truths and statistics to tell what ever story fits their interests the best.
A 31 percent reduction in heart attacks, after all, seems impressive. Yet this pervasive way of describing clinical trials in medical journals—focusing on the “relative risk,” in this case of heart attack—powerfully exaggerates the benefits of drugs and other invasive therapies. What, after all, does a 31 percent relative reduction in heart attacks mean? In the case of the 1995 study, it meant that taking Pravachol every day for five years reduced the incidence of heart attacks from 7.5 percent to 5.3 percent. This indeed means that there were 31 percent fewer heart attacks in patients taking the drug. But it also means that the “absolute risk” of a heart attack for any given person dropped by only 2.2 percentage points* (from 7.5 percent to 5.3 percent). The benefit of Pravachol can be summarized as a 31 percent relative reduction in heart attacks—or a 2.2 percent absolute reduction.
This is just another example of why statistics don’t really mean much. Sure there may be cases where cold hard statistics have a meaning, but in general when someone is trying to sell you something and they offer statistics, remember, they are trying to sell you something.
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