Writing in the Boston Globe, Neena Satija offer some useful advice about the risk of taking the word "risk," as used in scientific studies, too seriously. Looking first at the reduction of the risk of heart disease touted in a recent study of chocolate eaters, Satija points out that the much-hyped study, conducted by University of Cambridge researchers, was actually the result of reviewing seven separate studies of the topic. One of those studies found that the combined risk of heart attack and stroke for those who ate the most chocolate was 39 percent lower than those who ate the least. That’s one way of stating it. Here's another way: For those who ate the most chocolate, researchers documented 2.72 cases of heart attack or stroke per 1,000 people per year, or .272 percent – the modified risk. For those who ate the least, there were 1.44 cases per 1,000 people per year, or .144 percent – the starting risk. Satija next reports on the clinical trial of a new drug for a viral disease, which was shown to reduce the risk of dying from the disease by 33 percent, or one-third. What that means is this: Out of all patients who were given the new drug, 96 percent survived and 4 percent died. For those on the old drug, 94 percent survived and 6 percent died. So, the mortality rate decreased by one-third – from 6 percent to 4 percent. Confusing, isn't it?
What's a consumer to do? Satija suggests that the next time you read about a study that says taking a certain medication increases your risk of having a heart attack, for instance, ask the following questions:
â– What’s the risk of having a heart attack for the people who took a placebo – the “control population’’?
■What’s the risk of having a heart attack for those treated with the medication being studied?
â– How big is that difference? Is it significant?
■What kind of people are being studied? Do their characteristics fit you? If all the study participants are heavy smokers, for instance, and you have never smoked, the study’s results likely do not apply to you.
â– What does the study outcome measure? For instance, did it follow people for five years to see if they had a heart attack after taking a certain medication? Or only for one year?
â– Are there any potential benefits to taking the medication that might outweigh the risks presented by the study?
It appears the Satija reversed the numbers regarding the risk in the chocolate study.
The article is interesting, but does not really change the fact that the risk has indeed been reduced by 33% ragardless of the fact that only a very small percentage of the general population will develop the desease.
Of course then you must weigh increased risk from the weight gain from eating all the chocolate…