To see why the difference between t

To see why the difference between the two ways of expressing risk matters,let's consider the hypothetical example of a drug that reduces heart attack risk by 40%.Imagine that out of a group of 1000 people who didn't take the new drug,10 would have heart attacks.The absolute risk is 10 out of 1000,or 1%. If a similar group of 1000 people did take the drug,the number of heart attacks would be six.In other words,the drug could prevent four out of ten heart attacks——a relative risk reduction of 40%.Meanwhile,the absolute risk only dropped from 1% to 0.6%——but the 40% relative risk decrease sounds a lot more significant.