> Every day, millions of people are taking medications that will not help them. The top ten highest-grossing drugs in the United States help between 1 in 25 and 1 in 4 of the people who take them (see 'Imprecision medicine'). For some drugs, such as statins — routinely used to lower cholesterol — as few as 1 in 50 may benefit. There are even drugs that are harmful to certain ethnic groups because of the bias towards white Western participants in classical clinical trials.<p>Those are stunningly small proportions. What is the explanation? People try out lots of drugs and stop taking those that seem not to be working?<p>The graphic in the article says the proportions are related to the <a href="https://en.wikipedia.org/wiki/Number_needed_to_treat" rel="nofollow">https://en.wikipedia.org/wiki/Number_needed_to_treat</a> but I think I'll have to read that article several times to understand. :) Not clear what reference in the article (the Nature one) provides the proportions or NNT data, but the nearest footnote is paywalled anyway.