I’ve written in the past about the Number Needed to Treat (NNT). I think it’s one of the most important metrics we have in medicine to determine the efficacy of a modern medical intervention at the population level. I would even suggest that drugs should be approved by the FDA based on the NNT. And today, a group of three doctors launched an amazing new site that publishes this very often hard to access data. Here are the numbers for statins (like Lipitor, the best selling drug in America at a cost of $115 per month per person) from their site:

In Summary, for those who take the statin for 5 years:

• 98% will see no benefit
• 0% will be helped by being saved from death
• 1.6% will be helped by preventing a heart attack
• 0.4% will be helped by preventing a stroke
• 0.6% will be harmed by developing diabetes*

In Other Words:

• None will be helped (life saved)
• 1 in 60 will be helped (preventing heart attack)
• 1 in 268 will be helped (preventing stroke)
• 1 in 167 will be harmed (develop diabetes*)