And don't forget the related metric: "number needed to harm". Physicians practicing good, Evidence-Based Medicine also weigh how many patients are likely to be

And don't forget the related metric: "number needed to harm". Physicians practicing good, Evidence-Based Medicine also weigh how many patients are likely to be impacted by harmful side effects. In an example from The NNT about PSA Screening for Prostate Cancer: http://www.thennt.com/nnt/psa-test-to-screen-for-prostate-cancer/ http://www.thennt.com/nnt/psa-test-to-screen-for-prostate-ca... No benefits were identified to PSA screening, while 1 in 5 will go on to have an unnecessary prostate biopsy (which can itself lead to complications, false-positive diagnosis, and further treatment with associated complications, and so on). (I feel obliged to mention that I'm not a doctor, btw, just sort of a casual fan of medical science and stats.)