One study shows that 30 minutes of exercise 5 times a week can reduce your risk of squamous cell carcinoma of the skin, p=0.001. (Let's pretend this is true). What does this mean?

Well, let's start by asking the question, how IMPORTANT is it that you reduce your risk of SCC of the skin, and how MUCH does exercise reduce that risk? If the effect of exercise is associated with a relative risk reduction of 1% in your lifetime risk of SCC, is that enough to get you to spend 1 week of your life each year on a treadmill?

In this week's "I wonder" series, Dr. Ali Hamedani joins Jim Siegler to discuss the difference between statistical significance and clinical importance, how to interpret p-values, and exactly what kinds of conclusions you should draw from clinical studies.

Produced by James E. Siegler and Ali Hamedani. Music courtesy of Jahzzar, Kevin McLeod, Sergey Cheremisinov, and the trio Grossman, Ewell and Grainger. Sound effects by Mike Koenig and Daniel Simion. BrainWaves' podcasts and online content are intended for medical education only and should not be used for clinical decision making. Be sure to follow us on Twitter @brainwavesaudio for the latest updates to the podcast.

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