Chris Schmid is a statistician at New England Medical Center who is an expert on evidence-based medicine. I invited him to present an introductory overview lecture on the topic at last year's Joint Statistical Meetings, and here are his slides. All 123 of them. I don’t know how he expected to go though all of these in an hour. You could teach a semester-long course based on this material.
Good stuff, I recommend you all read it.
I'm posting this here because (a) medicine is important in its own right, and (b) the principles of evidence-based medicine also apply to public policy.