Take a look at these two blogs on evidence-based practice, Bob Sutton’s Work Matters and Tracy Allison Altman’s Evidence Soup.
Bob Sutton is a professor of management science and engineering at Stanford. He writes about Evidence Soup, “Reading Altman’s blog is like taking an ongoing course in how to make evidence-based decisions and how to take – and evaluate – evidence based actions.”
I have previously mentioned Bob Sutton as the co-author of Hard Facts, Dangerous Half-Truths And Total Nonsense: Profiting From Evidence-Based Management.
Read e.g. his Management Advice: Which 90% is Crap? (this is a reference to John Wanamaker’s statement that 50% of the money he spent on advertising was wasted, but he didn’t know which 50%).