[bff]

"Evidence-based" means that you tie statistical outcomes to procedures as apposed to doing what you think might be right based on your limited life experience (which is biased).

For example, let's say there is a test that checks for a birth defect that must be treated or it will result in infant mortality. Let's also say that the test causes infant mortality one time in 10,000. Whether you perform the test has to do with the statistical likelihood that the fetus will have the birth defect - if the likelihood is less than the probability of the test killing the baby then you shouldn't do it.