Why should we shift into an Evidence-Based approach to patient care? I would list five reasons for this shift:

 1. New types of evidence are being generated. Over the last decade or so, an increasing number of randomized controlled trials are being undertaken to answer clinical questions. A case in point is the clinical observation that patients who suffer myocardial infarction develop some cardiac arrhythmias that sometimes could lead to death. From a pathophysiological point of view, there were some anti-arrhythmic drugs that were known to suppress such arrhythmias. So the recommendation was that post myocardial infarction patients should be treated with such anti-arrhythmic drugs based on the pathophysiologic understanding. The clinical question that needs to be answered is "Does such anti-arrhythmic therapy reduce post myocardial infarction mortality?" So, a randomized controlled trial was undertaken to try to answer this question. The result was astonishing in that it showed that the treatment group had a higher mortality rate, compared to the placebo group. It is obvious, then, that understanding of pathophysiology alone is not sufficient to dictate a clinical practice. Medical intervention (drug interventions or non-drug interventions) has to be tested through randomized controlled trials. Increasing use of a statistical manipulation of multiple trials that are pooled and subjected to some statistical analysis called meta-analysis or overviews, lead to new types of evidences. It goes without saying that, with the availability of this type of new evidences, major changes in patient care would need to be undertaken.