Guide for Evidence-Based Medicine (4) : Approach to the Evaluation of Medical Treatment

We often hear about evidence-based medicine (EBM) in medical journals or speeches at conferences. When you read about EBM and try to practice it, you may encounter some difficult terms such as "critical appraisal" or "relative risk". When you see statistical expressions, many of you may ever give up. In the 1999 clinical clerkship for 6th year medical students, we make sure you can acquire the skills in technical concepts and terminology defined through work sheets, which we have reported and associated with the Users\u27 Guide series published in the Journal of the American Medical Association. By using these sheets, you can systematically check through the validity, importance, and ways to adapt them to your actual patient. As a definite plan, we chose the WOS (West of Scotland) study conducted by Shepherd et al well-known as the primary prevention study for hypercholesterolemia. At first, for the evaluation of validity, you should check the following: if the study is a randomized controlled trial, how were endpoints defined? Second, you should evaluate the importance of the results using relative risk (RR), relative risk reduction (RRR) and the number needed to treat (NNT). Finally you should investigate how your actual patient can be adapted to the process. It will be an important skill for clinicians in the future to acquire the skill of EBM. However, we recognize that the well being of patients supersedes any recommendations we make through EBM. Still, it is necessary for medical experts to continue to look for evidence that does not rely solely on our experience or impression