Evidence based medicine, using randomized controlled trials and meta-analyses as the
major tools and sources of evidence about average results for heterogeneous groups of
patients, developed as a reaction against poorly designed observational treatment research
and physician reliance on personal experience with other patients as a guide to decision-
making about a patient at hand. However, these tools do not answer the clinician's
question:“Will a given therapeutic regimen help my patient at a given point in her/his clinical …

Medical practice is changing due to the more efficient use of the biomedical literature in
making decisions on the care of individual patients. This constitutes a new scientific
paradigm: evidence-based medicine (EBM). The factors that may explain the growing
interest in EBM are awareness of variability in clinical practice, the importance of the
efficacy, effectiveness and efficiency of new health technologies, and ease of access to
biomedical literature (especially through the Internet). The main tools of EBM in clinical …