[From evidence to practice: a difficult but not impossible itinerary]

In recent years, evidence-based medicine (EBM) has acquired its own dignity and cultural identity, and increasing importance. EBM helps doctors understand that the uncertainties of medicine must be analyzed quantitatively in order to rationalize and systematize the information gathered from clinical observation; on the other hand, it provides them with suitable instruments to estimate the performance of diagnostic tests and the efficacy of drugs. One of the main merits of EBM has been the progressive spread of randomized controlled trials as the gold standard for evaluating the effectiveness of treatments. EBM's primary objectives can be summarized by the following points: 1) To transform the physicians' need for information into questions that may be answered (ie, formulate the questions); 2) To find in an as efficient way as possible the best evidence to answer these questions; 3) To critically evaluate the evidence obtained (ie, assign a weight to it) in order to determine its validity (ie, its approximation to the truth) and its usefulness (ie, its concrete clinical applicability); 4) To introduce into clinical practice the conclusions drawn from the results; 5) To estimate individual physicians' performance (ie, one's own conduct and efficiency). EBM's advantages are not only that physicians have acquired a method to search for the right evidence and to apply diagnostic and therapeutic procedures, but, more importantly, that it has provided them with the only tool for true quality improvement, namely the critical appraisal of their own work. Unfortunately, the latter is too often based on a different type of EBM: Evidence-Based Medicine.