Evidence-based medicine

Evidence-based medicine can be defined as the well-conceived and beneficial use of current research knowledge in making decisions concerning patient care.  The concept of evidence-based medicine has two fundamental principles, it is based on best available research studies and the subsequent transfer of their results to use in practice.  It follows that an evidence-based approach has several advantages. Patients are better served because only tested procedures will be endorsed. The standing of the profession will be enhanced because only proven treatments will be offered.
Evidence hierarchies classify the importance and robustness of diverse types of biomedical research. There is no universally accepted hierarchy of evidence, though there is broad agreement on the relative strength of the principal types of research, or epidemiological studies. Randomized controlled trials (RCTs) rank above observational studies, while expert opinion and anecdotal experience are ranked at the bottom. Nonetheless, RCTs are not always the ‘ideal’ way of conducting clinical research. The “ladder of evidence” was developed, to a large extent, for questions related to interventions or therapies. For questions related to the cause, diagnosis or prognosis of a disease, cohort studies or case-control studies will often be more appropriate. It is useful to think of the various study designs, not as a hierarchy but as categories of evidence which will allow the strongest possible, practical and ethical study-design to be chosen.[More]