Over the last five years the adjective ‘evidence-based’ has become difficult to avoid. Indeed, a MEDLINE search for articles containing the phrase ‘evidence-based medicine’ in their titles or abstracts reveals one mention in 1992, rapidly increasing to 53 in 1996. So great has been the increase that the National Library of Medicine now includes ‘evidence-based medicine’ as a MeSH heading for indexing papers.

But what is evidence-based medicine (EBM)? First and foremost, EBM is a set of strategies designed to help the clinician keep up-to-date and to base his clinical decision making on the best available external evidence. EBM has been espoused by policymakers, purchasers and others — and, although the approach is open to misuse by these groups as a cost-cutting exercise, there are refreshing signs that they will be able to use the approach to help produce real improvements in patient care. However, the essential focus of EBM is on assisting doctors and other clinicians make decisions about individual patients. The steps involved in EBM include: a precise definition of the clinical problem (a crucial first step — in medical practice it will usually include making a diagnosis), an efficient search for the best available evidence, critical appraisal of the evidence and integration of the research findings with clinical expertise. Finally, the clinician assesses the outcome of the process and continues to improve his EBM skills.