Abstract

The basis for ‘sound’ medical opinion has moved from clinical opinion to evidence based research. This article will comment on the basis on which evidence in clinical medicine is collected and, indeed, what actually constitutes evidence. It is suggested that the definition of guidelines arising from evidence-based medicine may lead to false conclusion and, as noted by Sir Douglas Black, whilst ‘guidelines can of course be helpful in clear-cut situations; [but] these are the minority in actual practice’.