Evidence-based medicine - or "EBM" which slips off the tongue more readily - seeks to offer proof that what we offer patients whenever we treat them is known to be effective. Fifty to 100 years ago, health care was delivered patchily, much less of it was effective, and was based on an image of a kindly and well intentioned doctor treating his sick patient, who was glad of whatever help could be offered. Now, medicine is effective and whether you...