Medical practice guidelines: lessons from the United States.

Clinical guidelines, or protocols, have been devised by many different groups, often with differing aims. Some aim to reduce variations in care by using guidelines, while others seek to improve outcomes. Guidelines have long been used in the United States to try to control the behaviour of the medical profession--and the cost of health care. The "effectiveness initiative," run by the Agency for Health Care Policy and Research spawned much activity among other groups, including the American Medical Association and the American College of Physicians. The experience of the Americans in analysing data to gauge effectiveness and then in disseminating good practice may help British moves in this direction. In particular, it is often hard to get guidelines adopted in practice; doctors have to be exposed to the same message in different forms. Also guidelines must not be unrealistic: those devised by senior doctors away from the realities of day to day practice are likely to fail.