Decision rules, types of error, and their consequences in medical diagnosis

“It can be of no importance to me of what religion my physician or my lawyer is; this consideration has nothing in common with the offices of friendship which they owe me.”—Montaigne Not so, says the author of this article: the moral code of a physician or a lawyer has a great deal to do with the professional services which he supplies to his clients. When a judge, a jury, or a doctor must decide a case or make a diagnosis on the basis of insufficient or conflicting evidence, the final decision is based to a considerable extent on moral and ethical standards. Some kinds of wrong decisions are felt to be less harmful than others, and when risk of error is present, the less harmful decision will usually be made. This article discusses a particular decision rule of the medical profession, and some possible harmful consequences of its application.