Why bother trying to discover how clinicians make decisions? Would it really make any difference to the quality of care if we knew more about their decision making processes? Is there any basis for the conventional assumption that it would make a significant difference, and in the right direction?

Probably not. During the three decades since the pioneering work of Elstein et al,¹ numerous studies of the decision making behaviour of clinicians—and, indeed, professionals in many fields—have yielded only one relevant finding. Insofar as we can make inferences about how they decide what to do by observing their behaviour or interrogating them, their decisions and decision processes vary enormously. Even when researchers are able to come up with generalisations about the diagnostic or therapeutic processes of practitioners, these are often weakly supported and/or highly restricted in their coverage. Above all, they are analytically vague. This is not surprising because, even though some explicitly analytical reasoning is usually reported by practitioners, the expertise applied in professional decision making appears to be substantially intuitive, involving significant amounts of either intuitive pattern recognition or intuitive regression across “multiple fallible indicators”.² The disappointing results from the vast amounts of money and effort put into developing “expert systems” of …