Clinical Reasoning & Actuarial Prediction
Diagnosis and treatment are risky ventures. They are fraught with the possibility of error that can have serious consequences. How can error be minimized? On the one hand are the clinicians who, having elicited information that is generally both incomplete and inferential, diagnose patients and use subjective probabilities to predict outcome. On the other hand are the psychological actuaries who regard natural clinical reasoning as so flawed as to be virtually obsolete and who seek to replace it with reliable statistical formulas.
A considerable amount of research has been conducted into the fallacies and biases that can lead clinicians astray. Such research has had little effect on clinical practice for several reasons. Actuarial experiments sometimes seem artificial, irrelevant, or even rigged (against the clinician). Clinicians are prone to concede that others may make a particular mistake but that they are unlikely to do so. Indeed, clinicians often have a degree of self-confidence that enables them to survive in an uncertain world, and they are not likely to accept their defects unless they see a practical remedy. Finally, clinicians may fear that, if tampered with, their mysterious diagnostic skills will evaporate and that they will be replaced by computing machines.