Diagnosing the diagnostic process

Experimental results obtained by examining the diagnostic performance of students and doctors in different medical schools and different cultural environments are presented. The pertinent data were obtained using tests of diagnostic skills based on real cases. The technique requires asking questions (tactics) to obtain the information needed to reach a diagnosis so that the subject becomes an active searcher of information and the final answer is not the only element used to evaluate tactics. The results show significant differences in performance according to medical experience. Experts ask fewer questions than students or less-experienced doctors but maximize the information value by asking them at the proper time in the sequence. New evaluation procedures are described to characterize quantitatively each diagnostic tactic. Experimentally based theoretical considerations are made concerning the prediction and development of diagnostic talent, the structure of diagnostic processes and its training. New approaches to the problem are briefly sketched.