The influence of a decision support system on the differential diagnosis of medical practitioners at three levels of training.

As computer-based diagnostic consultation systems become, available, their influence and usefulness need to be evaluated. This report, based on partial data from a larger study, examines the influence of Iliad, a diagnostic consultation system, on the differential diagnosis of fourth year medical students, residents in medicine, and attendings in general internal medicine. Our results show that when faced with difficult diagnostic cases, medical students add significantly more diagnoses from Iliad's differential than do residents or attendings. However, the quality of Iliad's diagnostic advice in terms of the presence of the correct diagnosis, is no better for consultations done by students or residents compared to attendings.