ABSTRACT
Imagine that you are a young physician, having just completed a training program in primary care medicine. You have taken a position in a city clinic, and this is your first week on the job. Awaiting your next patient, you sit in a small examining room consisting of a chair, a stool, an examining table, and an instrument table. Remember that there are 1304 formal disease entities noted in a standard compilation (Berkowitz, 1967). Your challenge is to decide whether the incoming patient has one or more of these diseases or no medical problem whatsoever. You have 20 minutes.
