AI/Consult: a prototype directed history system based upon the AI/Rheum knowledge base.

An expert system is designed which uses the AI/Rheum knowledge base as the basis for a directed workup system for rheumatological disorders. A Turbo Pascal prototype is demonstrated which, unlike AI/Rheum, permits entry by the clinician of a patient's chief complaint(s) and subsequently develops a dynamic differential diagnosis for this limited set of findings. The system restricts its line of questioning to those pertinent in order to rule in or rule out items on this dynamic differential diagnosis, and, unlike AI/Rheum, it provides immediate notification to the user when a critical mass of information has been entered in order to meet a diagnosis at one of the AI/Rheum criteria table's three levels of diagnosis (possible, probable, definite). Thus the system allows for a more rapid, focused decision making approach than does AI/Consult, while it follows the trend established by QMR in that it abandons the Greek Oracle problem solving approach and instead adopts a physician-assisted hypothesis investigation approach. The system is currently a prototype, without AI/Rheum's page oriented and mouse driven interface, and thus the total user interaction time may be longer than with AI/Rheum even though fewer user interactions (responses) are required. Plans for future development include optimization of the knowledge base to allow for more efficient, problem oriented questioning and modification of the knowledge base compiler in order to dynamically rule out diseases through the addition of three new levels of diagnosis in the knowledge base criteria tables.