Diagnosing jaundice expert system

Abstract DIJEST (DIagnosing Jaundice Expert SysTem) is a medical expert system which produces a differential diagnosis of a patient presenting with jaundice. DIJEST is written in Prolog, and illustrates the use of the language for clearly expressing knowledge. Specifically, the expert system contains explicit declarative knowledge of anatomy and physiology which is used by clinicians when diagnosing obstructive jaundice. The inference engine matches patient records against expected manifestations of symptoms in diseases. Novel in DIJEST is the uncertainty reasoning scheme, using contribution and absence factors, which places equal importance to symptoms present, absent and unknown in the patient's medical record. Domain specific reasoning and domain specific knowledge are clearly separated from general inference capabilities and knowledge representation schemes. DIJEST has performed well in preliminary tests, being particularly impressive for patients with multiple diseases.