DEVELOPMENT AND RETROSPECTIVE EVALUATION OF HEPAXPERT-I - A ROUTINELY-USED EXPERT-SYSTEM FOR INTERPRETIVE ANALYSIS OF HEPATITIS-A AND HEPATITIS-B SEROLOGIC FINDINGS

HEPAXPERT-I is an expert system that interprets the results of routine serologic tests for infection with hepatitis A or B virus. The tests measure antibody to the hepatitis A virus (anti-HAV), IgM antibody to the hepatitis A virus (IgM anti-HAV), hepatitis A virus (HAV) in the s tool, hepatitis B surface antigen (HBsAg) and antibody (anti-HBs), ant ibody to hepatitis B core antigen (anti-HBc and IgM anti-HBc), and hep atitis B envelope antigen (HBeAg) and antibody (anti-HBe). The knowled ge base of HEPAXPERT-I contains 13 IF-THEN rules for hepatitis A and 1 06 IF-THEN rules for hepatitis B serology. Formally, knowledge acquisi tion was done by forming a partition of each of the two sets of possib le serologic finding patterns that contain patterns of serologic test results, 64 for hepatitis A and 4096 for hepatitis B, respectively. Af ter entering an input pattern of serologic test results in HEPAXPERT-I , a rule pattern matching algorithm based on indexing is internally em ployed as efficient access method for providing the respective interpr etive text. Since 1 September 1989, HEPAXPERT-I has been routinely app lied at the Hepatitis Serology Laboratory of the 2nd Department of Gas troenterology and Hepatology at the University of Vienna Medical Schoo l (Vienna General Hospital). Beforehand, a retrospective evaluation of the expert system based on 23 368 hepatitis A and 24 071 hepatitis B serology requests was carried out.