Organization of a knowledge base by Q-analysis

Abstract

Q-analysis is used in organizing a histopathological knowledge base which is a component of the diagnostic expert system at the University of Arizona. This expert system has three subsystems or modules: the first module guides the dynamic reconfiguration of the computer system; the second module guides scene decomposition and the extraction of diagnostic information; the third module uses a rule-based system to obtain a diagnostic assessment. A specific example of the usefulness of Q-analysis is given in the context of the third module; the data represent expert opinion concerning diagnosis of colonic cancer and are summarized in a matrix representing four diagnostic categories and nineteen diagnostic clues. The example shows that Q-analysis may be helpful to diagnosticians in defining and explaining the process they use in arriving at a diagnosis and in using this information as a basis for structuring the knowledge base.