title: Set theory in diagnostic reasoning.
abstract: BACKGROUND
  Regarding diagnostic reasoning, the currently taught Bayesian theory is a form of hypothetical-deduction reasoning. Using set theory, we offer syllogism reasoning instead of hypothetical-deductive reasoning and establish an online diagnostic expert system model based on this diagnostic methodology.
  
  
  METHODS
  Concepts of set theory were employed to demonstrate diagnostic reasoning. ASP, Vbscript and Microsoft Access were used to establish the expert system and data of 50 cases from Shanghai pulmonary hospital were put into the program to test its efficiency.
  
  
  CONCLUSIONS
  Diagnostic procedure is type of syllogism rather than hypothetical-deductive reasoning.
authors.affiliation: Embryological Department, The Second Military Medical University, Shanghai 200433, PR China. roseboy0227@hotmail.com
authors.forename: Rui-Bao
authors.initials: RB
authors.lastname: Tang
authors.forename: Qin-Fang
authors.initials: QF
authors.lastname: Deng
authors.forename: Hou-Qi
authors.initials: HQ
authors.lastname: Liu
mesh_terms: D016000:Cluster Analysis; D003933:Diagnosis; D003951:Diagnostic Errors; D005103:Expert Systems; D006801:Humans; D008128:Logic; D008962:Models, Theoretical