Medical differential diagnostic system (DDS) using fuzzy inferencing methods

In the paper the problem of differential diagnosis (DDP) in the area of medicine is addressed. These DDP´s can be represented in the standard form, an extension of clausal form, as disjunction of conclusions as: D₁;D₂;D₃;. . .;D_m ←S₁,S₂,S₃,. . .,S_n. Where S_i, i=1,n are the symptoms and D_i , i=1,m are the diagnoses. In order to handle this problem symbolically through the techniques of expert systems, the degree of severeness (or the multivalued nature) of the symptoms that leads to different diagnoses is difficult to represent. Fuzzy sets are used to represent the symptoms and the diagnoses. Fuzzy relations are used to store the knowledge of historical cases. The system provides methods of incrementing the knowledge in a fuzzy relational base