The application may allow a user to refine a Concept by selecting a subtype of one of its defining characteristics. A defining characteristic is a relationship to a target Concept that is always necessarily true from any instance of the source Concept.
Refinement options may be entered by selecting from hierarchical lists showing subtype values. Simple lists or option buttons could support selection from limited sets of possible refinements. Wider ranges of possible refinement could be facilitated by text searches constrained to subtypes of one or more of the refineable characteristics.
One of the defining characteristics the Concept | total replacement of hip | is | using | = | hip prosthesis. | The Concept | total replacement of hip | could be refined by allowing the user to specify one of the subtypes of "hip prosthesis."
Figure 6.4.1-1: Entry of refined defining characteristics