Interoperability of Protege 2.0 beta and OilEd 3.5 in the Domain Knowledge of Osteoporosis

concepts Possible Not possible Not implemented; metaclasses are not supported Inverse relations Implemented in the tool but not useful in this ontology because slots are used in override mode. Implemented in the tool but not useful in this ontology because slots are used in override mode. Yes (Figure 4). Relation hierarchies Yes, hierarchies are graphically displayed Yes, hierarchies are graphically displayed Yes, but the hierarchy is not graphically displayed. Table 1. Comparison of the ontology-building capabilities of Protégé, Protégé+plug-in, and OilEd. Ontologies generated using the alpha DAML+OIL plug-in for Protégé can not represent properly multiple inheritance (see Figure 3). The ability to represent polyhierarchies is crucial for a biomedical ontology, so we choose not to further test this plug-in tool in our experiment. Figure 2. All concepts in our Protégé ontology have been modeled as subclasses of the Biomedical-class metaclass. Figure 3. Polyhierarchies modeled with DAML+OIL plug-in for Protégé (left pane) disappear when imported by OilEd (right pane). Figure 4. OilEd easily represents inverse properties (called slots in Protégé).