Figure 2

SNOMED CT redesign according to the SDP modeling approach. Peculiar SNOMED CT concepts are encased in dotted boxes to be better identifiable in the new model. The concepts of the structure – disposition – process triple and the resulting subsumptions to them are emphasized by bold lines. Left: Current SNOMED CT hierarchy (simplified). Diseases do not distinguish between pathological processes and pathological disorders. Morphological abnormalities are in a separate hierarchy, as well as events. Right: Redesigned upper level. Clinically relevant structural abnormalities, dispositions and processes are subsumed by a new "Condition" node. The former disease classes can be disambiguated by introducing a new is-a link to Process and Disposition, respectively (example D2a and D2b). Morphological abnormalities are also subsumed by Disease/Disorder. Events are processes.