Categorizing the Relationships between Structurally Congruent Concepts from Pairs of Terminologies for Semantic Harmonization

In this paper, we are using "structurally congruent concepts" in pairs of terminologies to suggest methods for harmonizing the terminologies. Two concepts are structurally congruent if they are children of the same more general concept and parents of the same more specific concept in two different terminologies. We show that structurally congruent concepts can be interpreted in six useful ways, e.g., as new synonyms. All structurally congruent concepts were found for six terminologies from the UMLS, each paired with SNOMED CT. In total, 1384 concept pairs were discovered. Concepts from a sample of 241 pairs were analyzed by a human expert. It was found that 59.3% indicated alternative classifications of the same general concept. This discovery allows an ontology designer to make existing, implicit knowledge explicit. Another 14.5% were newly discovered synonyms, 23.6% suggested the import of a concept into a terminology and 2.5% indicated errors in a terminology.