Mapping ophthalmic terms to a standardized vocabulary

The American Academy of Ophthalmology (AAO is working to expand the standardized vocabulary, Systematized Nomenclature of Medicine (SNOMED), to accommodate a definitive ophthalmic standardized vocabulary. We mapped a practice-based clinical ophthalmic vocabulary to SNOMED and to the other vocabularies in the Metathesaurus of the Unified Medical Language System (UMLS) to see what terms currently existed both in the practice-based vocabulary and in the standardized vocabularies, to identify what terms might be added to the standardized vocabularies, and to see what existing broader terms in the standardized vocabularies could be expanded. We normalized terms in our practice-based clinical ophthalmic vocabulary and compared them to normalized terms in the standardized vocabularies. We stripped off modifiers from nonmatching terms to see if the resulting stripped terms matched to broader terms in the standardized vocabularies. Twelve percent of our practice-based terms exactly matched a term in one of the standardized vocabularies (including SNOMED). About 43% of the remaining terms stripped of modifiers partially matched terms in the standardized vocabularies. Computer matching rapidly identifies what ophthalmic terms currently exist in standardized vocabularies, what broader terms in standardized vocabularies are candidates for expansion, and what terms unique to ophthalmology may need to be added to the standardized vocabularies to create a definitive ophthalmic vocabulary.