Representation of nursing terminology in the UMLS Metathesaurus: a pilot study

To see whether the National Library of Medicine's Metathesaurus (tm) includes terminology relevant to clinical nursing practice, two widely used nursing vocabularies were matched against the Meta. The two nursing vocabularies are 1) the North American Nursing Diagnosis List of Approved Diagnoses; and 2) the Omaha System, a vocabulary of problems and interventions developed by the Omaha Visiting Nurses Association. First, the terms were scanned against Meta in their "native" form, with phrases and combinations intact. This produced a relatively low percentage of exact matches (12%). Next, the terms were separated into "core concepts" and "modifiers" and the analysis was repeated. The percentage of exact matches to terms in Meta increased to 32%. However, the semantic types of the split terms often were not equivalent to the semantic types of the phrases from which the split terms were derived; also, in some cases, terms returned as exact matches had different meanings in Meta. Automatic scanning for lexical matches is a helpful first step in searching for vocabulary representation in Meta, but term-by-term search for context, semantic type and definition is essential. However, it seems clear that representation of nursing terminology in the Metathesaurus needs to be expanded.