Exploring the UMLS: a rough sets based theoretical framework.

The Unified Medical Language System (UMLS) [1] has a unique and leading position in the evolution of thesauri and metathesauri. Features that set it apart are: its composition from more than fifty component health care vocabularies; the sophisticated UMLS ontology linking the Metathesaurus with structures such as the Semantic Network and the SPECIALIST lexicon; and the high level of social collaboration invested in its construction and growth. It is our thesis that in order to successfully harness such a complex vocabulary for text retrieval we need sophisticated methods derived from a deeper understanding of the UMLS system. Thus we propose a theoretical framework based on the theory of rough sets, that supports the systematic and exploratory investigation of the UMLS Metathesaurus for text retrieval. Our goal is to make it more feasible for individuals such as patients and health care professionals to access relevant information at the point of need.