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A Metadata Extraction Approach for Clinical Case Reports to Enable Advanced Understanding of Biomedical Concepts
Published on: September 20, 2018
Circular hierarchical relationships in the UMLS: etiology, diagnosis, treatment, complications and prevention
1National Library of Medicine, National Institutes of health, Bethesda, MD, USA. olivier@nlm.nih.gov
Abstract:
The Unified Medical Language System (UMLS) is a large repository of some 800,000 concepts for the biomedical domain, organized by several millions of inter-concept relationships, either inherited from the source vocabularies, or specifically generated. This paper focuses on hierarchical relationships in the UMLS Metathesaurus, and especially, on circular hierarchical relationships. Using the metaphor of a disease, we first analyze the causal mechanisms for circular hierarchical relationships. Then, we discuss methods to identify and remove these relationships. Finally, we briefly discuss the consequences of these relationships for applications based on the UMLS, and we propose some prevention measures.
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