Medical facts to support inferencing in natural language processing

We report on the use of medical facts to support the enhancement of natural language processing of biomedical text. Inferencing in semantic interpretation depends on a fact repository as well as an ontology. We used statistical methods to construct a repository of drug-disorder co-occurrences from a large collection of clinical notes, and this resource is used to validate inferences automatically drawn during semantic interpretation of Medline citations about pharmacologic interventions for disease. We evaluated the results against a published reference standard for treatment of diseases.