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A grammar-based classification of negations in clinical radiology reports
1Stanford Medical Informatics and the Stanford Center for Clinical Informatics, Stanford University Schools of Medicine, CA, USA.
Abstract:
We describe the development of a classification scheme of negations based on syntactical categories of negative words, and patterns of negation. Each category contains a negative word or phrase and a pattern to locate negated terms. The classification was derived through literature study and manual inspection of 500 radiology reports of six common imaging modalities.
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