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How does it work? How does the i2b2 ontology make the patient data queryable?

This is another key topic question/concept.

The patient data in the CRC database work in tandem with the metadata in the ONT database to allow i2b2 to conduct queries for the researcher. The metadata spell out all the various healthcare concepts or terms that a researcher may wish to query for in the user interface, and the patient data must be coded in such a way that they reflect the codes defined in the metadata.

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