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How should I choose which ontology to use?

This is the most important question on this pagea key question/concept.

The ontology you choose depends on your institution's goals and patient data. If your goal is simply to understand and show how i2b2 works, then the i2b2 demo ontology is sufficient. If your goal is to set up i2b2 for research use, one of the ACT ontologies will be far more useful. The ACT ontologies are more modern, more robust, and will satisfy the needs of more researchers.

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