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README.md

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 # i2o-transform
-PCORnet Ontology to OMOP - under construction!
+### PCORnet Ontology to OMOP - under construction!
+
+An experimental fork of the i2b2-to-PCORNET transform that targets OMOP, for the [Precision Medicine Initiative](https://www.nih.gov/research-training/allofus-research-program).
+
+[See OMOP documentation and DDL here.](https://github.com/OHDSI/CommonDataModel)