[DRUG_ERA](https://github.com/OHDSI/CommonDataModel/wiki/DRUG_ERA)  
[DOSE_ERA](https://github.com/OHDSI/CommonDataModel/wiki/DOSE_ERA)  
[CONDITION_ERA](https://github.com/OHDSI/CommonDataModel/wiki/CONDITION_ERA)  

These tables contain information about the clinical events of a patient that are not obtained directly from the raw source data, but from other tables of the CDM. 
Below provides an entity-relationship diagram highlighting the tables within the Standardized Derived Elements portion of the OMOP Common Data Model:

![](http://www.ohdsi.org/web/wiki/lib/exe/fetch.php?media=documentation:cdm:standardized_derived_elements_3.png)\