This is the CodeSystem that contains all the codes in CDC Local Coding System (https://phinvads.cdc.gov/vads/ViewCodeSystem.action?id=2.16.840.1.114222.4.5.274) and CDC Local Coding System (https://phinvads.cdc.gov/vads/ViewCodeSystem.action?id=2.16.840.1.114222.4.5.274). E.g. what you have to deal with if you get resources containing codes in either of them