DEQM will reference QI-Core and QI-Core reference to identifiers CCN and NPI will use the HTA references. CQI reviewed this on 12/9/2022 and here are the findings: CQI submitted a HTA to establish a THO reference for EIN: UP-288. This tracker was withdrawn because it duplicated UP-330. In the related UTG proposal HTA-74 to UP-330, the comment from Carol stated that "HTA has reviewed and agrees that the use of URN:OID as the URI is suboptimal however, as it has been used in production, there is risk associated with altering at this point. Information about the identifier system has been gathered and documented here: https://confluence.hl7.org/pages/viewpage.action?pageId=104767034 " Here is the link to USEIN in THO: https://terminology.hl7.org/NamingSystem-USEIN.html The URI in THO is urn:oid:2.16.840.1.113883.4.4. This is consistent with the identifier used by EIN in QICore: http://hl7.org/fhir/us/qicore/2022Sep/StructureDefinition-qicore-organization.html http://hl7.org/fhir/us/qicore/2022Sep/StructureDefinition-qicore-practitioner.html Based on these findings, we do not need to make changes for the EIN identifier used in QICore.  The update to use URL as identifier for CCN is addressed in FHIR-37900 CCN https://terminology.hl7.org/NamingSystem-CCN.html The use of NPI identifier is based on USCore, which was already updated to use the URL as identifier for NPI in QICore. NPI https://terminology.hl7.org/NamingSystem-npi.html