The purpose of the LOINC Change Snapshot File is to provide a structured record of the key changes to LOINC content that occurred in this release. The contents of this file are currently limited to changes in the Status of LOINC Terms and LOINC Parts since the last release. We intentionally do not include terms first added to LOINC in this release, since that information is already available in the LOINC Table via the VersionFirstReleased field.

In these files, we purposefully used the Property field to carry the identification of the attribute of the LOINC Term or Part that changed. This use of Property is the same meaning as in our FHIR CodeSystem representation, and not the same as the (Kind of) Property of the LOINC Fully Specified Name.

We intend to expand the set of changes represented in this artifact over time, both in terms of number of attributes and the set of release artifacts. Within our internal LOINC management system, we are now tracking "change reasons" at the more detailed field level (rather only than at the level of the whole Term) and therefore in this artifact will be able to reflect this more precise, field-level information. The Change Snapshot file is a work in progress and we are eager to hear user feedback about the approach.