This case-sensitive code system http://hl7.org/fhir/us/davinci-deqm/CodeSystem/update-type defines the following codes:

Code	Display	Definition
incremental	Incremental	In contrast to the Snapshot Update, the FHIR Parameters resource used in a Submit Data or the Collect Data scenario contains only the new and updated DEQM and QI Core Profiles since the last transaction. If the Consumer supports incremental updates, the contents of the updated payload updates the previous payload data.
snapshot	Snapshot	In contrast to the Incremental Update, the FHIR Parameters resource used in a Submit Data or the Collect Data scenario contains all the DEQM and QI Core Profiles for each transaction. If the Consumer supports snapshot updates, the contents of the updated payload entirely replaces the previous payload