Recent change to multiple races concept is a breaking change to a ratified convention

[scottfavre]

TL;DR - please update the article to preserve the old concept id for vocabulary versions prior to 2025 August to help out ETL authors

See 4e07e31

The ratified convention was to use concept 44814659.

Changing to the new concept 1546847 is a nontrivial change for existing sites:

• The convention now only works for OMOP instances that are on the 2025 August vocabulary version
• ETL code changes are required to use the change in the convention (it's just swapping out a concept id, but it is still a change)
• Existing data needs to be migrated
• Downstream queries need to be changed (e.g., data quality monitoring efforts, etc.)
• Any studies that were looking for multiple races with the old concept will have to update to use the new concept.

This is not to suggest that we should not keep updating Themis, the newer concept is objectively better.

Rather, it would be very useful for people relying on Themis to make decisions in their ETLs to have more information than just the latest and greatest:

• there is necessarily going to be lag between a new vocabulary release or a new Themis convention and implementation in ETLs
• It is very useful to be able to cite a Themis convention in code when we are following that convention, but if the ratified conventions can change out from under us that is less useful.

[MelaniePhilofsky]

@scottfavre

Thank you for the feedback. I agree this is a non-trivial change. I will update the wording in the convention to preserve the previous concept_id and then identify the date/vocabulary version the change was made.

[MelaniePhilofsky]

Update documentation with the following:

"The convention was updated on August 27, 2025, to reflect changes in standard concepts introduced in the August 2025 vocabulary version. Previously, the guidance was to use concept_id = 44814659 for multiple race. The current guidance is to use concept_id = 1546847."