I am not quite understanding the solution. Our typical design is that there is a standard vocabulary that you map to, and there are classification hierarchies that help you use that vocabulary.
In this case, the source vocabularies have concepts that are lower granularity than LOINC and don’t exist in LOINC. Mapping them to the hierarchy is not what we normally do, I think, and it would mean the hierarchy would also be a standard vocabulary.
And I thought LOINC was supposed to create lower granularity groups, but not sure where that is.
So is the solution to make LOINC and SNOMED both standard, where SNOMED is also the hierarchy, or add brand new OHDSI concepts to cover lower granularity, or to create OHDSI concepts for parts of LOINC terms (e.g., concept measured) and make them also standard?