Could you please clarify what you are trying to achieve here? Why would one need to build up an additional conceptual model on top of FHIR? It is not clear here what the matter of argumentation is. What is the example of the set-up where one would use FHIR and then another conceptual model above? (By the way, the term conceptual model is not defined in this paper)

Existing Wording:

In the case of FHIR, implementer systems are already performing this transformation from their internal data models to FHIR. Introducing another conceptual model on top of that introduces another layer of mapping and transformation that must be developed, tooled, authored, implemented, and subsequently maintained over time.

Proposed Wording:

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