Why FHIR R4 Is the Foundation for Modern EHR Interoperability

Author: Jean Jacques Nya Ngatchou, MD | January 15, 2026

FHIR R4 is not just a standard. It is the API contract that determines whether your EHR can participate in the modern health data ecosystem.

The shift from document exchange to API-first

For decades, health IT interoperability meant HL7 v2 messages and CDA documents. FHIR R4 changes the model with RESTful APIs and standardized resources.

What FHIR R4 actually provides

FHIR defines resources—Patient, Observation, MedicationRequest, Condition—that map to clinical concepts with standard structure, search parameters, and operations.