HL7 FHIR
The healthcare interoperability standard defining how clinical data is structured and exchanged over modern web APIs.
FHIR defines clinical concepts as resources — Patient, Observation, Condition, MedicationRequest — exchanged as JSON or XML over REST. That made healthcare integration approachable to developers who had never seen HL7 v2's pipe-delimited messages, and it is why almost all new healthcare integration work targets it.
The standard being modern does not make integration simple. FHIR permits extensive profiling, so two compliant systems can represent the same clinical fact differently; vendors implement different subsets; and access is gated by scopes and consent frameworks such as SMART on FHIR. In practice, building against FHIR means building against a specific vendor's interpretation of it and discovering the gaps during integration rather than from the specification.
In practice
A product integrated with two EHR vendors using the same FHIR resources. One returned medication data as MedicationRequest, the other as MedicationStatement with different fields populated. Both were compliant. The reconciliation logic ended up larger than the feature it supported.
Where teams get it wrong
- Assuming FHIR compliance means two systems represent data the same way.
- Building against the specification instead of against the target vendor's implementation.
- Underestimating scopes, consent and the SMART on FHIR authorisation layer.
- Treating optional fields as reliably present.
- Designing interfaces that assume complete records, which real data rarely is.
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Related terms
All terms- Electronic Health Record (EHR)The digital record of a patient's health information across providers — and the system clinicians spend most of their screen time inside.
- Audit LogAn immutable record of who did what and when — required by enterprise buyers and compliance frameworks, and usually built as an afterthought.
- Data TableA grid of rows and columns for scanning, comparing and acting on records — the screen most B2B users spend their day inside.
- Accessibility AuditA structured evaluation of a product against WCAG, producing a list of failures with severity, location and a route to fixing each one.