Once the API finishes analysing a recording, it doesn’t just produce a report for a person to read — it also produces a structured data file that a hospital’s electronic health record (EHR) system can read automatically. That file is formatted to the HL7 FHIR R4 standard.
What FHIR is, in plain terms
FHIR (Fast Healthcare Interoperability Resources) is the internationally recognised standard for exchanging health data electronically. It’s the format increasingly required by national health IT frameworks, including NHS England’s API standards and the EU’s European Health Data Space regulation. Producing FHIR output means an ERG result generated by this API can be sent straight into a hospital’s existing systems — a patient chart, a specialist referral queue, a clinical audit database — without anyone re-typing the numbers by hand.
What’s actually inside the FHIR output
A completed study is packaged as a FHIR “Bundle” containing:
- One Observation resource for each recording protocol and eye tested, carrying the measured values and using standard LOINC medical codes where they exist
- One DiagnosticReport resource summarising the Green/Amber/Red result and the plain-language Layer 2 clinical narrative
- One AuditEvent resource carrying the full Layer 4 technical audit trail
Together, these three resource types mean the traffic-light result, the clinical explanation, and the underlying audit record all travel together as a single, standard, machine-readable package — not just the headline result on its own.
Why this matters for a screening tool
Retinal screening — particularly in diabetic retinopathy monitoring — often depends on results being visible across different systems and different clinical teams, sometimes across different sites entirely. Producing HL7 FHIR R4 output means the API’s results can slot directly into that existing health IT infrastructure, supporting the same kind of referral and audit pathways researchers and regulators already expect from a clinical decision-support tool, rather than requiring a bespoke integration for every deployment site.