Health Data Standards: From FHIR to ICDs

Health data flows across clinics, labs, and insurers every day. To keep it useful, we rely on standards that define how data is created, stored, and shared. Two big families stand out: FHIR for exchanging clinical data, and ICDs for classifying diagnoses and procedures.

FHIR, short for Fast Healthcare Interoperability Resources, is an HL7 framework designed for modern apps. It uses resources—like Patient, Observation, and Condition—that can be sent over the web using REST, with data in JSON or XML. This makes it easier for health apps to read, write, and combine records without bulky file transfers. When teams plan a new system, they often start by choosing the FHIR resources they will need and by setting up a reliable terminology service to interpret codes.

ICD codes describe diseases and events for billing, reporting, and public health. ICD-10-CM is common in the United States today, while ICD-11 is gaining traction worldwide for statistics and research. These codes turn medical stories into numbers that insurers, hospitals, and researchers can compare across time and places.

Putting FHIR and ICDs together is powerful but not automatic. A patient record may include a Condition resource with a code. That code could be an ICD-10-CM code for billing, a SNOMED CT code for clinical detail, or both. Many health systems rely on mappings or terminology services to connect different coding systems. Keeping mappings up to date is essential, as releases and revisions happen regularly.

Practical tips for teams: use a dedicated terminology service that can map between SNOMED, ICD, and LOINC; keep code sets current with regular releases; prefer clinical codes like SNOMED for care notes and use ICD when reports or claims require it; document your chosen versions and data sources; implement FHIR value sets to control which codes can appear in a resource.

The impact is real. When partners share aligned codes and formats, care teams see a more complete patient picture, researchers access cleaner data, and payers process claims more smoothly. The journey from FHIR APIs to robust ICD reporting supports safer, clearer health information exchange for everyone.

Key Takeaways

  • FHIR enables modern, API-based data exchange across systems.
  • ICD codes support consistent billing and public health reporting.
  • Use terminology services and mappings to connect FHIR data with ICD and SNOMED.