Full definition
HL7 (Health Level Seven) refers both to the international standards-development organisation and to the family of healthcare interoperability standards it publishes. The "level seven" refers to the OSI application layer — HL7 standards govern how applications exchange healthcare data, not the underlying transport.
The HL7 family spans three generations: HL7 v2 (released 1989, still dominant in lab/imaging interfaces), CDA / CCD (Clinical Document Architecture, 2007, document-based exchange), and FHIR (Fast Healthcare Interoperability Resources, 2014+, the modern API standard). Most production healthcare environments today run all three side-by-side.
Understanding HL7 is foundational to any healthcare integration work. The choice of which HL7 standard to use depends on the integration: HL7 v2 for legacy lab/imaging interfaces, CDA for document-style exchange and government mandates, FHIR for everything new. MOVO-X integrations support all three; new work defaults to FHIR.
Where hl7 (health level seven) is used
- Lab and imaging interfaces (HL7 v2 still dominant)
- EMR-to-EMR data exchange (FHIR for new, CDA for legacy)
- Government health-data submission (CDA / CCD)
- Pharmacy benefit management (NCPDP layered with HL7)
- Public-health reporting (HL7-based standards)
Types of hl7 (health level seven)
HL7 v2
Pipe-delimited message standard from 1989. Still dominant in lab and imaging interfaces.
HL7 v3
XML-based successor to v2. Limited adoption; most implementers skipped to FHIR.
CDA (Clinical Document Architecture)
Document-based exchange standard. CCD is a CDA implementation.
CCD (Continuity of Care Document)
Patient-summary document used for transitions of care.
FHIR
Modern RESTful + JSON API standard. The default for new integrations.
Quantified benefits
- ▸Single international standards body — same vocabulary worldwide
- ▸Multi-decade backward compatibility for legacy environments
- ▸Active community + reference implementations
- ▸Global ecosystem of tooling, libraries, and certification
Frequently asked
Is HL7 a standard or an organisation?+
Both. HL7 International is the not-for-profit standards body. The HL7 family of standards is what they publish — v2, v3, CDA, FHIR, etc.
Which HL7 standard should I use?+
For any new integration: FHIR. For legacy lab/imaging: HL7 v2. For government document submission: CDA / CCD. Most integrations end up using a combination.
Is HL7 free to use?+
The standards are free to read and implement. HL7 International offers paid membership and certification programmes for organisations that want voting rights or formal certification.
Does MOVO-X support HL7?+
Yes — all three layers. FHIR R4 is the primary API; HL7 v2 is supported for legacy interfaces; CDA/CCD is supported for document exchange and government submission.
What about HL7 v3?+
Almost no production systems use HL7 v3 today. It was a 2000s effort that was overtaken by FHIR. New integrations should not target v3.