Interoperability and Health Information Exchange
Health information exchange (HIE) enables clinicians, payers, and patients to access relevant health data regardless of where it was originally created. RHIA candidates must be able to identify the standards bodies and messaging formats that make this exchange possible, since interoperability questions appear frequently on the exam.
HL7 Version 2 and Version 3
Health Level Seven (HL7) Version 2 is a messaging standard used for transactions such as admission, discharge, and transfer notifications, laboratory results, and order entry. It remains widely used despite its flexible, sometimes inconsistent implementation. HL7 Version 3 introduced a more rigid, model-driven approach using the Reference Information Model but saw slower adoption due to implementation complexity.
FHIR
Fast Healthcare Interoperability Resources (FHIR) is the modern standard built on web technologies such as REST APIs and JSON, designed to simplify data exchange between systems, including mobile applications. FHIR organizes data into discrete "resources," such as Patient, Observation, and Condition, that can be requested individually rather than as a full message.
Regional and National HIE Models
HIEs can operate under a centralized model, where data is stored in a shared repository, or a federated model, where data remains at the source and is queried on demand. Health information organizations (HIOs) govern the participation agreements, consent policies, and technical infrastructure that support exchange within a region.
Direct Secure Messaging
Direct exchange uses encrypted point-to-point messaging, similar to secure email, allowing providers to send patient information directly to a known recipient without a centralized database, which is common in transitions of care such as hospital discharge summaries sent to primary care providers.
Consent and Governance Considerations
- Opt-in versus opt-out consent models affect what data can be shared
- Data use agreements define permissible uses among HIE participants
- 42 CFR Part 2 imposes additional consent requirements for substance use disorder records shared through an HIE
Exam Tip
Be ready to differentiate FHIR from HL7 Version 2 in terms of technology approach, and to identify which exchange model, centralized or federated, fits a given scenario.