Healthcare organizations have accumulated many systems from billing to patient tracking. These systems need to integrate with each other to receive or retrieve new information.
HL7 or Health-Level-7 is a number of standards that regulate this very information transfer between software applications used by healthcare providers. The standards focus on the Layer 7 of application in the Open Systems Interconnection of the ISO seven-layer communications model. That is a conceptual model that covers the communication function of a system with no regard to the internal structure and technology.
Health Level Seven International is an organization that has developed HL7 standards. They are also adopted by American National Standards Institute and International Organization for Standardization.
HL7 standards define and develop formats for messaging and data exchange rules syntax and common health data definitions for clinical documentation, EHR and personal health record, quality reporting and prescription product labeling.
HL7 Primary Standards
To the Primary (the most popular standards for system integration) HL7 standards belong:
1.Version 2.x/3 Messaging Standard — an interoperability specification for health and medical transaction.
2. Clinical Document Architecture (CDA) — an XML markup standard that specifies encoding, structure and semantics of clinical documents to exchange.
3. Continuity of Care Document — an XML markup standard that specifies encoding, structure and semantics of a patient summary clinical document to exchange.
4. Structured Product Labeling — an XML-formatted standard that defines human prescription drug labeling content.
5. Clinical Context Object Workgroup — standard protocol that synchronizes disparate applications in real time at the UI level.
6. HL7 Version 2 Product Suite — allows exchange between the medical systems.
HL7 is supported by 1,600 members from all over 50 countries and its main vision is to provide everyone with a flexible access and use of the healthcare data wherever they need it.
Health Level Seven International develops new standards through the balloting system when member vote and comment during successive balloting rounds until there are no negative comments left and draft standards are agreed.
FHIR (Fast Healthcare Interoperability Resources) is a new specification from Health Level Seven International that can be used as a stand-alone data-exchange standard. FHIR delivers simplified implementation with leveraging existing logical and theoretical models.
FHIR defines all the exchangeable data as resources that share such characteristics as common set of metadata, a human-readable part and a common way of definition and representation built from data types that define common reusable patterns of elements.
The main aim of FHIR is to deliver resources that can support the majority of use cases either by themselves or when combined.