Based on research by Leo Petersen-Khmelnitski, Cecilia Price and Joe-Max Wakim
When the same software may work at two different computers, we consider these computers to be compatible. Many think first of compatibility when interoperability is mentioned. However, interoperability means much more. Interoperability is a capacity of an IT system to work with another IT system with no restrictions.
Layers of Interoperability
Four layers of interoperability in IT have been defined so far:
- legal (laws adopted to allow these IT systems to cooperate each other)
- organisational (organisations cooperate to make it happen)
- technical (common standards, data exchange protocols defined and software deployed to ensure this mutual work)
- semantic (both systems use the same words/phrases and syntax to describe an object or a data request)
In the context of interoperability, standards – technical and semantic – are important. Not only do they provide a common language, they also provide a common set of expectations of users of these IT systems. Thus, interoperability standards are neither software nor hardware, but rather guidelines that developers can or must use to develop healthcare information systems that will inherently be compatible with other systems adhering to these same standards.
Interoperability standards in healthcare
In healthcare, interoperability standards are developed by a wide variety of healthcare organisations including regulators, vendors, consultants and healthcare providers, most often by their technical committees. There are several international standards development organisations that have developed standards that have achieved widespread adoption around the world:
- International Standards Organisation (ISO)’s technical committee TC215 (health informatics). 157 countries are ISO members.
- European Committee for Standardisation (CEN)’s TC251 (EHR, messaging, eHealth). Most European countries are members.
- Health Level Seven (HL7) accredited by the American National Standards Institute (inter alia, clinical data)
- OpenEHR focuses on semantic interoperability in EHRs
- Integrating the Healthcare Enterprise (IHE) is not an SDO, but is engaged in building models to use other standards.
In the early days, interoperability standards were developed at national levels. However, nowadays purely national standards are fairly rare. Here is a non-exhaustive list with examples of international standards that have been adopted to promote native global interoperability in healthcare:
- The HL7 v2.x and v3.x suite of standards is one of the most widely used standards for communicating clinical data among clinical information systems in hospitals and general practice in the world. Fast Healthcare Interoperability Resources (FHIR) that belongs to this group is a standard that describes data formats and elements (“resources”) and an application programming interface to exchange electronic health records. FHIR (pronounced as ‘fire’) is standard that is followed by a significant number of healthcare providers worldwide. Another interesting example is IPS. Its International Patient Summary document is an electronic health record extract containing essential healthcare information about a subject of care
- Electronic Data Interchange for Administration, Commerce and Transport (EDIFACT) is a messaging standard maintained by the United Nations Centre for Trade Facilitation and Electronic Business
- Systematised Nomenclature of Medicine Clinical Terms (SNOMED CT) is the largest clinical terminology currently available internationally. SNOMED CT was maintained by the International Health Terminology Standards Development Organisation (IHTSDO) based in Denmark. Since 2015, Snomed CT is owned by Snomed International with HQ in the UK.
- International Classification of Diseases (ICD) developed by WHO is the standard tool for epidemiology, health management and clinical purposes
- Digital Imaging and Communications in Medicine Committee (DICOM) is a standard for handling, storing, printing, and transmitting information in medical imaging
- Logical Observation Identifiers Names and Codes (LOINC) a widely used terminology system, developed to provide a definitive standard for identifying clinical information in electronic laboratory reports
How to Achieve Global Standards
Though any single global set of standards is not likely to be introduced as mandatory, there are exciting developments in the direction of a global standard in both FHIR, International Patient Summary, and others. In order to achieve true interoperability it is important to ensure that various sets of interoperability standards are interoperable with each other. This can be achieved through harmonisation of standards, an area in which nations have accrued much experience.
We may assume that the application of this experience in interoperability standards to harmonise international and national interoperability standards in healthcare will be the next strategic direction to major stakeholders in the global healthcare system.