What it the objective of ISO 13606? What are archetypes? How can I use it to enable semantic interoperability of health data? In this section you will learn the basics of ISO 13606.
ISO 13606 is a standard from the International Standardization Organization (ISO), originally designed by the European Committee for Standardization (CEN).
The overall objective of the ISO 13606 standard is to define a rigorous and stable information architecture for communicating part or all of the electronic health record (EHR) of a single subject of care (patient) between EHR systems, or between EHR systems and a centralized EHR data repository. It may also be used for EHR communication between an EHR system and clinical applications or middleware components (such as decision support components) that need to access EHR data, or as the representation of EHR data within a distributed (federated) record system.
To achieve this objective, ISO 13606 follows a Dual Model architecture. The Dual Model architecture defines a clear separation between information and knowledge. The former is structured through a Reference Model that contains the basic entities for representing any information of the EHR. The latter is based on archetypes, which are formal definitions of clinical information models, such as discharge report, glucose measurement or family history, in the form of structured and constrained combinations of the entities of a Reference Model. It provides a specific semantic meaning to a Reference Model structure. The combination of the Reference Model (to represent data instances) and the Archetype Model (to semantically describe those data) provides a powerful capability of evolution to the information systems. Clinical information models (archetypes) may change in the future, but data will always remain interoperaable.
Interoperability is the ability of diverse systems and organizations to work together seamlesly. That means exchanging information and using the information that has been exchanged. Two types of interoperability can be defined.
In the field of health information, to achieve semantic interoperability is even a more important and difficult duty. The complexity of the health domain, its frequent variation and evolution and the differences between the information technologies domain and the health domain need a deep change on the methodologies of information management. New proposals have arisen during the last decade to solve the problem of semantic interoperability of health information. Among them, the dual model approach is the most promising approach. Having not only an information reference model but also a concept model that permits to build complex domain concepts eases the transition from just data structures to semantically interoperable knowledge.
You can buy the complete standard specifications at the ISO web page, or translated (in some countries) through your national standardization organization. You can also check your University or Organization library to know if you have free access to the specifications. Additionally, you can read the ISO 13606-1 introduction section freely.
ISO 13606 is composed of five parts. Parts 1, 2 and 3 are the most relevant for a basic implementation of the standard.
A Reference Model is an Object-Oriented model that is used to represent the generic and stable properties of health record information. It includes a small set of classes that define the generic building blocks to construct EHRs. It specifies how health data should be aggregated to create more complex data structures and the context information that must accompany every piece of data in order to meet ethical and legal requirements. It does encode what it is meant, not how it is intended to be presented. ISO 13606 Reference Model contains:
The main classes that contain clinical information in ISO 13606 are represented in the following diagram.
Context information refers to all data that accompanies clninical data and helps to correctly interpret it. For exampla, data about the subject of care, the date and time of the clinical session, the time of data registry, the author, the legal authenticator, and information about any other participant in the health care process. ISO 13606 represents all that data using the following classes.
All clinical and context information represented in an ISO 13606 instance can include an identifier that references to the entity that the information refers to, or that performed a particular role during the health care activity. These entities can be a person (subject of care or health profesional), organizations, or devices. ISO 13606 includes a set of classes that represent identification and detailed data about all these entities.
The objective of the ISO 13606 demographic classes is not to support the development of a complete demographic information server, but to allow the communication of the relevant demographic data of all participants in the EHR that is being documented. Thus, in case the receiver system does not have accesss to a shared demographic server, it can at least identify the main participants in the clinical acts.
ISO 13606:2008 uses the data types specified in the technical specification TS 14796 Health informatics – Data types. The next figure shows a summary of the main data types used in the standard.
ISO 13606 is currently being revised by ISO. The new standard is expected to be ready by the end of 2017. Several changes will be introduced to make the standard more useful and simple to use. However, the new version will maintain a maximum compatibility with current ISO 13606 standard.
An archetype is a representation of a clinical information model. That means that it defines a particular configuration of the reference model, with a specific meaning. For example, an archetype can represent the information structure that corresponds to a vital signs measurement, la laboratory test, or a complete family history report.
You can see an example of an archetype in the following figure, as seen in LinkEHR Studio archetype editor:
Archetypes are built by combining and constraining the existent classes of the reference model. To build an archetype, we have to define the structure and organization of the classes, select the data types, and constrain the range of possible values that can be registered. Additionally, archetypes can be mapped to terminologies in order to provide a specific meaning for the information structure, thus making it semantically interoperable.
Another powerful chacteristic of archetypes is their reusability. Archetypes that are defined can afterwards be reused by combining them into more complex archetypes, by specializing them to fit particular scenarios of use, and by versioning them to align to new requirements.
Archetypes can be expressed using a formal language called Archetype Definition Language (ADL). This language was originally defined by openEHR and has been adopted by ISO 13606. In particular, ISO 13606:2008 supports ADL 1.4.
ADL specifications can be found in the openEHR web page: ADL 1.4 Specifications
When you build an ISO 13606 data instance, you have to bear in mind wo rules:
The following code is an example of the minimal ISO 13606 EHR Extract data instance. In this example, it does not follow any archetype specification.
<?xml version="1.0" encoding="UTF-8"?> <?xml-stylesheet type="text/xsl" href="en13606/en13606.xslt"?> <!-- EXTRACT --> <EHR_EXTRACT xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="en13606/EN13606-extract.xsd"> <ehr_system xsi:type="II"> <root xsi:type="OID"> <oid>1.2.3</oid> </root> </ehr_system> <ehr_id xsi:type="II"> <root xsi:type="OID"> <oid>1.2.3</oid> </root> </ehr_id> <subject_of_care xsi:type="II"> <extension>123456</extension> <root xsi:type="OID"> <oid>1.2.3</oid> </root> </subject_of_care> <time_created xsi:type="TS"> <time>2005-10-07T14:49:29</time> </time_created> <rm_id>UNE-EN 13606-1:2007</rm_id> <!-- Content: a COMPOSITION --> <all_compositions xsi:type="COMPOSITION"> <name xsi:type="SIMPLE_TEXT"> <originalText>Minimal document</originalText> </name> <rc_id xsi:type="II"> <root xsi:type="OID"> <oid>9876543210</oid> </root> </rc_id> <synthesised>false</synthesised> <committal xsi:type="AUDIT_INFO"> <ehr_system xsi:type="II"> <root xsi:type="OID"> <oid>1</oid> </root> </ehr_system> <time_committed xsi:type="TS"> <time>2009-03-02T21:36:12</time> </time_committed> <committer xsi:type="II"> <root xsi:type="OID"> <oid>147</oid> </root> </committer> </committal> <!-- CONTENT: an ENTRY --> <content xsi:type="ENTRY"> <name xsi:type="SIMPLE_TEXT"> <originalText>Minimal example</originalText> </name> <rc_id xsi:type="II"> <root xsi:type="OID"> <oid>123</oid> </root> </rc_id> <synthesised>false</synthesised> <uncertainty_expressed>false</uncertainty_expressed> <!-- CONTENT: an ELEMENT --> <items xsi:type="ELEMENT"> <name xsi:type="SIMPLE_TEXT"> <originalText>Hello</originalText> </name> <rc_id xsi:type="II"> <root xsi:type="OID"> <oid>123</oid> </root> </rc_id> <synthesised>false</synthesised> <!-- VALUE: a SIMPLE_TEXT --> <value xsi:type="SIMPLE_TEXT"> <originalText>world!</originalText> </value> </items> </content> </all_compositions> </EHR_EXTRACT>