eHealth standards

In order to process EHR data safely, semantic interoperability is required, meaning that computational services are enabled to reliably interpret clinical data that has been integrated from diverse sources. So far various initiatives have contributed towards establishing a semantic framework for health records as described below.

Health Level Seven (HL7)

Founded in 1987,  Health Level Seven (HL7) International is a not-for-profit, ANSI-accredited standards development organization dedicated to providing a comprehensive framework and related standards for the exchange, integration, sharing, and retrieval of electronic health information that supports clinical practice and the management, delivery and evaluation of health services.

HL7 Clinical Document Architecture (CDA) HL7 CDA is the Clinical Document Architecture, an ANSI-certified standard from Health Level Seven (HL7.org). Release 1.0 was published in November, 2000 and Release 2.0 was published with the HL7 2005 Normative Edition. Currently, HL7 is working on CDA release 3.0.  HL7 CDA is specifies the syntax and supplies a framework for specifying the full semantics of a clinical document.

Integrating the Healthcare Enterprise (IHE)

Integrating the Healthcare Enterprise (IHE) promotes the coordinated use of standards such as DICOM and HL7 to address specific clinical needs in support of optimal patient care. Using existing standards it develops a domain specific profile: IHE profiles address critical interoperability issues related to information access for carers & patients, clinical workflow, security, administration, information infrastructure.

IHE Patient Care Coordination Technical Framework IHE Patient Care Coordination (PCC) Technical Framework domain was established in 2005 to deal with integration issues that cross providers, patient problems or time. It deals with general clinical care aspects such as document exchange, order processing, and coordination with other specialty domains. PCC also addresses workflows that are common to multiple specialty areas and the integration needs of specialty areas that do not have a separate domain within IHE.
IHE Profile XPHR – Exchange of Patient Health Records Being a part in IHE PCC, specific for PHR and EHRs data exchange, the IHE describes the XPHR Profile, the profile for the Exchange of Patient Health Records. The IHE Exchange of Patient Health Record Content Profile (XPHR) specifies HL7 document exchange standards and processes described as: PHR update and PHP Extract, two processes to exchange patient information between an EHR and PHR.
IHE Care Management Profile The Care Management Profile (CM) supports the exchange of information between HIT systems and applications used to manage care for specific conditions. More and more, special purpose care management systems are used to support wellness programs, public health monitoring, tracking of immunizations and infectious diseases, and to manage the care of patients with chronic diseases such as diabetes and cancer.

ISO 13606

The international standard ISO 13606 – Health Informatics — Electronic Health Record Communication was originally developed by the European Committee for Standardization. In 2008 it was adopted as an international standard by the International Organization for Standardization. It aims to enable interoperable exchange of health data between electronic health record (EHR) systems. The specified information architecture makes use of a reference model in combination with archetypes. It takes a so called „dual model approach“, that separates the medical knowledge from the technical concerns.

Terminology Standards

LOINC Logical Observation Identifiers Names and Codes (LOINC) is a universal standard for identifying laboratory observations and clinical results. Since its inception, it has expanded to include not just medical and laboratory code names, but also nursing diagnosis, nursing interventions, outcomes classification, and patient care data set.
SNOMED CT The Systematized Nomenclature of Medicine Clinical Terms (SNOMED CT), developed and promoted by the International Health Terminology Standards Development Organisation (IHTSDO), is considered to be the most comprehensive, multilingual healthcare terminology in the world. It contains a systematically organized computer processable collection of medical terminology covering most areas of clinical information such as diseases, findings, procedures, microorganisms, and pharmaceuticals. It allows a consistent way to index, store, retrieve, and aggregate clinical data across specialties and sites of care. SNOMED CT is a compositional concept system based on Description Logic, which means that concepts can be specialised by combinations with other concepts.
ICD-10 The International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10) is a coding system of diseases and signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or diseases, as classified by the World Health Organization (WHO). It is used to classify diseases and other health problems recorded on many types of health and vital records including death certificates and health records.
UMLS The Unified Medical Language System (UMLS) is a controlled compendium of many medical vocabularies, also providing a mapping structure between them. It is composed of the following three main knowledge components:

  • The Metathesaurus forms the base of the UMLS and it comprises over one million biomedical concepts and five million concept names, all of which are from over a hundred controlled vocabularies and classification systems such as ICD-9, SNOMED and LOINC. The purpose of the Metathesaurus is to provide a basis of context and inter-context relationships between these various coding systems and vocabularies to provide a common basis of information exchange between the varieties of clinical systems.
  • The Semantic Network is designed to categorize concepts in the UMLS Metathesaurus and provide relationships among the concepts. It has 135 semantic types and 54 semantic relationships.

The SPECIALIST Lexicon contains syntactic (how words are put together to create meaning), morphological (form and structure) and orthographic (spelling) information for biomedical terms.