Health Level 7

Last updated

Health Level Seven, abbreviated to HL7, is a range of global standards for the transfer of clinical and administrative health data between applications with the aim to improve patient outcomes and health system performance. The HL7 standards focus on the application layer, which is "layer 7" in the Open Systems Interconnection model. The standards are produced by Health Level Seven International, an international standards organization, and are adopted by other standards issuing bodies such as American National Standards Institute and International Organization for Standardization. There are a range of primary standards that are commonly used across the industry, as well as secondary standards which are less frequently adopted.

Contents

Purpose

Health organizations typically have many different computer systems used to process different patient administration or clinical tasks, such as billing, medication management, patient tracking, and documentation. All of these systems should communicate, or "interface", with each other when they receive new information or when they wish to retrieve information. HL7 International specifies a number of flexible standards, guidelines, and methodologies by which these healthcare systems can communicate with each other. The standards allow for easier 'interoperability' of healthcare data as it is shared and processed uniformly and consistently by the different systems. This allows clinical and non-clinical data to be shared more easily, theoretically improving patient care and health system performance. [1]

Primary standards

HL7 International considers the following standards to be its primary standards – those standards that are most commonly used and implemented: [2]

Other HL7 standards/methodologies include: [3]

HL7 Version 2

The HL7 version 2 standard (also known as Pipehat) has the aim to support hospital workflows. It was originally created in 1989. [4]

HL7 version 2 defines a series of electronic messages to support administrative, logistical, financial as well as clinical processes. Since 1987 the standard has been updated regularly, resulting in more than ten iterations. The v2.x standards are backward compatible, meaning a message based on version 2.3 will be understood by an application that supports version 2.6.

HL7 v2.x messages use a non-XML encoding syntax based on segments (lines) and one-character delimiters. [5] Segments have composites (fields) separated by the composite delimiter. A composite can have sub-composites (components) separated by the sub-composite delimiter, and sub-composites can have sub-sub-composites (subcomponents) separated by the sub-sub-composite delimiter. The default delimiters are carriage return for the segment separator, vertical bar or pipe (|) for the field separator, caret (^) for the component separator, ampersand (&) for the subcomponent separator, and number sign (#) for the default truncation separator. The tilde (~) is the default repetition separator. Each segment starts with a 3-character string that identifies the segment type. Each segment of the message contains one specific category of information. Every message has MSH as its first segment, which includes a field that identifies the message type. The message type determines the expected segment types in the message. [6] The segment types used in a particular message type are specified by the segment grammar notation used in the HL7 standards.

The following is an example of an admission message. MSH is the header segment, PID the Patient Identity, PV1 is the Patient Visit information, etc. The 5th field in the PID segment is the patient's name, in the order, family name, given name, second name (or their initials), suffix, etc. Depending on the HL7 V2.x standard version, more fields are available in the segment for additional patient information.

MSH|^~\&|MegaReg|XYZHospC|SuperOE|XYZImgCtr|20060529090131-0500||ADT^A01^ADT_A01|01052901|P|2.5 EVN||200605290901|||| PID|||56782445^^^UAReg^PI||KLEINSAMPLE^BARRY^Q^JR||19620910|M||2028-9^^HL70005^RA99113^^XYZ|260 GOODWIN CREST DRIVE^^BIRMINGHAM^AL^35209^^M~NICKELL’S PICKLES^10000 W 100TH AVE^BIRMINGHAM^AL^35200^^O|||||||0105I30001^^^99DEF^AN PV1||I|W^389^1^UABH^^^^3||||12345^MORGAN^REX^J^^^MD^0010^UAMC^L||67890^GRAINGER^LUCY^X^^^MD^0010^UAMC^L|MED|||||A0||13579^POTTER^SHERMAN^T^^^MD^0010^UAMC^L|||||||||||||||||||||||||||200605290900 OBX|1|NM|^Body Height||1.80|m^Meter^ISO+|||||F OBX|2|NM|^Body Weight||79|kg^Kilogram^ISO+|||||F AL1|1||^ASPIRIN DG1|1||786.50^CHEST PAIN, UNSPECIFIED^I9|||A

HL7 v2.x has allowed for the interoperability between the plethora of digital health systems, from Patient Administration Systems, to Electronic Health Records, and specialised Laboratory and Radiology Information Systems. Currently, the HL7 v2.x messaging standard is supported by every major health informatics vendor in the United States. [7]

HL7 Version 3

The HL7 version 3 standard has the aim to support all healthcare workflows. [8] Development of version 3 started around 1995, resulting in an initial standard publication in 2005. The v3 standard, as opposed to version 2, is based on a formal methodology (the HDF) and object-oriented principles.

RIM - ISO/HL7 21731

The Reference Information Model [9] (RIM) is the cornerstone of the HL7 Version 3 development process and an essential part of the HL7 V3 development methodology. RIM expresses the data content needed in a specific clinical or administrative context and provides an explicit representation of the semantic and lexical connections that exist between the information carried in the fields of HL7 messages. [10]

HL7 Development Framework - ISO/HL7 27931

The HL7 Version 3 Development Framework (HDF) is a continuously evolving process that seeks to develop specifications that facilitate interoperability between healthcare systems. The HL7 RIM, vocabulary specifications, and model-driven process of analysis and design combine to make HL7 Version 3 one methodology for the development of consensus-based standards for healthcare information systems interoperability. The HDF is the most current edition of the HL7 V3 development methodology.

The HDF not only documents messaging, but also the processes, tools, actors, rules, and artifacts relevant to the development of all HL7 standard specifications. Eventually, the HDF will encompass all of the HL7 standard specifications, including any new standards resulting from the analysis of electronic health record architectures and requirements.

HL7 specifications draw upon codes and vocabularies from a variety of sources. The V3 vocabulary work ensures that the systems implementing HL7 specifications have an unambiguous understanding of the code sources and code value domains they are using.

V3 Messaging

The HL7 version 3 messaging standard defines a series of Secure Text messages (called interactions) to support all healthcare workflows.

HL7 v3 messages are based on an XML encoding syntax, as shown in this example: [11] : 2.2.1 

<POLB_IN224200ITSVersion="XML_1.0"xmlns="urn:hl7-org:v3"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><idroot="2.16.840.1.113883.19.1122.7"extension="CNTRL-3456"/><creationTimevalue="200202150930-0400"/><!-- The version of the datatypes/RIM/vocabulary used is that of May 2006 --><versionCodecode="2006-05"/><!-- interaction id= Observation Event Complete, w/o Receiver Responsibilities --><interactionIdroot="2.16.840.1.113883.1.6"extension="POLB_IN224200"/><processingCodecode="P"/><processingModeCodenullFlavor="OTH"/><acceptAckCodecode="ER"/><receivertypeCode="RCV"><deviceclassCode="DEV"determinerCode="INSTANCE"><idextension="GHH LAB"root="2.16.840.1.113883.19.1122.1"/><asLocatedEntityclassCode="LOCE"><locationclassCode="PLC"determinerCode="INSTANCE"><idroot="2.16.840.1.113883.19.1122.2"extension="ELAB-3"/></location></asLocatedEntity></device></receiver><sendertypeCode="SND"><deviceclassCode="DEV"determinerCode="INSTANCE"><idroot="2.16.840.1.113883.19.1122.1"extension="GHH OE"/><asLocatedEntityclassCode="LOCE"><locationclassCode="PLC"determinerCode="INSTANCE"><idroot="2.16.840.1.113883.19.1122.2"extension="BLDG24"/></location></asLocatedEntity></device></sender><!-- Trigger Event Control Act & Domain Content --></POLB_IN224200>

Clinical Document Architecture

The HL7 Clinical Document Architecture (CDA) is an XML-based markup standard intended to specify the encoding, structure and semantics of clinical documents for exchange. [12] The standard was jointly published with ISO as ISO/HL7 27932.

Continuity of Care Document

The Continuity of Care Document framework is a US-specific standard for the exchange of medical summaries, based on the Clinical Document Architecture standard.

Structured Product Labeling

Structured Product Labeling describes the published information that accompanies a medicine, based on HL7 Version 3.

Clinical Context Object Workgroup

CCOW, or "Clinical Context Object Workgroup," is a standard protocol designed to enable disparate applications to share user context and patient context in real-time, and at the user-interface level. CCOW implementations typically require a CCOW vault system to manage user security between applications.

Other standards and methods

Fast Healthcare Interoperability Resources (FHIR)

Fast Healthcare Interoperability Resources is a modern interoperability specification from HL7 International designed to be easier to implement, more open, and more extensible than HL7 versions 2.x or 3.x. It leverages a modern web-based suite of API technology, including a HTTP-based RESTful protocol, HTML and Cascading Style Sheets for user interface integration, a choice of JSON or XML for data representation, OAuth for authorization and ATOM for query results. [13] The main purpose of the FHIR standard is to ensure interoperability between different computer systems. It defines the data format and protocol for exchanging medical information, regardless of how it is stored in these systems. [14]

Services Aware Interoperability Framework

The HL7 Services-Aware Enterprise Architecture Framework (SAIF) provides consistency between all HL7 artifacts, and enables a standardized approach to Enterprise Architecture (EA) development and implementation, and a way to measure the consistency.

SAIF is a way of thinking about producing specifications that explicitly describe the governance, conformance, compliance, and behavioral semantics that are needed to achieve computable semantic working interoperability. The intended information transmission technology might use a messaging, document exchange, or service approach.

SAIF is the framework that is required to rationalize interoperability of other standards. SAIF is an architecture for achieving interoperability, but it is not a whole-solution design for enterprise architecture management.

Arden syntax

The Arden syntax is a language for encoding medical knowledge. HL7 International adopted and oversees the standard beginning with Arden syntax 2.0. These Medical Logic Modules (MLMs) are used in the clinical setting as they can contain sufficient knowledge to make single medical decisions.[ citation needed ] They can produce alerts, diagnoses, and interpretations along with quality assurance function and administrative support. An MLM must run on a computer that meets the minimum system requirements and has the correct program installed. Then, the MLM can give advice for when and where it is needed.

Clinical Quality Language

Clinical Quality Language (CQL) is a ANSI certified [15] clinically focused high-level expression language standard curated by Health Level 7. [16] It is designated for clinical knowledge sharing in the domains of electronic clinical quality measurement and clinical decision support. [17]

Clinical quality language is being used for a variety of clinical applications including WHO SMART guidelines where it is used for encoding decision logic and performance indicators. [18] The Centers for Medicare & Medicaid Services adopted CQL for clinical quality measure specifications since 2019. [19] [20]

CQL allows modular and flexible expression of logic and is both human-readable and machine processable. [19]

An implementation of CQL was open sourced and published by the National Committee for Quality Assurance in 2023 with the aim of encouraging adoption of the language. [21]

MLLP

A large portion of HL7 messaging is transported by Minimal Lower Layer Protocol (MLLP), also known as Lower Layer Protocol (LLP) [22] or Minimum Layer Protocol (MLP). [23] For transmitting via TCP/IP, header and trailer characters are added to the message to identify the beginning and ending of the message because TCP/IP is a continuous stream of bytes. [24] Hybrid Lower Layer Protocol (HLLP) is a variation of MLLP that includes a checksum to help verify message integrity. Amongst other software vendors, MLLP is supported by Microsoft, [25] Oracle, [26] Cleo. [27]

MLLP contains no inherent security or encryption but relies on lower layer protocols such as Transport Layer Security (TLS) or IPsec for safeguarding Protected health information outside of a secure network.

Functional EHR and PHR specifications

Functional specifications for an electronic health record.

Message details

The OBR segment

An OBR Segment carries information about an exam, diagnostic study/observation. [28] It is a required segment in an ORM (order message) [29] or an ORU (Observation Result) message. [30]

See also

Related Research Articles

Digital Imaging and Communications in Medicine (DICOM) is a technical standard for the digital storage and transmission of medical images and related information. It includes a file format definition, which specifies the structure of a DICOM file, as well as a network communication protocol that uses TCP/IP to communicate between systems. The primary purpose of the standard is to facilitate communication between the software and hardware entities involved in medical imaging, especially those that are created by different manufacturers. Entities that utilize DICOM files include components of picture archiving and communication systems (PACS), such as imaging machines (modalities), radiological information systems (RIS), scanners, printers, computing servers, and networking hardware.

In the context of health informatics, CCOW or Clinical Context Object Workgroup is a Health Level Seven International standard protocol designed to enable disparate applications to synchronize in real time, and at the user-interface level. It is vendor independent and allows applications to present information at the desktop and portal level in a unified way.

openEHR is an open standard specification in health informatics that describes the management and storage, retrieval and exchange of health data in electronic health records (EHRs). In openEHR, all health data for a person is stored in a "one lifetime", vendor-independent, person-centred EHR. The openEHR specifications include an EHR Extract specification but are otherwise not primarily concerned with the exchange of data between EHR-systems as this is the focus of other standards such as EN 13606 and HL7.

Continuity of Care Record (CCR) is a health record standard specification developed jointly by ASTM International, the Massachusetts Medical Society (MMS), the Healthcare Information and Management Systems Society (HIMSS), the American Academy of Family Physicians (AAFP), the American Academy of Pediatrics (AAP), and other health informatics vendors.

Logical Observation Identifiers Names and Codes (LOINC) is a database and universal standard for identifying medical laboratory observations. First developed in 1994, it was created and is maintained by the Regenstrief Institute, a US nonprofit medical research organization. LOINC was created in response to the demand for an electronic clinical care and management database and is publicly available at no cost.

The Clinical Data Interchange Standards Consortium (CDISC) is a standards developing organization (SDO) dealing with medical research data linked with healthcare, to "enable information system interoperability to improve medical research and related areas of healthcare". The standards support medical research from protocol through analysis and reporting of results and have been shown to decrease resources needed by 60% overall and 70–90% in the start-up stages when they are implemented at the beginning of the research process.

The HL7 Clinical Document Architecture (CDA) is an XML-based markup standard intended to specify the encoding, structure and semantics of clinical documents for exchange. In November 2000, HL7 published Release 1.0. The organization published Release 2.0 with its "2005 Normative Edition".

CEN ISO/IEEE 11073 Health informatics - Medical / health device communication standards enable communication between medical, health care and wellness devices and external computer systems. They provide automatic and detailed electronic data capture of client-related and vital signs information, and of device operational data.

The Continuity of Care Document (CCD) specification is an XML-based markup standard intended to specify the encoding, structure, and semantics of a patient summary clinical document for exchange.

<span class="mw-page-title-main">VistA</span> Health information system

The Veterans Health Information Systems and Technology Architecture (VISTA) is the system of record for the clinical, administrative and financial operations of the Veterans Health Administration VISTA consists of over 180 clinical, financial, and administrative applications integrated within a single shared lifelong database (figure 1).

The GELLO Expression Language was started in 2001 and introduced in 2002; in 2005, GELLO was adopted as an international standard by Health Level Seven International and ANSI for a decision support language. GELLO Release 2 was completed and approved by ANSI in June 2010. The GELLO specifications have been developed in coordination with the HL7 Clinical Decision Support TC (CDSTC)

The Clinical Care Classification (CCC) System is a standardized, coded nursing terminology that identifies the discrete elements of nursing practice. The CCC provides a unique framework and coding structure. Used for documenting the plan of care; following the nursing process in all health care settings.

International HL7 implementations is a collection of known implementations of the HL7 Interoperability standard. These do not necessarily refer to cross-border health information systems.

The Fast Healthcare Interoperability Resources standard is a set of rules and specifications for exchanging electronic health care data. It is designed to be flexible and adaptable, so that it can be used in a wide range of settings and with different health care information systems. The goal of FHIR is to enable the seamless and secure exchange of health care information, so that patients can receive the best possible care. The standard describes data formats and elements and an application programming interface (API) for exchanging electronic health records (EHR). The standard was created by the Health Level Seven International (HL7) health-care standards organization.

Medical device connectivity is the establishment and maintenance of a connection through which data is transferred between a medical device, such as a patient monitor, and an information system. The term is used interchangeably with biomedical device connectivity or biomedical device integration. By eliminating the need for manual data entry, potential benefits include faster and more frequent data updates, diminished human error, and improved workflow efficiency.

Health Level Seven International (HL7) is a non-profit ANSI-accredited standards development organization that develops standards that provide for global health data interoperability.

<span class="mw-page-title-main">Dipak Kalra</span>

Dipak Kalra is President of the European Institute for Health Records and of the European Institute for Innovation through Health Data. He undertakes international research and standards development, and advises on adoption strategies, relating to Electronic Health Records.

The HL7 Consolidated Clinical Document Architecture (C-CDA) is an XML-based markup standard which provides a library of CDA formatted documents. Clinical documents using the C-CDA standards are exchanged billions of times annually in the United States. All certified Electronic health records in the United States are required to export medical data using the C-CDA standard. While the standard was developed primarily for the United States as the C-CDA incorporates references to terminologies and value set required by US regulation, it has also been used internationally.

Clinical data standards are used to store and communicate information related to healthcare so that its meaning is unambiguous. They are used in clinical practice, in activity analysis and finding, and in research and development.

References

Definition of Free Cultural Works logo notext.svg  This article incorporates text from a free content work. Licensed under Creative Commons Attribution-ShareAlike 3.0 license. Text taken from Spronk 2007 .

  1. ↑ Joel Rodrigues (2010). Health Information Systems: Concepts, Methodologies, Tools, and Applications, Volume 1. IGI Global. p. xxxix. ISBN   978-1-60566-988-5.
  2. ↑ "HL7 Primary Standards". Health Level Seven International.
  3. ↑ "HL7 Standards". Health Level Seven International.
  4. ↑ "HL7 FAQs". HL7.
  5. ↑ "Understanding HL7 Messages". iNTERFACEWARE.
  6. ↑ "HL7 Messages and Descriptions". Health Standards.
  7. ↑ "Standards Organizations". Assistant Secretary for Planning and Evaluation (ASPE), Health and Human Services (HHS).
  8. ↑ "HL7 V3 Standard - A High Level Overview". 26 May 2020.
  9. ↑ "HL7 Reference Information Model". HL7.
  10. ↑ "Tools & Resources – V3 Modeling & Methodology Tools". HL7.
  11. ↑ Spronk, René, ed. (16 November 2007). "HL7 Message examples: version 2 and version 3". Ringholm. Ringholm bv.
  12. ↑ Boone, Keith W. (20 May 2011). The CDA Book. Springer. ISBN   9780857293367.
  13. ↑ Dan Munro (2014-03-30). "Setting Healthcare Interop On Fire". Forbes . Retrieved 2014-11-22.
  14. ↑ Kryszyn, Jacek; Smolik, Waldemar T.; Wanta, Damian; Midura, Mateusz; Wróblewski, Przemysław (2023). "Comparison of OpenEHR and HL7 FHIR Standards". International Journal of Electronics and Telecommunications. 69 (1): 47–52. doi:10.24425/ijet.2023.144330 . Retrieved 2024-01-08.
  15. ↑ "Clinical Quality Language (CQL)". cql.hl7.org.
  16. ↑ "1. Introduction". cql.hl7.org.
  17. ↑ "CQL - Clinical Quality Language | eCQI Resource Center". ecqi.healthit.gov.
  18. ↑ "L3 Implementation Guide". www.who.int.
  19. 1 2 Measures management system cms.gov Retrieved 3 April 2024
  20. ↑ Pioneers in Quality. Electronic Clinical Quality Measure (eCQM). Clinical Quality Language (CQL) Basics for Hospitals jointcommission.org
  21. ↑ Raths, David (May 11, 2023). "NCQA Makes Clinical Quality Language Software Open Source". Healthcare Innovation.
  22. ↑ "LLP - Lower Layer Protocol". iNTERFACEWARE.
  23. ↑ "Minimum Layer Protocol". LYNIATE. 13 January 2020.
  24. ↑ Spronk, Rene. "Transport Specification: MLLP, Release 1" (PDF). hl7.org. Health Level Seven Inc. Retrieved 5 September 2022.
  25. ↑ "MLLP Receive and Send Components". MSDN.
  26. ↑ "Oracle Application Server Integration B2B User's Guide, Supported Protocols". Oracle.
  27. ↑ "Which Secure Managed File Transfer Protocol is Right for You?". Cleo. Archived from the original on 2015-06-07. Retrieved 2015-01-23.
  28. ↑ "The HL7 OBR segment". Corepoint Health. Retrieved 2018-11-13.
  29. ↑ "HL7 Glossary of Terms" (PDF). www.hl7.org. Retrieved 2018-11-13.
  30. ↑ "What Is an ORU Message?". Health Standards. Retrieved 2018-11-13.

Critical reviews

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.