Section 1d: Version 2 (V2)
Section 4: Rules and References
XML Encoding Rules (HL7 Version 2: XML Encoding Syntax, Release 1)
DESCRIPTION
This document describes how to use XML for Version 2.x (V2) messages. Even with the release of HL7 Version 3 (V3), HL7 V2.xml is needed to support the large base of existing systems that employ V2. This document does not replace the standard sequence oriented encoding rules that use “vertical bars” and other delimiters (so called “vertical bar encoding”), but rather provides an alternative way of encoding. Message definitions given in the Version 2.3.1 and 2.4 standards are also untouched. This document does not modify the message definitions, only the way they are encoded.
ALTERNATIVE NAMES
XML Encoding Rules (HL7 Version 2: XML Encoding Syntax, Release 1) may also go by the following names or acronyms:
TARGETS
- Healthcare IT Vendors
- Healthcare Providers
BENEFITS
- Confers the ability to parse and validate messages with any XML parser
- Promotes adoption of generic messaging encoding, which in turn promotes cost and error reduction
- Helps prepare healthcare increase data interchange commonality with other business areas
- Helps vendors and providers transition from HL7 V2 family of standards to V3 by encouraging the early retooling of applications to support XML interface
IMPLEMENTATIONS/CASE STUDIES
- 95 of US healthcare organizations use HL7 V2.x
- 35 countries have HL7 V2.x implementations
DEVELOPMENT BACKGROUND
HL7 V2 XML Encoding Syntax was approved by the American National Standards Institute (ANSI) as an American National Standard in June 2003 and reaffirmed in 2010. This specification, informally known as HL7 V2.xml, defines the Extensible Markup Language (XML) encoding rules for traditional HL7 V2 message content. It primarily addresses the expression of HL7 V2 messages in XML as an alternative to the traditional “vertical bar” encoding, and describes the underlying rules and principles. XML schema definitions are provided for all V2 message types, including the corresponding data type descriptions necessary for this specification. Due to their greater expressiveness, schemas are the preferred way to describe a set of constraints on message instances. Document Type Definitions (DTDs) are also provided as an informative appendix.
RELATED DOCUMENTS
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XML Encoding Rules (HL7 Version 2: XML Encoding Syntax, Release 1) |
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BALLOT TYPES
- Normative
STATUS DATE
2010-02-18RESPONSIBLE WORK GROUP
PRODUCT TYPES
- ANSI-approved
- Encoding Syntax
FAMILY
- V2
CURRENT STATE
- Retired
REALM
- Universal