HL7 UK OID and Artifact Code Registry
Version: V1r2
Date: 29 Nov 2004
Author: Ian Mansell (Ramsey Systems)
Table of Contents
1 Anticipated changes 2
2 Introduction 2
3 Object Identifiers 2
3.1 What is an OID? 2
3.2 HL7 UK OID Management policy 2
3.3 Main branches of HL7 OIDs 3
4 Artifact Codes 3
4.1 What are Artifact Codes? 3
4.2 Artifact Code context 3
4.3 Artifact Naming Conventions 3
4.3.1 Sub-Sections and Domains 4
4.3.2 Artifact and Document Codes 4
4.3.3 Committee identifier 5
4.3.4 Realm Code 5
4.3.5 Version Number 5
4.4 HL7 UK Artifact Code Management policy 5
5 Bibliography 5
1 Anticipated changes
Allocation of HL7 UK maintained artifact codes
2 Introduction
“HL7 Version 3 defines the use of ISO Object Identifiers, known as OIDs, to identify coding systems. It also suggests their use in the EI and II datatypes to uniquely identify namespaces for identifiers.” [1]
To identify all artifacts (incl. documents) uniquely within HL7 V3, they are assigned an Artifact Code.
This document has been created to give an overview of what OIDs and Artifact Codes are and their use within HL7 UK.
3 Object Identifiers
3.1 What is an OID?
“An Object Identifier is a series of digits delimited in some way.”[3] In the case of HL7 UK OIDs this is achieved using period characters. OIDs are meaningless identifier strings and so should never be used to convey any other form of data.
They are defined in a hierarchical manner with rules that roughly state that once an OID has been assigned to an entity, it has sole discretion to create sub-delegates of this OID. So the entity with the OID “1.2.3” is the authority on what the OID “1.2.3.4” means. [2] [3]
OID definitions may be included in more than one registry.
3.2 HL7UK OID Management policy
Readers wishing to look up OIDs should refer to the HL7UK OID registry that can be found at the following address: http://www.hl7.org.uk/version3group/downloads/OidRootHl7UkOnly.html
HL7UK members wishing to add OIDs that have already been issued but not listed, to the OID registry, should complete a New OID Request form and email it to . This registry is posted on a regular basis for integration with the HL7.org OID registry.
HL7UK members wishing to create their own OIDs should complete a New OID Request form and email it to requesting a new branch.
When an OID branch is allocated to a member, they inherit the responsibility of maintaining unique sub-delegates from that OID. They must also either, provide a persistent URL to a registry for those OIDs that they create, or email the information of the created OIDs and associated information on a New OID Request form to for inclusion in the HL7UK OID registry.
OID registration services are only available to HL7UK members.
3.3 Main branches of HL7 OIDs
It is recommended that members creating their own OIDs use the same structure as that followed by HL7.org and HL7UK. A document containing an outline of this structure can be found here: Main branches of HL7UK OIDs.doc
4 Artifact Codes
4.1 What are Artifact Codes?
Within HL7 an artifact is any structure which needs identification. This identification is provided by Artifact Codes.
Artifact Codes are unique identifier strings used in HL7 V3 that are defined according to a strict standard naming convention. Within this convention Codes are divided so as to be easily identified by Domain, Sub-section and Artifact type (e.g. R-MIM Artifact or V3 Guide Document).
4.2 Artifact Code context
Users of HL7 V3 can make use of both those Artifact Codes that have been accepted into the standard, as well as creating ‘Realm’ specific Codes to satisfy the requirements within a localised context. All ‘Realm’ specific Artifact Codes must comply with the rules set out in HL7 V3.
Those ‘Realm’ specific Codes that are created can either remain as such or be submitted for acceptance into the standard.
4.3 Artifact Naming Conventions
The naming convention followed when constructing HL7 Artifact Codes is as follows:
SSDD_AA000000RRVV[_nn]
The individual components of this naming convention are outlined in the below table [4]:
Segment / Meaning / Valid Values or examplesSS / Sub-Section / PO Operation
PR Practice
CO Common Content
DD / Domain / RX Pharmacy (PORX)
LB Laboratory (POLB)
CT Message Elements
AA / Artifact Code / AR Application Role
DM D-MIM
EX Example
HD HMD
IN Interaction
RM R-MIM
NC Narrative Comment
ST Storyboard
SN Storyboard Narrative
TE Trigger event
MT Message Type
Document Code / BB Backbone
CF Conformance
DT Data Types
DO Domain
GL Glossary
IT ITS
NC Narrative Comment
PB Publication/Domain Database
RI RIM
RP Repository Database
VG V3 Guide
Nn / Committee identifier / A number in the range 000000- 999999
RR / Realm code / UV (Universal), CM (Common) no other realm codes yet allocated
VV / Version Number / A number in the range 00-99
00 is used for in-ballot artifacts
[_nn] / Count / Only applicable for use with multiple examples files of a single artifacts
4.3.1 Sub-Sections and Domains
An example of the use of these codes taken from the above table would be an artifact assigned to the Pharmacy Domain of the Operation Sub-section of the Health and Clinical Management section:
PORX_AA000000RRVV[_nn]
The list of Sub-sections and Domains provided in the above table has been done so for reference as an example set, not an exhaustive list.
4.3.2 Artifact and Document Codes
As you can see from the above table these codes are used to identify document and artifact types.
An example of the use of these codes would be a R-MIM artifact that has been created within the Laboratory Domain of the Operations Sub-section of the Health and Clinical Management section:
POLB_RM000000RRVV[_nn]
4.3.3 Committee identifier
These identifiers are allocated by HL7 and its affiliates. HL7UK has currently allocated the first two digits within the range 00-20 of this identifier for use by NPFIT for use within the UK ‘Realm’.
4.3.4 Realm Code
The only realm codes that are currently present in the HL7 V3 standard are UV (Universal) and CM (Common). These two codes appear in any Artifact Codes that have been accepted into the standard and are therefore not realm specific.
When creating realm specific Artifact Codes these codes are currently replaced with those found in the ISO 3166 Country code table where possible. HL7UK issues identifiers with the ‘Realm’ of UK. Realm codes are still subject to change, as their use has not been universally agreed within HL7.
4.3.5 Version Number
HL7 does not allocate version numbers to un-balloted artifacts.
4.4 HL7UK Artifact Code Management policy
HL7UK members wishing to create their own Artifact Codes should email a request to . If successful the submitter will be issued an Artifact Code range for their use and this will be documented in the HL7UK Artifact registry.
Artifact Code registration services are only available to HL7UK members.
5 Bibliography
[1] [Internet] Health Level Seven Available from: http://www.hl7.org/oid/index.cfm [Accessed 18/11/04]
[2] Mealling, M (Nov. 2000), A URN Namespace of Object Identifiers [Internet], Available from: http://rfc.sunsite.dk/rfc/rfc3001.html [Accessed 18/11/04]
[3] Alvestrand. H ( 10th Feb. 1997), Object Identifiers [Internet] Available from: http://www.alvestrand.no/objectid/ [Accessed 18/11/04]
[4] Hinchley, Andrew (January, 2003), Understanding Version 3, A primer on the HL7 Version 3 Communication Standard, Munich (Germany), Alexander Moench Publishing