| Editor | Various Contributors HL7 Publishing Technical Committee |
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The HL7 Glossary provides "core" definitions of words and terms used throughout HL7 standards and documents. These definitions are maintained by the Modeling and Methodology (MnM) and Publishing Technical Committees (TC) and are identified in the glossary as "Core Glossary".
It should be noted that while the Modeling and Methodology and Publishing Technical Committees maintain the glossary definitions, the definitions themselves originate from within the various technical committees and special interest groups and are not constrained or vetted in any way by the MnM or Publishing TCs. It is expected that each committee and its balloters know their business best and that, should an imprecise or incorrect definition be put forward, it will be corrected through the domain balloting process.
It should further be noted that this glossary does not include all the definitions from the Reference Information Model (RIM) as the RIM definitions are already available in the RIM publication and are in context there.
Readers may also note that "core" definitions may be constrained or narrowed within the context of specific domains. For instance, the PM domain includes a definition for Person that is constrained from the RIM definition of Person. In these cases, the PM:Person is perfectly consistent with the RIM:Person, albeit as a specialized subset of the larger group. So while all instances of a PM:Person will also be members of RIM:Persons, not all instances of RIM:Person will fall within the group of PM:Persons.
The MnM and Publishing TCs encourage all members to review the definitions put forward by committees as part of the balloting process with an eye towards correcting and refining them as necessary and appropriate.
For more information refer to the Relationships section of the Version 3 Guide.
association compositionFor more information refer to the Attributes section of the Version 3 Guide.
Attribute (HL7)For more information refer to the Classes section of the Version 3 Guide.
classifier attributeFor more information refer to the Attributes section of the Version 3 Guide.
Clinical statement model HL7Within the “clinical finding” hierarchy is the sub-hierarchy of “disease”. Concepts that are descendants of “disease” are always and necessarily abnormal.
Note: As expected, this definition includes concepts that would be used to represent HL7 Observations. However, it is worth noting that the definition of a finding in SNOMED CT is that it combines the question (see Observable entity) with the answering value.
cloneFor more information refer to the Common Message Element Types section of the Version 3 Guide.
composite aggregationUniversally accepted standardization terminology does not recognize "must". Use "SHALL" to indicate a mandatory aspect or an aspect on which there is no option.
The negatives are SHALL NOT, SHOULD NOT, MAY NOT.
The Publishing Facilitator's Guide requires the Conformance Verbs to be capitalized when they are used to indicate conformance criteria, to differentiate from common usage of the words.
The source for this usage is ANSI.
connectionFor more information refer to the Constraints section of the Version 3 Guide.
Context modelFor more information refer to the Data Types section of the Version 3 Guide.
default valueFor more information refer to the Information Model section of the Version 3 Guide.
domain nameAn expression containing a single concept identifier is referred to as a pre-coordinated expression. An expression that contains two or more concept identifiers is a post-coordinated expression. The concept identifiers within a post-coordinated expression are related to one another in accordance rules expressed in the SNOMED CT Concept Model. These rules allow concepts to be:
Notes: The SNOMED CT compositional grammar provides one way to represent an expression.
The HL7 messaging standard supports communication of SNOMED CT expressions using the “concept descriptor” (CD) data type.
extensibility qualifierFor more information refer to the Vocabulary Domain Qualifiers section of the Version 3 Guide.
Extensible Markup LanguageFor more information refer to the Relationships section of the Version 3 Guide.
generalization hierarchyFor more information refer to the Attributes section of the Version 3 Guide.
IHTSDOFor more information refer to the Implementation Technology Specifications section of the Version 3 Guide.
inclusionFor more information refer to the Information Model section of the Version 3 Guide.
inheritance“Functional” interoperability is the capability to reliably exchange information without error
“Semantic" interoperability is the ability to interpret, and, therefore, to make effective use of the information so exchanged.
In our context, "effective use" means that the information can be used in any type of computable algorithm (appropriate) to that information
ITSFor more information refer to the Classes section of the Version 3 Guide.
object-basedThe HL7 OID Registry is available online.
object identityFor example:
Increased left ventricular end-diastolic pressure is a finding with the value Increased. Left ventricular end-diastolic pressure combined with a separately expressed value such as 95 mmHg also behaves as a finding.
Note: This definition includes concepts that would be used to represent the code attribute of HL7 Observations.
ObservationDiscussion: Structurally, many observations are name-value-pairs, where the Observation.code (inherited from Act) is the name and the Observation.value is the value of the property. Such a construct is also known as a “variable” (a named feature that can assume a value); hence, the Observation class is always used to hold generic name-value-pairs or variables, even though the variable valuation may not be the result of an elaborate observation method. It may be a simple answer to a question or it may be an assertion or setting of a parameter. As with all Act statements, Observation statements describe what was done, and in the case of Observations, this includes a description of what was actually observed (“results” or “answers”); and those “results” or “answers” are part of the observation and not split off into other objects.
Note: This definition refers to the action rather than the outcome of the observation but in the discussion continues to refer to the “results” or “answers” as being a part of the observation. The general idea of an HL7 Observation therefore includes three distinct types of concept from a SNOMED CT perspection “Observable entities” (things that can be measured), “Measurement procedures” (a type of procedure used to make a measurement or observation) and “Clinical finding” (expressing both the name of the observation and its value).
Observations(could be single attribute within CD datatype / single class / multi class) Note: This definition is not stated in HL7 documents but is inferred from usage in relation to particular attributes like Procedure.methodCode and Procedure.targetSiteCode.
Contrast this with the definition of post-coordination in SNOMED CT documentation which refers to a collection of concept identifiers which may be applied to a single HL7 attribute.
Postcoordination (SCT)A combination of concept identifiers used to represent a single clinical idea is referred to as a post-coordinated expression (see expression). Many clinical ideas can also be represented using a single SNOMED CT concept identifier (see pre-coordination).
Some clinical ideas may be represented in several different ways. SNOMED CT technical specifications include guidance of logical transformations that reduce equivalent expressions to a common canonical form.
Example: SNOMED CT includes the following concepts:
Fracture of bone (conceptId= 125605004)
Finding site (conceptId= 363698007)
Bone structure of femur (conceptId= 181255000)
SNOMED CT also includes a pre-coordinated concept for this procedure
Fracture of femur (conceptId= 71620000)
It is possible to represent “fracture of femur” in different ways: 71620000 (pre-coordinated expression) 125605004 : 363698007 = 181255000 (post-coordinated expression).
Note: In an HL7 representation a SNOMED CT expression is represented in a single HL7 attribute using the HL7 CD (Concept Descriptor) data type.
Pre-coordinationNote: This definition is not stated in HL7 documents but is inferred from usage in relation to particular attributes like Procedure.methodCode and Procedure.targetSiteCode.
Contrast this with the definition of pre-coordination in SNOMED CT documentation which implies a single concept identifier is used to represent a meaning.
Precoordination (SCT)Representation of a clinical idea using a single concept identifier.
A single concept identifier used to represent a specific meaning is referred to as a pre-coordinated expression (see expression). SNOMED CT also allows the use of post-coordinated expressions (see post-coordination) to represent a meaning using a combination of two or more concept identifiers.
However, including commonly used concepts in a pre-coordinated form makes the terminology easier to use.
For examples see post-coordination.
predicate referenceDiscussion: Applied to clinical medicine, procedure is but one among several types of clinical activities such as observation, substance-administrations, and communicative interactions (e.g. teaching, advice, psychotherapy, represented simply as Acts without special attributes). Procedure does not subsume those other activities nor is procedure subsumed by them. Notably Procedure does not comprise all acts of whose intent is intervention or treatment. Whether the bodily alteration is appreciated or intended as beneficial to the subject is likewise irrelevant, what counts is that the act is essentially an alteration of the physical condition of the subject.
Note: This definition and the associated discussion exclude many activities which are subsumed by the more general sense of the word “procedure” which is used in the SNOMED CT definition.
Procedure (SCT)Note: As expected, this definition includes concepts that would be used to represent HL7 Procedures. However, it also includes measurement procedures and actions that involve administration of a substance. Therefore, the code attribute of many HL7 Observations and SubstanceAdministration Acts may also be expressed using concepts from the SNOMED procedures hierarchy.
propertyFor more information refer to the Vocabulary Domain Qualifiers section of the Version 3 Guide.
receiver responsibilityFor more information refer to the Information Model section of the Version 3 Guide.
Refined Message Information ModelFor more information refer to the Information Model section of the Version 3 Guide.
requiredFor more information refer to the Dynamic Behavior section of the Version 3 Guide.
state attributeFor more information refer to the Attributes section of the Version 3 Guide.
state diagramFor more information refer to the Dynamic Behavior section of the Version 3 Guide.
state transition modelFor more information refer to the Vocabulary section of the Version 3 Guide.
vocabulary domainFor more information refer to the Vocabulary Domains section of the Version 3 Guide.
vocabulary domain qualifierFor more information refer to the Vocabulary Domain Qualifiers section of the Version 3 Guide.
vocabulary domain specificationThe three-part schema specification issued by the W3C
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