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Concept help - Value Domain

A Value Domain describes how to record the measurement of a particular type of data, either using a coded list of values or a description of the possible values. Value Domains can be linked to Data Elements that all share a common way of recording data, and its values can be linked to a Conceptual Domain to provide additional context.

A value domain provides a set of permissible values by which a Data Element can be implemented. Value domains can be enumerated (e.g. Total centimetres NNN) or non-enumerated (e.g. Sex code N).

The union of a specific value domain with a specific Data Element Concept creates a Data Element. For example the data element concept Person—body height can be implemented through union with the Total centimetres NNN value domain.

Permissible values
An expression of a Value Meaning allowed in a specific Value Domain
Permissible values

ISO/IEC 11179 allows for 2 different types of Value Domains - enumerated vs non-enumerated. The distinction between these is that an enumerated value domain is specified by a list of all its Value Meanings, while a non-enumerated value domain is specified by a description rather than a list of all Permissible Values.

  • An example of a enumerated value domain would be a list of 10-year cohorts for recording a persons age:
    • A code of A coresponsing to 0-15 years
    • A code of B coresponsing to 15-30 years
    • A code of C coresponsing to 30-45 years
    • A code of D coresponsing to 45+ years
    Here, every possible value within the set has been explicitly enumerated.
  • An example of a non-enumerated value domain would be an numeric range for recording a persons age, where the number could be any two digit number greater than zero. While there is an implied set of values, these have not been expressly enumerated.
ISO/IEC 11179-3 Section 11.3.2.5

Value_Domain is a class each instance of which models a value domain (3.2.140), a set of permissible values (3.2.96). A value domain provides representation, but has no implication as to the Data Element Concept (3.2.29) with which the values are associated, nor what the values mean.

A Value_Domain is an abstract class which is used to denote a collection of Permissible_Values associated with a Conceptual_Domain (11.3.2.1). A Value_Domain has two possible subclasses: an Enumerated_Value_Domain (11.3.2.6) and a Described_Value_Domain (11.3.2.8). A Value_Domain must be either one or both an Enumerated Valued or a Described_Value_Domain.

Example: 'ISO 3166 Codes for the representation of names of countries' describes seven distinct Value_Domains for the single Conceptual_Domain 'names of countries'. The seven Value_Domains are: 'short name in English', 'official name in English', 'short name in French', 'official name in French', 'alpha-2 code', 'alpha-3 code' and 'numeric code'.

ISO/IEC 11179-3 Section 11.3.2.6

Enumerated_Value_Domain is a class each instance of which models an enumerated value domain (3.2.61), a value domain (3.2.140) that is specified by a list of all its permissible values (3.2.96). The Enumerated_Value_Domain class is a concrete subclass of the abstract class Value_Domain.

ISO/IEC 11179-3 Section 11.3.2.8

Described_Value_Domain is a class each instance of which models a described value domain (3.2.49), a value domain (3.2.140) that is specified by a description or specification, such as a rule, a procedure, or a range (i.e. interval) , rather than as an explicit set of permissible values (3.2.96). It is a concrete subclass of the abstract class Value_Domain. As a subclass of Value_Domain, a Described_Value_Domain inherits the attributes and relationships of the former.

Fields available on this metadata type

Field ISO definition
Name The primary name used for human identification purposes.
Definition Representation of a concept by a descriptive statement which serves to differentiate it from related concepts. (3.2.39)
Is Federated
Is Not Federable
Version Unique version identifier of this metadata item.
References Significant documents that contributed to the development of the metadata item which were not the direct source for the metadata content.
Origin The source (e.g. document, project, discipline or model) for the item (8.1.2.2.3.5)
Comments Descriptive comments about the metadata item (8.1.2.2.3.4)
Deleted The date after which the item has been soft deleted and is no longer visible in the registry
Data Type Datatype used in a Value Domain
Format Template for the structure of the presentation of the value(s)
Maximum Length Maximum number of characters available to represent the Data Element value
Unit Of Measure Unit of Measure used in a Value Domain
Conceptual Domain The Conceptual Domain that this Value Domain which provides representation.
Classification Scheme
Representation Class The classification of types of representations. e.g. 'quantitative, value', 'code', 'text', 'icon'
Description Description or specification of a rule, reference, or range for a set of all values for a Value Domain.

Official Definition

a set of Permissible Values ISO/IEC 11179 - Clause 3.2.140