ISO/IEC 11179-1:1999

INTERNATIONAL ISO/IEC
STANDARD 11179-1
First edition
1999-12-01
Information technology — Specification
and standardization of data elements —
Part 1:
Framework for the specification and
standardization of data elements
Technologies de l'information — Spécification et normalisation des
éléments de données —
Partie 1: Cadre pour la spécification et la normalisation des éléments de
données
Reference number
©
ISO/IEC 1999
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ii
Contents Page
1 Scope . 1
2 Normative References . 1
3 Definitions . 1
4 Abbreviations . 9
5 Methodology Independence . 10
6 Fundamental Concepts of Data Elements . 10
7 Relationship of Data Elements to Other Data Concepts . 11
8 Overview of ISO/IEC 11179, Parts 1-6 . 12
Annex A Fundamental Concepts of Data Representation and Management .17
Annex B Metadata and Data Elements . 30
Bibliography . 32
© ISO/IEC 1999 – All rights reserved
iii
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical Commission) form the
specialized system for worldwide standardization. National bodies that are members of ISO or IEC participate in the
development of International Standards through technical committees established by the respective organization to deal with
particular fields of technical activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other
international organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the work.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
In the field of information technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1. Draft
International Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the national bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this part of ISO/IEC 11179 may be the subject of patent
rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
International Standard ISO/IEC 11179-1 was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 32, Data management services.
ISO/IEC 11179 consists of the following parts, under the general title Information technology — Specification and
standardization of data elements:
� Part 1:Framework for the specification and standardization of data elements
� Part 2: Classification for data elements
� Part 3: Basic attributes of data elements
� Part 4: Rules and guidelines for the formulation of data definitions
� Part 5: Naming and identification principles for data elements
� Part 6: Registration of data elements
Annexes A and B of this part of ISO/IEC 11179 are for information only.
© ISO/IEC 1999 – All rights reserved
iv
Introduction
Background
Humans are aware of anything that exists in the natural world through its properties. Data represents the properties of these
things. Specification of data elements, the basic units of data, involves documenting relevant characteristics of each data
element to ensure its representation of the natural world item is consistent and accurate. Data that has been carefully specified
and standardized greatly enhances its usefulness and shareability across systems and environments. Sharing data involves the
ability to locate desired data, retrieve the data, and to exchange the data with others. When data elements are well documented
according to ISO/IEC 11179 and the documentation is managed in a Data Element Registry, finding and retrieving them from
disparate databases as well as sending and receiving them via electronic communications are made easier.
The recognition and standardization of data elements used in communications through automated information processing
systems is an ongoing and essential activity. The success of this activity and its application throughout the world is of vital
importance if international communications among governments, businesses, and scientific communities are to be improved.
The primary data sharing and standardization problems addressed by the development of ISO/IEC 11179 include, but are not
limited to the following:
� A lack of mechanisms for enabling global data acquisition and interchange, particularly across application
areas;
� Unique global identifiers for standard data elements currently do not exist;
� Documentation of data element characteristics is inadequate to support fully automated sharing of data,
including locating, retrieving, and exchanging the data;
� There is a lack of uniform guidance for identification, development, and description of data elements;
� Finding and retrieving a specific standard data element among thousands or millions is difficult or
impossible;
� No universal means for organizing standard data elements exists;
� While data is sometimes standardized within an organization, there are few common data standards between
organizations;
� Exchange of data among organizations results in a proliferation of customized data interchange
representations;
� Data definitions and descriptions are not sufficiently precise to support reuse or multiple users of data;
� Current inventory structures for reducing logical data redundancies are inadequate;
� Global implementation of Electronic Data Interchange (EDI) is impeded by a lack of standard data elements;
standard data elements are needed for the content of EDI messages.
To facilitate global electronic communications, the International Standards community has been working diligently to define
an Open Systems Interconnection Environment (OSIE) within which diverse computer hardware and applications could share
information. Standards have been proposed or defined for three (hardware, software, and communications) of the four
(hardware, software, communications, and data) basic components required for open information processing systems. ISO/IEC
11179 for data specification, the fourth basic component for open information systems, provides a mechanism for enabling
data to be shared in the OSIE.
For systems to be truly open, data must be portable and shareable within and among these various application environments,
which span localized and distributed networks. For data to be shareable, both the users and owners of data must have a
common understanding of its meaning, representation, and identification. To understand the meaning of any data, the
descriptions of the data must be available to the users from, for example, a Data Element Registry. Data must be adequately
described and users must have a convenient way to obtain these descriptions. Data Element Registries provide a way to
© ISO/IEC 1999 – All rights reserved
v
organize the content and representation of data elements so that data descriptions are consistently specified and can be easily
located by data designers and users. Uniform specification of data facilitates data retrieval, data exchange, and consistent use
of data throughout the Software Development Life Cycle. The units of information with normalized meanings and formats are
known as "standardized data elements."
Purpose of ISO/IEC 11179
ISO/IEC 11179 describes the standardizing and registering of data elements to make data understandable and shareable. Data
element standardization and registration as described in ISO/IEC 11179 allow the creation of a shared data environment in
much less time and with much less effort than it takes for conventional data management methodologies.
The purpose of ISO/IEC 11179 is to give concrete guidance on the formulation and maintenance of discrete data element
descriptions and semantic content (metadata) that shall be used to formulate data elements in a consistent, standard manner. It
also provides guidance for establishing a data element registry.
Although motivated by the desire for the open exchange of data throughout the international communities by electronic
information interchanges, ISO/IEC 11179:
� facilitates acquisition and registration of data;
� expedites access and use of data;
� simplifies data manipulation by intelligent software by enabling manipulation of data based on
characteristics described by metadata;
� enables the development of a data representation metamodel for CASE tools and repositories; and
� facilitates electronic data interchange and data sharing.
ISO/IEC 11179 benefits the communication of data among information systems and people:
� within an organization;
� among different organizations; and
� crossing all levels of software and hardware, and geographic, organizational and political boundaries.
Metadata about data elements is stored in a data element registry. A data element registry supports data sharing with
descriptions of data. Registration is the process of documenting metadata to support data shareability. Registration should be
carried out at the data element level to promote and maximize semantic value. ISO/IEC 11179 enables the end user to interpret
the intended meaning confidently, correctly, and unambiguously.
Users of ISO/IEC 11179
For users and managers of data, ISO/IEC 11179 specifies a basic set of data element characteristics necessary to share data. It
places special emphasis on important data element characteristics such as identifiers, definitions, and classification categories.
ISO/IEC 11179 describes a data element registry to assist users of shared data to have a common understanding of a data
elements meaning, representation, and identification. If data values are received, the user can discover the exact meaning of
the data received. If users wish to retrieve data values from a database, they can identify the type of data desired.
For systems analysts and data stewards, ISO/IEC 11179 provides a way to reuse a data element that meets a need, or to design
a new data element if one does not already exist. Even before the user accesses data elements in a database, data stewards and
systems analysts must have a way to identify and describe data logically so that they do not inadvertently introduce
inconsistent values of data. If systems analysts are to create products that share data, they must first be aware whether or not a
data element with the required characteristics already exists. If it does, they should use it. If the systems analysts choose to
replicate the data element, they must represent data elements containing the same information in the same manner. If a data
element with exactly the same characteristics does not already exist, a data steward needs to design the data element and make
its description available to software developers. ISO/IEC 11179 aids in the development of precise descriptions of data
© ISO/IEC 1999 – All rights reserved
vi
elements. Data elements that have been formulated according to the principles in this multi-part International Standard enable
interchangeability and retrieval regardless of the information processing system or telecommunication protocols employed.
For software developers, ISO/IEC 11179 provides means to assure data coherence. A registry can serve software developers by
enabling the consistent use of data throughout the Software Development Life Cycle (SDLC). A registry will provide the
mechanisms for managing data elements and for ensuring their traceability between SDLC phases.
For developers of a data dictionary, data element registry, CASE tool, and other data management software, ISO/IEC 11179
provides the basis for designing a metamodel necessary to enable the capture, storage, management, and exchange of the data
element metadata.
© ISO/IEC 1999 – All rights reserved
vii
INTERNATIONAL STANDARD ISO/IEC 11179-1:1999(E)
Information technology — Specification and standardization of data
elements —
Part 1:
Framework for the specification and standardization of data elements
1. Scope
ISO/IEC 11179 specifies basic aspects of data element composition, including metadata. It applies to
formulation of data element representations and meaning as shared among people and machines; it does not
apply to the physical representation of data as bits and bytes at the machine level.
This part of ISO/IEC 11179 provides the context for associating the individual parts and is the foundation for a
conceptual understanding of data elements.
2. Normative References
The following normative documents contain provisions which, through reference in this text, constitute
provisions of this part of ISO/IEC 11179. For dated references, subsequent amendments to, or revisions of, any
of these publications do not apply. However, parties to agreements based on this part of ISO/IEC 11179 are
encouraged to investigate the possibility of applying the most recent editions of the normative documents
indicated below. For undated references, the latest edition of the normative document referred to applies.
Members of ISO and IEC maintain registers of currently valid International Standards.
ISO Standards Handbook 10, Data Processing - Vocabulary, 1982.
ISO 704:1987, Principles and methods of terminology.
ISO 1087, Terminology - Vocabulary.
ISO 2382-4:1987, Information processing systems - Vocabulary - Part 4: Organization of data.
ISO/IEC 10241:1992, International terminology standards - Preparation and layout.
ISO/IEC 11179-2, Information technology - Specification and standardization of data elements - Part 2:
Classification for data elements.
ISO/IEC 11179-3:1994, Information technology - Specification and standardization of data elements - Part 3:
Basic attributes of data elements.
ISO/IEC 11179-4:1995, Information technology - Specification and standardization of data elements - Part 4:
Rules and guidelines for the formulation of data definitions.
ISO/IEC 11179-5:1995, Information technology - Specification and standardization of data elements - Part 5:
Naming and identification principles for data elements.
ISO/IEC 11179-6:1997, Information technology - Specification and standardization of data elements - Part 6:
Registration of data elements.
3. Definitions
For the purposes of ISO/IEC 11179, the following terms are defined in the table below. An X under the column
heading for a Part indicates that the term is defined in that Part and used in other clauses there. Each word that
appears in bold in the definition of a term is a term defined elsewhere in this clause. Words that appear in
regular type assume their commonly understood definitions. Some words (e.g. representation) are used both
ways. There are instances where two or more terms appear next to each other in a definition, giving the
appearance that a new term is undefined. There is no ambiguity in determining the actual terms in these cases.
© ISO/IEC 1999 – All rights reserved 1

Part Number
Number Term Definition 1 2 3 4 5 6
3.1 administered A component for which administrative
X
component: attributes are collected.
3.2 administrative status: A designation of the position in the processing
X X
life-cycle of a registration authority for
handling registration requests.
3.3 attribute: A characteristic of an object or entity. X X X X X X
3.4 attribute value: A representation of an instance of an attribute. X
3.5 certified data element: A recorded data element that has met the
X X
quality requirements specified in ISO/IEC
11179.
3.6 classification scheme: An arrangement or division of objects into
X X X
groups based on characteristics that the objects
have in common, e.g., origin, composition,
structure, application, function, etc.
3.7 classification scheme A component of content in a classification
item: scheme. This may be a node in a taxonomy or X
ontology, a term in a thesaurus,etc.
3.8 classified component: Any component of a data element that may be
classified in one or more classification X
schemes. These components include the object
class, property, representation class, data
element concept, value domain,and data
element.
3.9 comments: Remarks on the data element. X X
3.10 concept: A unit of thought constituted through X X X
abstraction on the basis of characteristics
common to a set of objects. [ISO 1087]
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Term Definition 1 2 3 4 5 6
3.11 context: A designation or description of the application
X X X
environment or discipline in which a name is
applied or from which it originates.
3.12 data: A representation of facts, concepts, or
X X X X
instructions in a formalized manner, suitable for
communication, interpretation, or processing by
humans or by automatic means. [ISO 2382-4]
3.13 data dictionary: A database used for data that refers to the use
X X X
and structure of other data; that is, a database
for the storage of metadata [ANSI X3.172-
1990]. See also data element dictionary.
3.14 data element: Aunitof data for which the definition,
X X X X X X
identification, representation, and permissible
values are specified by means of a set of
attributes.
3.15 data element concept: A concept that can be represented in the form
X X X X X
of a data element, described independently of
any particular representation.
3.16 data element An information resource that lists and defines X X X
dictionary: all relevant data elements. See also register.
3.17 data element facet: Any aspect of a data element that is subject to
X
classification. This includes object class,
property, representation,and data element
concept.
3.18 data element name: A single or multi-word designation used as the X
primary means of identification of data
elements for humans.
3.19 data element registry: An information resource kept by a registration
authority that describes the meaning and X
representational form of data elements,
including registration identifiers, definitions,
names, value domains, metadata and
administrative attributes, etc. See also
register.
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Term Definition 1 2 3 4 5 6
3.20 data element value: A value out of a set of permissible values
X X
pertaining to a data element. See also data
value.
3.21 data identifier (DI): An identifier of a data element (a string of
X X
characters or other graphic symbols) assigned
by a registration authority.
3.22 data item: Oneoccurrenceofa data element. X
3.23 data model: A description of the organization of data in a X
manner that reflects an information structure.
3.24 data steward: A person or organization delegated the
X
responsibility for managing a specific set of
data resources.
3.25 datatype: The format used for the collection of letters,
X
digits, and/or symbols, to depict values of a
data element, determined by the operations
that may be performed on the data element.
3.26 datatype of data A set of distinct values for representing the X X
element values: data element value.
3.27 data value: An element of a value domain. X
3.28 definition: A word or phrase expressing the essential
X X X X
nature of a person or thing or class of persons or
things: an answer to the question "what is x?"
or"whatisan x?";astatementofthe meaning
of a word or word group [Webster's Third New
International Dictionary of the English
Language Unabridged, 1986]. Statement that
expresses the essential nature of a data element
and permits its differentiation from all other
data elements.
3.29 domain: The set of possible data values of an attribute. X X X
[ISO/IEC 2382]. See also value domain.
© ISO/IEC 1999 – All rights reserved
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Term Definition 1 2 3 4 5 6
3.30 entity: Any concrete or abstract thing of interest,
X X
including associations among things. [ISO/IEC
2382]. Also see object class.
3.31 enumerated domain: A value domain that is specified by a list of all X
permissible values.
3.32 form of representation: Name or description of the form of
X X
representation for the data element.e.g.
'quantitative value, 'code', 'text', 'icon'. See also
representation term.
3.33 identifier: A language independent unique identifier of a
X X X X X X
data element within a registration authority.
See also data identifier. An unambiguous
name for an object within a given context.
3.34 information: (In information processing): Knowledge
concerning objects, such as facts, events, X
things, processes, or ideas, including concepts,
that within a certain context has a particular
meaning. [ISO/IEC 2382]
3.35 information The process of sending and receiving data in
X X
interchange: such a manner that the information content or
meaning assigned to the data is not altered
during the transmission.
3.36 international An internationally unique identifier for a data
X
registration data element.
identifier (IRDI):
3.37 keyword: One or more significant words used for retrieval X X X
of data elements.
3.38 layout of The layout of characters in data element X X
representation: values expressed by a character string
representation.
3.39 lexical: Pertaining to words or the vocabulary of a
X X
language as distinguished from its grammar and
construction.
© ISO/IEC 1999 – All rights reserved
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Term Definition 1 2 3 4 5 6
3.40 maximum size of data The maximum number of storage units (of the
X X
element values: corresponding datatype)torepresentthe data
element value.
3.41 metadata: Data that defines and describes other data. X
3.42 minimum size of data The minimum number of storage units (of the
X X
element values: corresponding datatype)torepresent the data
element value.
3.43 name: The primary means of identification of objects
X X X X X X
and concepts for humans. A single or multi-
word designation assigned to a data element.
3.44 object: Any part of the conceivable or perceivable X
world. [ISO 1087].
3.45 object class: Aset of objects. A set of ideas, abstractions, or
X
things in the real world that can be identified
with explicit boundaries and meaning and
whose properties and behavior follow the same
rules.
3.46 object class term: A component of the name of a data element
X X
which represents the object class to which it
belongs; e.g. "employee".
3.47 permissible data The set of representations of permissible
X X
element values: instances of the data element, according to the
representation form, layout, datatype,
maximum size,and minimum size specified in
the corresponding attributes. The set can be
specified by name, by reference to a source, by
enumeration of the representation of the
instances, or by rules for generating instances.
3.48 property: A peculiarity common to all members of an X
object class.
© ISO/IEC 1999 – All rights reserved
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Term Definition 1 2 3 4 5 6
3.49 property term: A component of the data element name which
X X
expresses a property of an object class.(A
component of the name of a data element
which expresses the category to which the data
element belongs.)
3.50 qualifier: A term that helps define and render a concept X
unique.
3.51 qualifier term: A word or words which help define and X
differentiate a name within the database.
3.52 recorded data element: A submitted data element which contains all
X X
mandatory attributes and has been recorded
but the contents may not meet the quality
requirements specified in other parts of
ISO/IEC 11179.
3.53 register: A set of files (paper, electronic, or a
X
combination) containing the assigned data
elements and the associated information. See
also data element registry.
3.54 registration: The assignment of an unambiguous identifier
X X
to a data element in a way that makes the
metadata about those data elements available
to interested parties.
3.55 registration applicant: An organization, individual, etc, which requests
X
the assignment of an identifier from a
registration authority.
3.56 registration authority An organization authorized to register data
(RA): elements or other objects. X X X X
3.57 registration authority An identifier assigned to a registration X X X X
identifier (RAI): authority.
3.58 registration status: A designation of the position in the X X X
registration life-cycle of a data element.
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Term Definition 1 2 3 4 5 6
3.59 related data reference: A reference between a data element and any X X
related data.
3.60 representation: The combination of a value domain, datatype,
X
and, if necessary, a unit of measure or a
character set.
3.61 representation category: Type of symbol, character, or other designation X X
used to represent a data element.
3.62 representation term: A component of a data element name which
X X
describes the form of representation of the
data element.
3.63 responsible The organization or unit within an organization
X X
organization: that is responsible for the contents of the
mandatory attributes by which the data
element is specified.
3.64 semantics: The branch of linguistic science which deals X X
with the meaning of words (Webster).
3.65 separator: A symbol or space enclosing or separating X
components within a name; a delimiter.
3.66 standardized data A certified data element within the data X X
element: element registry that is preferred for use.
3.67 structure set: A method of placing objects in context,
X
revealing relationships to other objects.
Examples include entity-relationship models,
taxonomies, and ontologies.
3.68 submitting organization The organization or unit within an organization
X X
(SO): that has submitted the data element for
addition, change, cancellation, or withdrawal in
the data element registry.
3.69 synonymous name: Single or multi-word designation that differs
X X
from the given name, but represents the same
data element concept.
© ISO/IEC 1999 – All rights reserved
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Term Definition 1 2 3 4 5 6
3.70 syntax: The structure of expressions in a language, and
X X
the rules governing the structure of a language.
The relationships among characters or groups of
characters, independent of their meanings or the
manner of their interpretation and use.
3.71 taxonomy: Classification according to presumed natural X X
relationships among types and their subtypes.
3.72 term: Designation of a defined concept in a special
language by a linguistic expression. [ISO/IEC X
1087]
3.73 thesaurus: A controlled vocabulary arranged in a given
X X
order in which relationships among terms are
displayed and identified.
3.74 type of relationship: An expression that characterizes the X X
relationship between the data element and
related data.
3.75 value domain: A set of permissible values. X
3.76 version: The identification of an issue of a data element
X X
specification in a series of evolving data
element specifications within a registration
authority.
3.77 version identifier (VI): An identifier assigned to a version under
X X X
which a data element registration is submitted
or updated.
NOTE: Part 5, same as version.
4. Abbreviations
CASE -- Computer-Aided Software Engineering
EDI -- Electronic Data Interchange
ERD -- Entity-relationship Diagram
© ISO/IEC 1999 – All rights reserved
IEC -- International Electrotechnical Commission
ISO -- International Organization for Standardization
JTC1 -- Joint Technical Committee 1
OSIE -- Open Systems Interconnection Environment
RA -- Registration Authority
RDBMS -- Relational Database Management System
SC32 -- ISO/IEC JTC1/Sub-committee 32
SDLC -- Software Development Life Cycle
5. Methodology Independence
It is recognized that different methodologies are used to derive application-oriented data elements. Data
modeling, alone, has numerous methodological approaches (e.g., Information Engineering and object-oriented)
for identifying and forming data elements. This data specification standard, including its six parts, is
independent of any data element derivation methodology or technique. Since the standard applies to all data
elements, it can be used equally well in any approach to data element creation.
6. Fundamental Concepts of Data Elements
For the purposes of ISO/IEC 11179, a data element is composed of three parts as follows:
� the object class is a set of ideas, abstractions, or things in the real world that can be identified with
explicit boundaries and meaning and whose properties and behavior follow the same rules;
� the property is a peculiarity common to all members of an object class; and
� the representation describes how the data are represented, i.e. the combination of a value domain,
datatype, and, if necessary, a unit of measure or a character set.
Object classes are the things about which we wish to collect and store data. Examples of object classes are cars,
persons, households, employees, orders, etc. However, it is important to distinguish the actual object class from
its name. Ideas simply expressed in one natural language (English), may be more difficult in another (Chinese),
and vice-versa. For example, "women between the ages of 15 and 45 who have had at least one live birth in the
last 12 months" is a valid object class not easily named in English. Nevertheless, object classes can be formed
by combining two or more other object classes. This example combines the notions of "people between the ages
of 15 and 45" with "women who have had at least one live birth in the last 12 months".
Properties are what humans use to distinguish or describe objects. Examples of properties are color, model, sex,
age, income, address, price, etc. Again, properties may need to be described using multiple words, depending on
the natural language in use.
The most important aspect of the representation part of a data element is the value domain. A value domain is a
set of permissible (or valid) values for a data element. For example, the data element representing annual
household income may have the set of non-negative integers (with units of dollars) as a set of valid values.
This is an example of a non-enumerated domain. Alternatively, the valid values may be a pre-specified list of
categories with some identifier for each category, such as:
Part 5 of ISO/IEC 11179 specifies the inclusion of a representation term in the name of a data element, so annual household
income is not a complete data element name. The omission is intentional.
© ISO/IEC 1999 – All rights reserved
1 $0 - $15,000
2 $15,001 - $30,000
3 $30,001 - $60,000
4 $60,001 - +
This value domain is an example of an enumerated domain. In both cases, the same object class and property
combination - the annual income for a household - is being measured.
The combination of an object class and a property is a data element concept (DEC). A DEC is a concept that
can be represented in the form of a data element, described independently of any particular representation. In
the examples above, annual household income actually names a DEC, which has two possible representations
associated with it. Therefore, a data element can also be seen to be composed of two parts: a data element
concept and a representation.
Figure 6-1 illustrates the ideas conveyed in this section.
Figure 6-1: Data Element Structure
7. Relationship of Data Elements to Other Data Concepts
Figure 7-1 provides a simplified representation of levels of data to illustrate those levels in which data elements
lie. Data elements appear in databases, files, and transactions sets. Data elements are the fundamental units of
data an organization manages, therefore they must be part of the design of databases and files within the
organization and all transaction sets the organization builds to communicate data to other organizations.
Within the organization, databases or files are composed of records, segments, tuples, etc. which are composed
of data elements. The data elements themselves contain various kinds of data that include characters, images,
sound, etc.
© ISO/IEC 1999 – All rights reserved
When the organization needs to transfer data to another organization, data elements are the fundamental units
that make up the transactions sets. Transactions occur primarily between databases or files, but the structure (i.e.
the records or tuples) of the files and databases don't have to be the same across organizations. So, the common
unit for transferring information (data plus understanding) is the data element.
Figure 7-1: Data Elements in Levels of Data
8. Overview of ISO/IEC 11179, Parts 1-6
8.1. Introduction of Parts
This clause introduces each part of the multi-part standard ISO/IEC 11179. It summarizes the main points and
discusses the importance of each.
8.1.1 Part 1
ISO/IEC 11179-1, Framework for the Specification and Standardization of Data Elements, introduces and
discusses fundamental ideas of data elements essential to the understanding of this set of standards and provides
the context for associating the individual parts of ISO/IEC 11179.
8.1.2 Part 2
Classification for Data Elements, ISO/IEC 11179-2, provides procedures and techniques for associating data
element concepts and data elements with classification schemes for object classes, properties and
representations.
© ISO/IEC 1999 – All rights reserved
These procedures and techniques shall assist Registration Authorities in applying classification schemes that
enable them to perform activities such as:
� analyze object classes, data element concepts, and data elements;
� make comparisons within the following categories: object classes, data element concepts, and
data elements;
� reduce the variety of data element concepts and data elements;
� define and identify data element concepts and data elements unambiguously;
� assist in the analysis of data elements for the purpose of assigning registration status;
� retrieve data element concepts and data elements from a data element registry;
� recognize relationships among data element concepts and data elements.
ISO/IEC 11179-2 develops a set of principles, methods, and procedures for specifying what is needed (at a
minimum) in a taxonomy/ontology for description of object class, property, representation, data element
concepts, and data elements (herein called "information elements"). This includes the need for names, non-
intelligent identifiers, definitions, and other things that can be captured as attributes. ISO/IEC 11179-2 shows
how to go from a taxonomy to attributes and how to use the attributes specified in ISO/IEC 11179-3 as well as
other attributes that are needed. Taxonomies are provided in an informative annex. A suggested set of qualifiers
that could be applied to the property information element and a set of qualifiers for the representation
information element are provided. The qualifier sets are accompanied with an explanation of how to address
synonym and homonym problems. ISO/IEC 11179-2 also shows how information elements relate to taxonomies
and how the pertinent taxonomic information can be used to describe the above information elements.
8.1.3 Part 3
Basic Attributes of Data Elements, ISO/IEC 11179-3, specifies attributes of data elements. It is limited to a set
of basic attributes for data elements, independent of their usage in application systems, databases, data
interchange messages, etc.
The increased use of data processing and electronic data interchange heavily relies on accurate, reliable,
controllable, and verifiable data recorded in databases. One of the prerequisites for a correct and proper use and
interpretation of data is that both users and owners of data have a common understanding of the meaning and
representation of the data elements. To guarantee a shared view of data elements, a number of basic attributes
have to be defined.
The basic attributes specified are applicable for the following main activities:
a) definition and specification of the contents of data element dictionaries;
b) design and specification of application-oriented data models, databases, and messages for data
interchange;
c) actual use of data in communications and information processing systems;
d) interchanging or referencing among various collections of data elements.
Basic means that they are essential in specifying a data element completely enough to ensure that it will be
applicable for a variety of functions, such as:
� design of information processing systems;
� retrieval of data from databases;
© ISO/IEC 1999 – All rights reserved
� design of EDI-messages for data interchange;
� maintenance of data element dictionaries;
� data management;
� dictionary design;
� dictionary control;
� use of information processing systems.
Basic also implies that they are independent of any:
� application environment;
� function of a data element (e.g., qualifier, indicator);
� level of abstraction of the meaning (e.g., a representation of a generic concept like 'name of a
person' or a representation of a specific concept like 'name of the driver of a truck');
� grouping of data elements;
� method for designing information processing systems or data interchange messages;
� data element registry system.
Basic does not imply that all attributes specified in ISO/IEC 11179-3 are required in all cases. Distinction is
made between those basic attributes that are:
� mandatory - always required ;
� conditional: required to be present under certain specified conditions;
� optional - allowed but not required.
8.1.4 Part 4
Rules and Guidelines for the Formulation of Data Definitions, ISO/IEC 11179-4, provides guidance on how to
develop unambiguous data element definitions. A number of specific rules and guidelines are presented in
ISO/IEC 11179-4 that specify exactly how a data element definition should be formed. A precise, well-formed
definition is one of the most critical requirements for shared understanding of a data element; well-formed
definitions are imperative for the exchange of information. Only if every user has a common and exact
understanding of the data element can it be exchanged trouble-free.
8.1.5 Part 5
Naming and Identification Principles for Data Elements, ISO/IEC 11179-5, provides guidance for the
identification of data elements. Identification is a broad term for designating, or identifying, a particular data
element. Identification can be accomplished in various ways, depending upon the use of the identifier.
Identification includes the assignment of numerical identifiers that have no inherent meanings to humans; icons
(graphic symbols to which meaning has been assigned); and names with embedded meaning, usually for human
understanding, that are associated with the data element's definition and value domain.
Required to record data elements. ISO/IEC 11179-3 does not address recording the subsets of attributes required to record
data element concepts.
© ISO/IEC 1999 – All rights reserved
Names are semantic, natural language labels given to data elements, and variations of these labels serve different
functions. Some names are for human usage and comprehension; some names are for use in a particular physical
system environment. Names are often user established and vary from one user to the other. The principles in
ISO/IEC 11179-5 describe the various functions of names and how names are used. One and only one identifier
is required for each data element within a Registration Authority. The identifier does not change as long as the
meaning and type of representation of the data element remains unchanged. Identifiers are unique only within a
Registration Authority. ISO/IEC 11179 does not specify the format or the content of identifiers.
Each data element may be given many names - each with meaning within a particular context. Structured names
may be registered for data management, a preferred name may be specified by the enterprise, many common
names may be familiar to various user groups, shortened names may be registered for software applications, etc.
A naming convention is enforced within each context. This convention may be different between contexts.
Along with each name for a data element, the description of the context must be provided.
One type of structured name may be derived from the classification scheme described in ISO/IEC 11179-2. The
components of this name come from the three classification taxonomies: Object Class, Property, and
Representation. By assembling the name of each taxon along with some descriptive qualifiers, a data element
name can be built. This name can be valuable for assisting the user to find or place a data element in a taxonomy
intuitively. However,
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