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Controlled Vocabularies - Overview Table of Latest Versions

What is a controlled vocabulary?

The DDI Controlled Vocabularies Group (CVG) has created a set of controlled vocabularies that can be used with DDI as well as for other purposes and applications. Select DDI Alliance vocabularies are already in use at organizations like the Finnish Social Science Data Archive (FSD), the GESIS - Leibniz Institute for the Social Sciences, the Inter-university Consortium for Political and Social Science (ICPSR), Mathematica Policy Research,  the UK Data Archive (UKDA), and the University at Bielefeld, Germany. Nesstar Publisher (http://www.nesstar.com/) now incorporates the controlled vocabularies for Analysis Unit and Time Method.

A paper on "Controlled Vocabularies for DDI 3: Enhancing Machine-Actionability" provides additional background on this effort.

 
Download
Download package with latest versions of all DDI Controlled Vocabularies: DDI-CV_2018-07-18.zip
 

The vocabularies are published in an XML format called Genericode, an OASIS specification. The Genericode format provides a tabular model for code lists. They are also made available in HTML and XLS (Excel) form.

Usage information for each controlled vocabulary is available in the vocabulary documentation. Usage instructions specific to DDI Lifecycle, as well as recommendations for citing the CVs outside DDI are also available, along with examples. The published DDI-CVs work with both versions of the DDI specification.

Please note that the production, publication, and maintenance of translations are currently outside CVG's scope, but CVG would appreciate being informed if other agencies are interested in, or planning to undertake such tasks. If translations are produced by other organizations, CVG can make them available for consultation, but will not assume responsibility for their content, or maintenance. Currently, the following translations are available for reference:

Name Title Languages File Type
AnalysisUnit Analysis Unit DEFI xls
TimeMethod Time Method DEFI xls

 

The CVG functions as the management team for the vocabularies. Comments, as well as suggestions for amendments or additions, are welcome from all users. To provide feedback, or submit proposals for changes, please contact the CVG. Please note that the production, publication, and maintenance of translations are currently outside CVG's scope, but CVG would appreciate being informed if other agencies are interested in, or planning to undertake such tasks.

The DDI CV versioning policy as described below has been approved by the DDI Alliance in November 2012 and is published and implemented starting February 2013. This new protocol supersedes the previous policy which was based on a three-digit version numbering system. Users who have referenced these vocabularies prior to February 1, 2013 will need to retroactively change any reference to V. 1.0.0 into V. 1.0. From that point on, new versions can be used and referenced normally.

The controlled vocabularies versioning policy is based on an intellectual, or logical, assessment of the nature of change, which distinguishes between substantive and non-substantive changes in the CVs, as described further below. To reflect this distinction, the version numbering system is based on a two-level structure (examples: 1.0, 1.1, 1.2, 2.0, etc.). A change in the integral part of the decimal number will indicate a substantive change in the controlled vocabulary. A substantive change is any change in the list's short name, long name (title), content, or meaning as well as in a code's value or meaning. A change in the fractional part of the version number will indicate a non-substantive change. Non-substantive changes are changes in wording, spelling, etc. (i.e., "form") that do not involve changes in intellectual content or meaning. All version levels (i.e., the full decimal number, even when the fractional part is zero) will always be mentioned.

Versioning of the CVs is done at the level of each published controlled vocabulary, and not at the item level.

An item in a CV list consists of the following parts:

Code The specific content that is entered into the DDI specification to identify the item. In hierarchical lists, all of the levels are always mentioned in each code, and are separated by a period.
Term The display label associated with the code. This may be available in multiple languages.
Definition The definition of the code. This may be available in multiple languages.

 

The following table lists the controlled terms or phrases used to document CV changes, provides the logical expression as well as a natural language description for each type of change, and indicates whether a change is substantive or non-substantive.

Documentation term/phrase Logical expression Explanation Substantive (SC)/non-substantive (NSC) type of change
CV LONG NAME CHANGED X → Z The long name (title) of the vocabulary is changed. SC
CV SHORT NAME CHANGED X → Z The short name of the vocabulary is changed. SC
CV DEFINITION AMENDED WITH MEANING CHANGE X The CV definition is amended to reflect a change in meaning for the CV. SC
CODE REMOVED X → Code X is deleted from the CV. SC
CODE ADDED → Z A new code Z is added to the CV. SC
CODE TAKEOVER X, Y, (n) → Y One or more codes (X, n) are deleted, and their meaning is taken over by the existing code Y. SC
CODE MERGER X, Y, (n) → Z Two or more codes (X, Y, n) are deleted, and their meaning is taken over by a new code Z. SC
CODE SPLIT-OFF X → X, Z, (n) The meaning of code X is narrowed and one or more new codes (Z, n) are added to cover the remainder of the meaning previously held by code X alone. SC
CODE BREAKDOWN X → Za, Zb (n) Code X is deleted, and its meaning is distributed among two or more new codes Za, Zb, n. SC
CODE TRANSFER X, Y, (n) → X, Y, (n) The meaning of code X is narrowed and the remainder of the meaning is transferred to one or more existing codes (Y, n). SC
CODE VALUE CHANGED X → Z The value of code X is changed to Z but its definition remains the same. SC
CODE DEFINITION AMENDED WITH MEANING CHANGE X The definition for code X is amended to reflect a change in meaning for code X. SC
CODE DEFINITION REPHRASED WITH NO MEANING CHANGE X The definition for code X is rephrased for clarity, edited for accuracy, or an example is added or deleted without a change in meaning. NSC
DESCRIPTIVE TERM REPHRASED WITH NO MEANING CHANGE X The term describing code X is rephrased for clarity or edited for accuracy, without a change in meaning. NSC
CV DEFINITION REPHRASED WITH NO MEANING CHANGE X The definition for the CV is rephrased for clarity, edited for accuracy. NSC

In addition to a change in the version number, each new version of a CV will contain documentation about how the new CV compares with the previous version. In the Genericode XML, the changes will be documented using the following structure:

CV LONG NAME CHANGED:
Kind Of Data Format changed to General Data Format
CV SHORT NAME CHANGED:
KindOfDataFormat changed to GeneralDataFormat
CV DEFINITION AMENDED:
AnalysisUnit
CODE REMOVED:
SelfAdministeredQuestionnaire.FixedForm
SelfAdministeredQuestionnaire.Interactive
CODE ADDED:
Other
CODE TAKEOVER:
Interview.FaceToFace.CAPI taken over by Interview.FaceToFace.CAPICAMI
CODE MERGER:
Interview.FaceToFace.CAPI and Interview.FaceToFace.CAMI merged into Interview.FaceToFace.CAPICAMI.
CODE SPLIT OFF:
Interview.FaceToFace.CAPICAMI narrowed. Remainder of the meaning split between Interview.FaceToFace.CAPI and Interview.FaceToFace.CAMI.
CODE BREAKDOWN:
Interview.FaceToFace.CAPICAMI removed. Meaning distributed between Interview.FaceToFace.CAPI and Interview.FaceToFace.CAMI
CODE TRANSFER:
Interview.FaceToFace.CAPICAMI narrowed. Remainder of the meaning transferred to Interview.FaceToFace.CAMI.
CODE VALUE CHANGED:
Interview.FaceToFace.CAPICAMI changed to Interview.FaceToFace.CAPIorCAMI
CODE DEFINITION AMENDED:
Longitudinal.Panel
CODE DEFINITION REPHRASED:
Interview
SelfAdministeredQuestionnaire.CAWI
DESCRIPTIVE TERM REPHRASED:
Interview: Face-to-face: CAOI rephrased into Interview: Face-to-face: CAPI
CV DEFINITION REPHRASED:
AnalysisUnit

 

Note: DDI-CVG has also produced a set of guidelines to support controlled vocabularies users in retrofitting their collections following the publication of new CV versions. Please note that these are only intended as recommendations, and are not being enforced as part of the versioning policy.

The table below lists the latest versions of the CVs currently available and provides download links for each format.

See all versions

Name Title Description File Type Version
  • html: rendering as web page
  • xml: Genericode (version 1.0, DDI-CV profile 1.0)
  • xls: Excel (version 2003)
AggregationMethod Aggregation Method

Identifies the type of aggregation used to combine related categories, usually within a common branch of a hierarchy, to provide information at a broader level than the level at which detailed observations are taken. (From: The OECD Glossary of Statistical Terms)

html, xml, xls V 1.0
AnalysisUnit Analysis Unit

Describes the entity being analyzed in the study or in the variable.

html, xml, xls V 1.0
CharacterSet Character Set

Standard set of characters upon which many character encodings are based (Wikipedia).

html, xml, xls V 1.0
CommonalityType Commonality Type

Describes the degree of similarity between two items or schemes (collections of items).

html, xml, xls V 1.0
DataSourceType Data Source Type

Includes a typology of data sources.

html, xml, xls V 1.0
DataType Data Type

Identifies the type of data, which has a bearing on the acceptable data values, the operations that can be performed with the data, and the ways in which the data are stored. The present list is based on the W3C data types, and includes the terms relevant for documenting research data.

html, xml, xls V 1.0
DateType Date Type

Specifies the type of date. The present list is based on ISO 8601 usage.

html, xml, xls V 1.1

GeneralDataFormat

(formerly KindOfDataFormat)

General Data Format Describes the physical format(s) of the data documented in the logical product(s) of a study unit. htmlxmlxls V 2.0
LanguageProficiency Language Proficiency

Describes the level of proficiency of an individual in a natural language.

html, xml, xls V 1.0
LifecycleEventType Lifecycle Event Type

Specifies the event happening over the data life cycle that is considered significant enough to document.

html, xml, xls V 1.0
ModeOfCollection Mode of Collection

The procedure, technique, or mode of inquiry used to attain the data.

html, xml, xls V 3.0
NumericType Numeric Type

Specifies the type of numeric data.

html, xml, xls V 1.0
ResponseUnit Response Unit

Indicates the entity that provided the information carried by the variable.

html, xml, xls V 1.0
SamplingProcedure Sampling Procedure

Includes a typology of sampling methods.

html, xml, xls V 1.1
SoftwarePackage Software Package

Indicates the statistical software package used in the production/processing/dissemination of the data. Data collection software is not covered in this list.

html, xml, xls V 1.0
SummaryStatisticType Summary Statistic Type

Specifies the type of summary statistic. Summary statistics are a single number representation of the characteristics of a set of values.

html, xml, xls V 2.1
TimeMethod Time Method

Describes the time dimension of the data collection.

html, xml, xls V 1.2
TimeZone Time Zone

Time zone specification as an offset from UTC (Coordinated Universal Time) in terms of hours and minutes.

html, xml, xls V 1.0
TypeOfAddress Type of Address

Identifies the type of address entered as contact information for an individual or an organization.

html, xml, xls V 1.0
TypeOfConceptGroup Type of Concept Group

Specifies the rationale for creating a concept group.

html, xml, xls V 1.0
TypeOfInstrument Type of Instrument

Includes a typology of data collection instruments.

html, xml, xls V 1.1
TypeOfNote Type of Note

Includes a typology of notes.

html, xml, xls V 1.0
TypeOfTelephone Type of Telephone

Identifies the type of telephone entered as contact information for an individual or an organization.

html, xml, xls V 1.0

See all versions