Belmont Abbey College Library: Library Research: Controlled Vocabularies

What is a controlled vocabulary?

"A controlled vocabulary is an organized arrangement of words and phrases used to index content and/or to retrieve content through browsing or searching." (Patricia Harpring)

Controlled vocabularies...

define words and ideas
organize information
show relationships between words and ideas
show which words are preferred
improve search results

Why should I use controlled vocabularies?

Controlled vocabularies improve search results during your research process by using industry- or discipline-preferred terms.

Word choice is one of the most important steps during research. Controlled vocabularies can help you find the best words and phrases to use. They tell you how scholars and professionals in your field describe and define terms and ideas. By using more precise words, you will find that your results will be more relevant and useful.

For example, to find books of recipes, would you use "cookbooks" or "cookery"? For research on education, is "child rearing" or "child raising" the preferred phrase? What about "on-line" or "online"? "Automobile" or "car"? "Flower arranging" or "floristry"?

What are some examples of controlled vocabularies?

Controlled vocabularies can be broken down into different categories, depending on what kind of information they describe, and how they describe it. Some examples are:

alphanumeric classification (like library call numbers), which tell you where a book/other library material is shelved
subject headings (like Medical Subject Headings), which tell you the most precise terms to use
taxonomy (like Linnaean taxonomy), which show hierarchies
thesaurus (like the UNESCO Thesaurus), which show hierarchies, relationships, and the most precise terms to use
metadata standard (like Dublin Core), which show structures and relationships about data

Controlled Subject Headings

Library of Congress Subject Headings
Look up a topic to see what subject headings the Library of Congress uses to classify this subject. Use of controlled vocabularies yields tailored search results.
MeSH - Medical Subject Headings
Lookup a topic to see what subject headings the National Institute of Health uses to classify this subject. Use of controlled vocabularies yields tailored search results.
NAICS Codes
The North American Industry Classification System (NAICS) is the standard used by Federal statistical agencies in classifying business establishments for the purpose of collecting, analyzing, and publishing statistical data related to the U.S. business economy.
DublinCore
The Dublin Core Metadata Element Set is a vocabulary of fifteen properties for use in resource description. The name "Dublin" is due to its origin at a 1995 invitational workshop in Dublin, Ohio; "core" because its elements are broad and generic, usable for describing a wide range of resources.
NAICs Codes
North American Industry Classification System codes classify organizations by industry. - Proquest ABI/Inform

Using Controlled Vocabularies

Option 1) Library catalog

Use the Library of Congress subject headings to determine the best choice for your search terms. Once you have the right word(s), go to our Alexandria catalog. Set the search field to "full subject," and enter your word(s) exactly as it appeared in the Library of Congress website.

Image: Alexandria Catalog, subject heading search for "Civilization, Western"

Option 2) Databases - Search in Advanced search/Thesaurus

Many databases have an accessible controlled vocabulary, usually called a thesaurus and linked to in the advanced search function. Users can browse the thesaurus, and find preferred, broader, and narrower terms to refine their searches.

Image: ProQuest Central, Advanced Search screen that highlights the Thesaurus and the Subject search field

Option 3) Databases - Browse articles

Another convenient way to use controlled vocabularies is to look at the information about an article in a database. For example, in most ProQuest databases, each article will have a full text tab, and an abstract/details tab. Users can find subject headings under abstract/details. In the example below, the subejct headings are Nonfiction, Folklore, Mythology, and Source studies.

Image: ProQuest Research Library, abstract/details tab of a scholarly article

Related Resources

American Society for Indexing: Taxonomies & Controlled Vocabularies Special Interest Group
The Taxonomies & Controlled Vocabularies Special Interest Group (SIG) is a networking and educational forum for those in the indexing profession who are involved in creating or editing taxonomies, thesauri, or controlled vocabularies used for indexing. The Taxonomies & Controlled Vocabularies SIG is an affiliate of the American Society for Indexing.
Crowd Sourced Indexing
CSI: Crowd Sourced Indexing is a program created by Banai Lynn Feldstein in response to the lack of indexing programs in genealogy.
Getty: Introduction to Controlled Vocabularies (powerpoint)
This powerpointt is a companion presentation to the book, Introduction to Controlled Vocabularies, revised edition, 2013.
International Organization for Standardization
ISO is an independent, non-governmental international organization with a membership of 163 national standards bodies. Through its members, it brings together experts to share knowledge and develop voluntary, consensus-based, market relevant International Standards that support innovation and provide solutions to global challenges.
National Information Standards Organization
NISO is where content publishers, libraries, and software developers turn for information industry standards that allow them to work together. Through NISO, all of these communities are able to collaborate on mutually accepted standards — solutions that enhance their operations today and form a foundation for the future.
Taxonomy Warehouse
This free online information resource is all about taxonomy: Content and links to everything you need to know about taxonomy in one convenient website. Explore our subject-oriented directory of taxonomies and their publishers; peruse blogs and events about taxonomies; discover taxonomy books and standards; research taxonomy software products; and connect with experts and consulting services.

Science & Medicine

International Code of Nomenclature for algae, fungi, and plants (Melbourne Code)
Biology requires a precise and simple system of nomenclature that is used in all countries, dealing on the one hand with the terms that denote the ranks of taxonomic groups or units, and on the other hand with the scientific names that are applied to the individual taxonomic groups. The purpose of giving a name to a taxonomic group is not to indicate its characters or history, but to supply a means of referring to it and to indicate its taxonomic rank. This Code aims at the provision of a stable method of naming taxonomic groups, avoiding and rejecting the use of names that may cause error or ambiguity or throw science into confusion. Next in importance is the avoidance of the useless creation of names.
International Commission on Zoological Nomenclature
The International Code of Zoological Nomenclature is the system of rules and recommendations originally adopted by the International Congresses of Zoology and, since 1973, by the International Union of Biological Sciences (IUBS). The objects of the Code are to promote stability and universality in the scientific names of animals and to ensure that the name of each taxon is unique and distinct. All its provisions and recommendations are subservient to those ends and none restricts the freedom of taxonomic thought or actions.
International Committee on Taxonomy of Viruses (ICTV)
The advent of nucleotide sequence determination has revolutionized biology and largely rationalized taxonomy, including that of viruses. The universal virus taxonomy provides a classification scheme that is supported by verifiable data and expert consensus. It is an indispensable framework both for further study of the currently recognized virus species and for the identification and characterization of newly emergent viruses, whether they result from natural, accidental, or deliberate dissemination.
Linnaean Taxonomy
In the 18th century, Carl Linnaeus published a system for classifying living things, which has been developed into the modern classification system. People have always given names to things that they see, including plants and animals, but Linnaeus was the first scientist to develop a hierarchal naming structure that conveyed information both about what the species was (its name) and also its closest relatives. The ability of the Linnean system to convey complex relationships to scientists throughout the world is why it has been so widely adopted.
NASA Thesaurus
The NASA Thesaurus contains the authorized NASA subject terms used to index and retrieve materials in the NASA Technical Reports Server (NTRS) and the NTRS Registered (Formerly NA&SD). The scope of this controlled vocabulary includes not only aerospace engineering, but all supporting areas of engineering and physics, the natural space sciences (astronomy, astrophysics, planetary science), Earth sciences, and the biological sciences. The NASA Thesaurus contains over 18,400 subject terms, 4,300 definitions, and more than 4,500 USE cross references.
Thesaurus of Psychological Index Terms
APA's Thesaurus of Psychological Index Terms® helps researchers search the APA databases with maximum precision.
U.S. Department of Agriculture: National Agricultural Library: Thesaurus and Glossary
The Thesaurus and Glossary are online vocabulary tools of agricultural terms in English and Spanish and are cooperatively produced by the National Agricultural Library, USDA, and the Inter-American Institute for Cooperation on Agriculture as well as other Latin American agricultural institutions belonging to the Agriculture Information and Documentation Service of the Americas (SIDALC).
U.S. National Center for Biotechnology Information: Taxonomy
The Taxonomy Database is a curated classification and nomenclature for all of the organisms in the public sequence databases. This currently represents about 10% of the described species of life on the planet.
U.S. National Library of Medicine: Medical Subject Headings (MeSH)
Our main purpose is to provide a hierarchically-organized terminology for indexing and cataloging of biomedical information such as MEDLINE/PUBmed and other NLM databases. We also distribute pharmaceutical information through our RxNorm database, and manage the curation of the UMLS and SnoMed database.
Unified Astronomy Thesaurus
The Unified Astronomy Thesaurus (UAT) is an open, interoperable and community-supported thesaurus which unifies the existing divergent and isolated Astronomy & Astrophysics thesauri into a single high-quality, freely-available open thesaurus formalizing astronomical concepts and their inter-relationships. The UAT builds upon the existing IAU Thesaurus with major contributions from the Astronomy portions of the thesauri developed by the Institute of Physics Publishing and the American Institute of Physics.

Art & Special Collections

Ethnographic Thesaurus (AFSET)
The AFS Ethnographic Thesaurus (version 2.2) is a vocabulary that can be used to improve access to information about folklore, ethnomusicology, ethnology, and related fields.
Getty Research Institute: Art & Architecture Thesaurus (AAT)
AAT is a structured vocabulary, including terms, descriptions, and other metadata for generic concepts related to art, architecture, conservation, archaeology, and other cultural heritage. Included are work types, styles, materials, techniques, and others.
Getty Research Institute: Cultural Objects Name Authority (CONA)
CONA compiles titles, attributions, depicted subjects, and other metadata about works of art, architecture, and other cultural heritage, both extant and historical, linked to museum collections, special collections, archives, libraries, scholarly research, and other resources. CONA is linked to the AAT, TGN, ULAN, and the Getty
Getty Research Institute: Thesaurus for Graphic Materials (TGM)
The Thesaurus for Graphic Materials (TGM) is a tool for indexing visual materials by subject and genre/format. The thesaurus includes more than 7,000 subject terms to index topics shown or reflected in pictures, and 650 genre/format terms to index types of photographs, prints, design drawings, ephemera and other categories. New terms are added regularly.
Getty Research Institute: Thesaurus of Geographic Names (TGN)
TGN is a structured vocabulary, including names, descriptions, and other metadata for extant and historical cities, empires, archaeological sites, and physical features important to research of art and architecture. TGN may be linked to GIS, maps, and other geographic resources.
Getty Research Institute: Union List of Artist Names (ULAN)
ULAN is a structured vocabulary, including names, biographies, related people, and other metadata about artists, architects, firms, studios, museums, patrons, sitters, and other people and groups involved in the creation and study of art and architecture.
Iconclass
Iconclass is a classification system designed for art and iconography. It is the most widely accepted scientific tool for the description and retrieval of subjects represented in images (works of art, book illustrations, reproductions, photographs, etc.) and is used by museums and art institutions around the world.
RBMS Controlled Vocabularies
Welcome to the Controlled Vocabularies for Use in Rare Book and Special Collections Cataloging, developed and maintained by the Bibliographic Standards Committee of the Rare Books and Manuscripts Section (ACRL/ALA). These thesauri provide standardized vocabulary for retrieving special collections materials by form, genre, or by various physical characteristics that are typically of interest to researchers and special collections librarians, and for relating materials to individuals or corporate bodies.

Libraries

Dewey Decimal Classification System
The Dewey Decimal Classification (DDC) system is a general knowledge organization tool usually used to organize library materials.
Library of Congress Authority Name Files
Using Library of Congress Authorities, you can browse and view authority headings for Subject, Name, Title and Name/Title combinations; and download authority records in MARC format for use in a local library system.
Library of Congress Classification System
The LCC Classification system is an organizational tool usually used to organize library materials.
Library of Congress Subject Headings
Library of Congress Subject Headings (LCSH) has been actively maintained since 1898 to catalog materials held at the Library of Congress. By virtue of cooperative cataloging other libraries around the United States also use LCSH to provide subject access to their collections. In addition LCSH is used internationally, often in translation. LCSH in this service includes all Library of Congress Subject Headings, free-floating subdivisions (topical and form), Genre/Form headings, Children's (AC) headings, and validation strings* for which authority records have been created.
Ranganathan Colon Classification
Colon Classification, system of library organization developed by the Indian librarian S.R. Ranganathan in 1933. It is general rather than specific in nature, and it can create complex or new categories through the use of facets, or colons. The category of dental surgery, for example, symbolized as L 214:4:7, is created by combining the letter L for medicine, the number 214 for teeth, the number 4 for diseases, and the number 7 for surgery. - Encyclopedia Britannica
Library of Congress Genre/Form Terms for Library and Archival Materials (LCGFT)
Library of Congress Genre/Form Terms for Library and Archival Materials (LCGFT) provides over 600 terms that describe what something is instead of what it is about. As of late 2014 it includes terms in the disciplines of moving images (films and television programs), sound recordings, cartography, and law. Projects to add terms for literature, music, religion, and “general” terms (e.g., dictionaries, encyclopedias) are underway.

Journalism & Politics

International Press Telecommunications Council
Open standards for the news media.
UNESCO Thesaurus
The UNESCO Thesaurus is a controlled and structured list of terms used in subject analysis and retrieval of documents and publications in the fields of education, culture, natural sciences, social and human sciences, communication and information. Continuously enriched and updated, its multidisciplinary terminology reflects the evolution of UNESCO's programmes and activities.