Classification & indexing in health libraries

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Introduction

See also Medical Subject Headings (MeSH) and National Library of Medicine (NLM) Classification Scheme

Medical libraries around the world have used the National Library of Medicine classification scheme to organize their collections since it was first developed in the 1940s. Its development as a faceted scheme can be traced back to the work of medical bibliographer John Shaw Billings in the 1880s, Herbert Putnam and Cutter's work on the Library of Congress classification system in the late 1890s as well as Belgians Paul Otlet and Henri de Lafontaine's work on the Universal Decimal Classification system during the same period. The NLM Classification Ws - Medicine & related subjects, a vacant part of the Library of Congress scheme since it was first developed in 1897, is a more detailed classification system than just about any other currently used in health libraries. Several American health librarians such as Mary L. Marshall and Frank B. Rogers developed the NLM scheme in the 1940s and 1950s. The LOC and NLM systems are designed to work together to ensure optimal resource discovery (or findability), browsing and seamless access to pre-clinical and clinical materials in health libraries. (See also Melvil Dewey).

"Barnard" classification of books

The "Barnard" classification of books was introduced in the United Kingdom in 1936 by Cyril Cuthbert Barnard (1894-1959) who was the librarian at the London School of Hygiene and Tropical Medicine. The Barnard classification is still used to this day in some British and European tropical medicine and veterinary medicine libraries.

NLM & LOC plus MeSH

The NLM classification scheme, with the NLM Medical Subject Headings (MeSH) thesaurus, is a means to organize and describe materials held in health libraries. These major tools help health librarians and their users move seamlessly from biomedical databases (i.e. journal collections) to library catalogues (i.e. print/digital items) and to locate information. Several international classification systems permit the assignment of alpha-numeric (or numeric alone) call numbers to bring out medical facets in various intellectual works, notably the Dewey Decimal Classification and the Library of Congress Classification. Indexing of articles or subject analysis in biomedicine is generally accomplished using the NLM's medical subject headings (MeSH) thesaurus. However, the LC Subject Headings have been used by some health libraries to describe monographs, audiovisual materials and realia of various kinds. A number of controlled vocabularies are used in nursing (CINAHL headings) and pharmacy (EMTREE headings).

Canadian context

Most academic health and hospital libraries in Canada make simultaneous use of the NLM and Library of Congress systems. Consequently, the QS-QZs and Ws (NLM) are used in conjunction the pre-clinical Q-QRs (LOC) categories. Some Canadian consumer health and patient libraries use the Planetree classification system as it reflects the level of specificity needed to classify those collections. (See InspireHealth Vancouver catalogue). Some Canadian health libraries such as the Canada Institute for Scientific and Technical Information (CISTI) and the University of Alberta Health Libraries have opted to use LOC instead of the NLM system. The difference is that the LOC system places medicine in the Rs. In a recent study, it was revealed that 75% of academic health sciences libraries use the NLM classification system and 95% use MeSH (Medical Subject Headings). General libraries at the same institutions overwhelmingly use the systems developed by the Library of Congress. The most compelling reason for the use of NLM systems is that they are considered the most appropriate for medical collections and facilitate accurate access to and description of materials.

The impact of the web and digital content

With the rise of social tagging in web 2.0 and the semantic web, as well as other web trends such as Open Access, the question arises whether the NLM classification and subject analysis systems are flexible and robust enough to deal with changes in online access to biomedical information. There is considerable room for debate on this point. One important factor in this debate will undoubtedly be the release in 2010 of the third edition of AACR2 called Resource description and access (RDA) which attempts to account for linking to digital access and objects on the web from within health library catalogues. Some medical websites have used the Universal Decimal Classification (UDC) to organize browsable categories at their sites (see Intute) although the NLM system is generally viewed by health librarians as the better system.

References

• Coyle K, Hillmann D. Resource description and access: cataloging rules for the 20th Century. D-Lib Magazine. 2007;13(1/2):1082.
• Harper CA, Tillett BB. Library of congress controlled vocabularies and their application to the semantic web. Cataloging & Classification Quarterly. 2007;43(3-4).
• Joint Steering Committee (JSC) for development of RDA (Resource Description and Access). Collections Canada. Prospectus; 2008.
• Library of Congress Classification (LOC). Cataloging and Acquisitions; 2008
• Lyndenberg HM. John Shaw Billings: creator of the National Medical Library, and its catalogue. Chicago: American Library Association, 1924.
• MacCall SL. Online medical books: their availability and an assessment of how health sciences libraries provide access on their public websites. J Med Libr Assoc. 2006;94:75–80.
• NLM Classification tutorial, 2009
• Womack KR. Conformity for conformity's sake? The choice of a classification system and a subject heading system in academic health sciences libraries. Cataloging & Classification Q. 2006;42(1).
• Wikipedia. Dewey Decimal Classification.