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United States National Library of Medicine National Institutes of Health

Leasing Data from the National Library of Medicine®

NLM® currently leases:

  1. Journal citations (MEDLINE® and OLDMEDLINE)
  2. Records for Books, Serials, Audiovisuals, and Other Resources - includes Catfile, CatfilePlus, and Serfile
  3. Data distributed from TOXNET® - includes CCRIS, ChemIDplus, DIRLINE®, GENE-TOX, HSDB®, and TOXLINE® Special
  4. Unified Medical Language System® (UMLS®) Knowledge Sources - includes the UMLS Metathesaurus®, Semantic Network, and SPECIALIST Lexicon

There is no charge for leasing NLM data or licensing the UMLS from NLM.

The MeSH® Vocabulary may be downloaded at no cost after completion of a brief Memorandum of Understanding.

NLM does not provide search software.

Those interested in obtaining NLM data (described in items 1-3 above) directly from an NLM licensee do not enter into a license agreement with the NLM. Rather, contact the licensee directly.

UMLS licensees are prohibited from distributing the UMLS products or subsets of these products, including individual vocabulary sources within the Metathesaurus, except as an integral part of computer applications developed by the licensee for a purpose other than redistribution of data contained in the UMLS products. UMLS licensees agree to inform NLM prior to distributing any application(s) that use the UMLS products.

Linking to NLM Web Sites
MEDLINE and other databases are searchable at no cost from NLM's Web site at http://www.nlm.nih.gov. Organizations with Web sites may provide access to NLM data for their customers by creating Web links from their site to NLM services such as PubMed®, LocatorPlus, and MEDLINEplus®. See Linking to PubMed and other Entrez databases, Linking to MEDLINEplus, and Information on Copyright for additional information. Contact custserv@nlm.nih.gov for more information about this option.

For More Information
For more information about leasing NLM data (other than the UMLS Metathesaurus), or to obtain samples of NLM's MARC 21-formatted products, contact Jane Rosov, MEDLARS Management Section, National Library of Medicine, 8600 Rockville Pike, Bethesda, Maryland 20894, or e-mail janer@nlm.nih.gov.

For more information about leasing the UMLS Metathesaurus, e-mail umls_support@nlm.nih.gov.


Journal Citations (MEDLINE and OLDMEDLINE)

Content
MEDLINE, the primary component of PubMed®, is the NLM's premier bibliographic database containing references to journal articles covering basic biomedical research and the clinical sciences including: nursing, dentistry, veterinary medicine, pharmacy, allied health, and pre-clinical sciences. There is now increased coverage of life sciences and the fields of history of medicine, health technology assessment, space, and bioethics. The database contains bibliographic citations and author abstracts from over 4,700 biomedical journals published in the United States and 70 other countries. It contains over 12 million records dating back to the mid-1960's, as well as some older records in certain subject areas primarily created by NLMs collaborating partners. Approximately 600,000 records are expected to be added in 2004. Coverage is worldwide, but most records are from English-language sources or have English abstracts. See the Fact Sheet "What's the Difference Between MEDLINE and PubMed?". NLM also exports to MEDLINE licensees other categories of records that reside in PubMed: a) the out-of-scope citations from a few selectively indexed MEDLINE journals (primarily covering general science and chemistry) for which the life sciences articles are indexed for MEDLINE; b) some citations in PubMed that precede the date a journal was selected for MEDLINE indexing; and c) some citations to articles in additional life science journals that submit full text to PubMedCentral™ and receive a qualitative review by NLM. NLM now exports over 98% of PubMed content to MEDLINE licensees.

OLDMEDLINE currently contains approximately 1,700,000 citations to articles from international biomedical journals covering the fields of medicine, preclinical sciences and allied health sciences from 1951 through 1965. NLM expects to continue converting citations from its older medical indexes to machine-readable form and to add these citations to OLDMEDLINE as time and resources permit. NLM expects to add 1950 data to OLDMEDLINE late 2004.

Specifications
NLM distributes MEDLINE in XML format. See MEDLINE Characters for information on use of diacritical marks and UTF-8 encoding. A new fully maintained MEDLINE baseline database containing approximately 12 million records is generated each December and is distributed on DLT tape or via ftp to new licensees. The current baseline database requires 46.6 GB disk space; 6.1 GB compressed. Updates to the baseline files containing new and revised records during the year are available via ftp and should be applied by licensees regularly. Licensees must reload a complete new baseline database each year. It is unlikely NLM will offer an alternative option of end-of-year changed records-only in the future. See Additional Information below.

OLDMEDLINE is also distributed in XML format entirely via ftp. Updates containing new records are irregular and infrequent. NLM expects to release revised records quarterly.

Sample NLM Data
Sample MEDLINE and OLDMEDLINE data are also available for prospective NLM data licensees. A license agreement is not needed for sample data. MEDLINE data element descriptions are also available. The current treatment of these elements for OLDMEDLINE is outlined in the announcement at http://www.nlm.nih.gov/bsd/license_announce/announce_03_sep_5.html

How to Lease
NLM leases MEDLINE and OLDMEDLINE to U.S. individuals or organizations; to its formally recognized International MEDLARS Centers; and to non U.S. individuals or organizations solely for research purposes (limited to internal use with no commercial citation search service offered). For purposes of leasing NLM databases, the following criteria must be met to be considered a U.S. organization: the organization is incorporated in U.S.; the signing official is a principal in the organization who is located in the U.S. and is not simply an authorized agent; and any financial payment to the NLM is issued from an U.S. account (although there are no fees for leasing NLM databases in the foreseeable future). Complete and return the following to Jane Rosov, MEDLARS Management Section, National Library of Medicine, 8600 Rockville Pike, Bethesda, Maryland 20894:

  1. Two copies of the applicable License Agreement
  2. Intended Use Worksheet.

License requests received after October 2004 will be processed for distribution of the 2005 version of MEDLINE/PubMed late December 2004.

Obtain NLM's usage report form at http://www.nlm.nih.gov/databases/license/userep.html for submission at the end of the U.S. Federal Government fiscal year, i.e., after September 30.

MEDLINE licensees must retain a minimal set of data elements.

Alternative to Leasing
MEDLINE and OLDMEDLINE may be downloaded for personal use and a single copy of downloaded data may be redistributed. Small amounts of MEDLINE and OLDMEDLINE data may be retrieved from PubMed for redistribution without entering into a formal licensing agreement. See Information on Copyright for additional details.

Additional Information
MEDLINE update files may contain new or revised versions of Completed, In-process, PubMed-not-MEDLINE, and In-Data-Review status records, and deleted records. Update files are generally available to licensees Tuesday-Saturday except for several weeks in November and December when only in-process records are distributed. Various types of maintenance take place during the year so licensees are urged to process revised records distributed in update files as well as new and deleted records regularly.

Announcements and documentation for licensees are posted at the Information for Licensees of NLM Data page found at http://www.nlm.nih.gov/bsd/licensee.html. Licensees are also encouraged to read the NLM Technical Bulletin and to subscribe to NLM's e-mail alert, NLM-Announces (see http://www.nlm.nih.gov/news/nlmfiles-email.html).

The MeSH Vocabulary, a companion database for MEDLINE , may be downloaded at no cost after completion of a brief Memorandum of Understanding.

Information about journals cited in MEDLINE and OLDMEDLINE, including the complete title of the journal, is found in:

  1. The List of Serials Indexed for Online Users available in PDF and XML format at http://www.nlm.nih.gov/tsd/serials/lsiou.html and the List of Journals Indexed in Index Medicus available at http://www.nlm.nih.gov/tsd/serials/lji.html (these publications do not cover OLDMEDLINE journal titles)
  2. LOCATORPlus, the NLM's online catalog at http://locatorplus.gov
  3. Serfile, another file that may be leased from NLM (see http://www.nlm.nih.gov/databases/leased.html)
  4. PubMed journals files located at http://www.nlm.nih.gov/bsd/Serfile_addedinfo.html (contains limited journal information; updated daily)
  5. Entrez Journals database at http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=journals for basic journal information similar to data found in PubMed journals list (available in the Entrez Utilities at http://www.ncbi.nlm.nih.gov/entrez/query/static/eutils_help.html; updated daily).


Records for Books, Serials, Audiovisuals, and Other Resources (Catfile, CatfilePlus, and Serfile)

NLM offers three bibliographic products derived from the MARC 21 data in LocatorPlus: Catfile, CatfilePlus, and Serfile.

Content and Specifications
NLM bibliographic records for serials, monographs, audiovisuals, computer software, electronic resources and other materials are available on a subscription basis.

Catfile is available in MARC 21 format only.

CatfilePlus and Serfile are available in MARC 21 format.

As of August 2004, CatfilePlus and Serfile are also available in XML format.

These XML products are referred to as "CatfilePlus in XML" and "Serfile in XML"

Sample NLM Data
Samples of Catfile (in MARC 21 format only) , CatfilePlus (in MARC 21 or XML format) and Serfile (in MARC 21 or XML format) are available for prospective NLM data licensees. A license agreement is not needed for sample data. Sample files of MARC 21-formatted products are available upon request. For instructions on how to obtain the sample files of XML products, refer to Sample NLM Data)

How to Lease
NLM leases Catfile, CatfilePlus and Serfile to U.S. and non-U.S. individuals or organizations. Complete and return the following to Jane Rosov, MEDLARS Management Section, National Library of Medicine, 8600 Rockville Pike, Bethesda, Maryland 20894:

  1. Two copies of the applicable License Agreement
  2. Intended Use Worksheet.

Alternative to Leasing
Individual records in MARC 21 format may be downloaded from LocatorPlus for personal use and a single copy of downloaded data may be redistributed. An alternative product, the List of Serials Indexed for Online Users (LSIOU), a subset of Serfile, is available in XML and PDF format. The LSIOU provides basic bibliographic information for only the serials from which articles are indexed with the MeSH® vocabulary and cited in MEDLINE (does not cover OLDMEDLINE titles). See http://www.nlm.nih.gov/tsd/serials/lsiou.html for more information. Please note that the LSIOU uses its own DTD which is different from the DTD used for SERFILE.

Additional information
Sample files and further documentation of the data elements included in Catfile, CatfilePlus, and Serfile are available to potential licensees upon request. General information on the MARC 21 record structure is available from the Library of Congress at http://lcweb.loc.gov/marc/marcdocz.html. Catfile, CatfilePlus, and Serfile may be leased to non-U.S. organizations.


Data distributed from TOXNET®

Content and Specifications
CCRIS, ChemIDplus, DIRLINE®, GENE-TOX, HSDB®, and TOXLINE® Special
Click on each database name above for a description of that database. All are available for distribution in XML format via ftp. See CCRIS, DIRLINE®, GENE-TOX, HSDB®, and TOXLINE® Special Available to Licensees in XML Format via FTP [12 March 2002; revised - 23 April 2002] and ChemIDplus Available For Distribution [16 April 2002] for additional information.

Special note for ChemIDplus: Restrictions apply to data with the source tag of USPDDN. The U.S. Pharmacopeia Convention, Inc. (USP), the provider of USPDDN data for ChemIDplus, requires special arrangements with NLM's licensees before NLM may distribute the database. All ChemIDplus licensees should contact Christine Colburn at USP (cwc@usp.org). Any exceptions to the restrictions will be made by USP. You should inform NLM that your arrangements have been made when the license paperwork is first submitted and when a new Intended Use Worksheet is submitted each subsequent year. Currently, ChemIDplus structures are not available for distribution to licensees.

Special note for TOXLINE Special: Restrictions apply to the BIOSIS and IPA archival subfiles. BIOSIS and the American Society of Health-System Pharmacists (ASHP), the producer of IPA, require special arrangements with NLM's licensees before NLM may distribute BIOSIS or IPA data. TOXLINE Special licensees who wish to obtain these subfiles from NLM should contact Tim Lawler at BIOSIS (tlawler@biosis.org or 215-231-7471) and Carol Wolfe at ASHP (301-657-3000 x 1569). Any exceptions to the restrictions will be made by the data suppliers. If you wish to receive BIOSIS or IPA data, you should inform NLM that your arrangements have been made when the license paperwork is first submitted and when a new Intended Use Worksheet is submitted each subsequent year. Please note that NLM is not currently adding BIOSIS or IPA data to TOXLINE Special.

Sample NLM Data
Sample data is available for prospective NLM data licensees. A license agreement is not needed for sample data.

How to Lease
NLM leases CCRIS, ChemIDplus, DIRLINE®, GENE-TOX, HSDB® and TOXLINE® Special to U.S. individuals or organizations; to its formally recognized International MEDLARS Centers; and to non-U.S. individuals or organizations solely for research purposes (limited to internal use with no commercial applications). For purposes of leasing NLM databases, the following criteria must be met to be considered a U.S. organization: the organization is incorporated in the U.S.; the signing official is a principal in the organization who is located in the U.S. and is not simply an authorized agent; and any financial payment to the NLM is issued from an U.S. account (although there are no fees for leasing NLM databases in the foreseeable future). Complete and return the following to Jane Rosov, MEDLARS Management Section, National Library of Medicine, 8600 Rockville Pike, Bethesda, Maryland 20894:

  1. Two National Library of Medicine License Agreements to Lease NLM Databases in Machine-Readable Form,
  2. Intended Use Worksheet (includes WWW sheet).

Obtain NLM's usage report form at http://www.nlm.nih.gov/databases/license/userep.html for submission at the end of the U.S. Federal Government fiscal year, i.e., after September 30.

Alternative to Leasing
CCRIS, GENE-TOX, HSDB, ChemIDplus, and TOXLINE Special records may be downloaded from the Toxicology Data Network (TOXNET). DIRLINE records may be downloaded from DIRLINE: Directory of Health Organizations.


Unified Medical Language System (UMLS)

Content
The purpose of the UMLS is to aid the development of systems that help health professionals and researchers retrieve and integrate electronic biomedical information from a variety of sources and to make it easy for users to link disparate information systems, including computer-based patient records, bibliographic databases, factual databases, and expert systems. The UMLS project develops "Knowledge Sources" that can be used by a wide variety of applications programs to overcome retrieval problems caused by differences in terminology and the scattering of relevant information across many databases.

There are three UMLS Knowledge Sources:

The Metathesaurus provides a uniform, integrated distribution format from over 100 biomedical vocabularies and classifications, and links many different names for the same concepts. The Lexicon contains syntactic information for many terms, component words, and English words, including verbs, including some that do not appear in the Metathesaurus. The Semantic Network contains information about the types or categories (e.g., "Disease or Syndrome," "Virus") to which all Metathesaurus concepts have been assigned and the permissible relationships among these types (e.g., "Virus" causes "Disease or Syndrome"). NLM also distributes associated lexical programs and software (MetamorphoSys) helpful in producing customized versions of the UMLS Metathesaurus.

Specifications
All the Knowledge Sources are available to licensed UMLS users via the Internet from the UMLS Knowledge Source Server which has a Web interface and an applications program interface (API). ASCII relational files downloadable by ftp are available from the Server and may also be requested on CD-ROM.

How to Lease
Complete and return the UMLS license agreement via surface mail to Sheldon Kotzin, Chief, Bibliographic Services Division, National Library of Medicine, 8600 Rockville Pike, Bethesda, Maryland 20894 or fax the agreement to Mr. Kotzin at 301-496-0822. UMLS licensees may have to establish separate license agreements with the producers of some specific vocabularies included in the Metathesaurus. Some of the material in the UMLS Metathesaurus is from copyrighted sources. For more information on use and restrictions, see: http://www.nlm.nih.gov/research/umls/license.html.

Within 30 days of the end of any calendar year in which the UMLS licensee makes use of the UMLS Metathesaurus, the licensee agrees to provide NLM with a brief report on the usefulness of the UMLS Metathesaurus in general and, if applicable, on the usefulness of the American Medical Association's CPT-Current Procedural Terminology® in the UMLS format in particular.

Alternative to Licensing
None.

Additional Information
A complete description of the Knowledge Sources and their distribution formats can be found in the UMLS Documentation.


Return to Information for Licensees of NLM Data

Last updated: 04 November 2004
First published: 01 January 1999
Metadata| Permanence level: Permanence Not Guaranteed