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Statistical Reports On MEDLINE®/PubMed® Baseline Data

Statistical Reports On MEDLINE®/PubMed® Baseline Data. NLM Technical Bulletin. 2004 Sep–Oct;(340):e1.

October 22, 2004 [posted]

NLM is pleased to provide a series of statistical reports run on 2002, 2003, and 2004 baseline MEDLINE/PubMed data with the expectation that researchers mining NLM data, and others, will find them useful.

The statistics are based upon the data elements in MEDLINE and include: total citations containing each element; total occurrences of each element; minimum/average/maximum occurrences of each element in a record; and minimum/average/maximum length of a single element occurrence; and other items. A full description of the content and formats of the reports and access to the data is available from http://www.nlm.nih.gov/bsd/licensee/med_baseline_statistics.html. NLM expects to make similar reports available after the conclusion of each production year.

The baseline database includes all MEDLINE records as well as the quality-assured non-MEDLINE records in PubMed. The PubMed display of the latter group of records contains the status tag [PubMed] next to the PMID (see PubMed Citation Status Subsets in PubMed Help), and the XML version contains the value PubMed-not-MEDLINE in the Status attribute of the MedlineCitation element (see http://www.nlm.nih.gov/bsd/licensee/data_elements_doc.html#medlinecitation).

The statistical reports were compiled by the Lister Hill Center of the Library, are freely available for use, and may be reproduced with attribution to the U.S. National Library of Medicine, Department of Health and Human Services using this citation:
Statistical reports on MEDLINE®/PubMed® baseline data [Internet]. Bethesda (MD): National Library of Medicine (US), Bibliographic Services Division; 2004 Sep 30 [updated 2004 Oct 1]. [about 3 screens]. Available from: [this link was removed because it is no longer valid].