MEDLINE

Database Description

Fields in This Database: Authors and Organizations · Titles · Medical Subjects · Subheadings · Other Subjects · Abstract · Issue Numbering · Codes

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Database Description: MEDLINE is the National Library of Medicine's (NLM) premier bibliographic database covering the fields of medicine, nursing, dentistry, veterinary medicine, the health care system, and the preclinical sciences. This database contains bibliographic citations (e.g., authors, title, and journal reference) and author abstracts from over 5,000 biomedical journals published in the United States and 70 foreign countries.

Journal articles are indexed for MEDLINE using NLM's controlled vocabulary, MeSH (Medical Subject Headings). Citations are created by the National Library of Medicine, International MEDLARS partners, and cooperating professional organizations.

MEDLINE provides comprehensive coverage for articles indexed 1966 to present. Historical citations (1950-1965) are included if they have been updated to current Medical Subject Headings.

MEDLINE has worldwide coverage, but 88% of the citations in current MEDLINE are to English-language sources and 76% have English abstracts. This database contains the citations that appear in the printed Index Medicus, as well as the citations of "special list" journals. Special list journals include those indexed for the Index to Dental Literature and the International Nursing Index. MEDLINE journal list.

In 2001, NLM reconfigured MEDLINE to contain only citations to journal articles (not books or book chapters), and to contain all journal article citations produced by NLM. MEDLINE now incorporates article citations that were previously part of separate databases, including AIDSLine, BioethicsLine, and HealthSTAR (Health Services Technology, Administration, and Research).

The National Library of Medicine's catalog of books, audiovisuals, and journal titles (not journal articles) is LOCATORPlus.

PRODUCED BY: National Library of Medicine.
DATES COVERED: 1966 to present, plus older citations (1950-1965) if updated to current Medical Subject Headings.
UPDATES: Daily.

Fields in This Database

AUTHORS AND ORGANIZATIONS

AUTHOR (.AU.): Prior to 2002, NLM supplied only initials of forenames. Starting with 2002 publications, NLM supplies the full author name, with spelled out forenames, if printed as the author of the article. Every author name in the database is now searchable in two formats:

Spelled out: forenames spelled out, or initials separated by a space	Initials: forename initials with no space
Sarhan, A R	Sarhan, AR
Yeh, S	Yeh, S
Lysaught, M T	Lysaught, MT
Lysaught, M Therese	Lysaught, MT
May, William E	May, WE
Rogers, Audrey Smith	Rogers, AS
Kincaid-Smith, Priscilla	Kincaid-Smith, P
de Prost, D	de Prost, D
Clavel, Jean-Pierre	Clavel, JP

To be sure to find all variant forms of a particular author name, you can use Browse by Author and select the variant forms. Example:

Copeland, L
Copeland, LA

Or, search surname and first initial followed by $:

(copeland l$).au.
finds COPELAND L and COPELAND L A

INSTITUTIONAL AFFILIATION (.IN.): Institutional affiliation of the first author.

CORPORATE NAME (.CO.): Starting with 2001, CO contains the name of a corporate or collective author of the work.

INVESTIGATOR (.INV.): NASA funded principal investigator(s) who conducted the research.

TITLES

TITLE (.TI.): Title of article. TI always contains an English-language title. For articles published in other languages, TI contains the title translated into English and enclosed in square brackets.

ORIGINAL TITLE (.OT.): Original title of article not published in English.

JOURNAL TITLE (.JN.): Name of journal, spelled out in full, in which the article was published.

JOURNAL ABBREVIATION (.JA.): The standard abbreviation for the journal title. This is the same abbreviation used in Index Medicus and other NLM publications and databases.

MEDICAL SUBJECTS

These fields contain terminology from the National Library of Medicine's controlled vocabulary, Medical Subject Headings, or MeSH. Subject headings, also called descriptors, describe the content of the article. NLM indexers assign as many MeSH headings as necessary (usually 10-12) to characterize the content and, in general, assign the most specific headings available.

MeSH is revised annually. See NLM's Medical Subject Headings Web site and Introduction to MeSH 2007. Libraries may also carry MeSH in print format.

Major subjects describe the most significant topics, or focus, of the article. In the record display, major subjects are preceded by an asterisk *. Minor subjects describe concepts which are also addressed in the article, but are not major concepts. In the record display, minor subjects are not asterisked. Subheadings, also called qualifiers, are terms that cover general, frequently discussed aspects of a subject, such as "diagnosis."

In the OhioLINK system, MeSH headings and subheadings are typically searched through the system's thesaurus functions. These functions allow users to look for a preferred heading; search, focus, or expand the heading; and select subheadings. Focus means retrieving only records in which the heading is a major concept. Expand means retrieving records with the heading plus all narrower headings.

However, if you know the exact MeSH heading and subheadings you're looking for, you can use the field qualifiers described here for quicker searching.

SUBJECTS (.SU.): SU encompasses both major and minor subject headings, or descriptors. This field contains main headings only, no subheadings. Using SU, you may search either complete subject phrases or individual subject keywords. For example:

pericarditis.su. finds:

Pericarditis
Pericarditis, Constrictive
Pericarditis, Tuberculous

SUBJECT THESAURUS (.SUT.): This field is defined primarily for system use when retrieving subjects through the thesaurus. SUT contains both the main heading and subheading, if applicable. Using SUT, you can search subject keywords or phrases in combination with a specific subheading (use the "with" operator).

SUBJECT THESAURUS, MAJOR (.MAJT.): This field is defined primarily for system use when retrieving subjects through "focus" in the thesaurus. MAJT contains both the main heading and subheading, if applicable. Using MAJT, you can search subject keywords or phrases in combination with a specific subheading (use the "with" operator).

SUBHEADINGS

Subheadings, also called qualifiers, are terms that cover general, frequently discussed aspects of a subject, such as "diagnosis." NLM indexers link subheadings with MeSH headings to describe exactly what aspects of the subject the author is discussing. Particular subheadings are defined for use with specific NLM subject categories.

SUBHEADING (.SH.): Each subheading, or qualifier, is identified by both a 2-letter code and a spelled-out phrase. For information about subheadings and the NLM subject classes to which they apply, see Introduction to MeSH 2007 and Qualifiers 2007.

Expert searchers sometimes search subheadings in combination with main headings that don't allow those subheadings, in order to retrieve articles that address desired aspects. For example:

acetaminophen.majt. and su.sh.

finds records that have Acetaminophen as a major heading, and su (surgery) as a subheading, although this main heading may not be linked to this particular subheading.

EXPLODED SUBHEADING (.XSH.): Some subheadings have hierarchical relationships. Exploded subheadings retrieve all the subheadings in a hierarchy. For example, adverse.xsh. finds Adverse Effects, Poisoning, and Toxicity.

Explode this subheading	Also finds
Adverse Effects	Poisoning, Toxicity
Analysis	Blood, Cerebrospinal Fluid, Isolation & Purification, Urine
Anatomy & Histology	Abnormalities, Blood Supply, Cytology, Embryology, Innervation, Pathology, Ultrastructure
Chemistry	Agonists, Analogs & Derivatives, Antagonists & Inhibitors, Chemical Synthesis
Complications	Secondary
Cytology	Pathology, Ultrastructure
Diagnosis	Pathology, Radiography, Radionuclide Imaging, Ultrasonography
Embryology	Abnormalities
Epidemiology	Ethnology, Mortality
Etiology	Chemically Induced, Complications, Congenital, Embryology, Genetics, Immunology, Microbiology, Parasitology, Secondary, Transmission, Virology
Metabolism	Biosynthesis, Blood, Cerebrospinal Fluid, Deficiency, Enzymology, Pharmacokinetics, Urine
Microbiology	Virology
Organization & Administration	Economics, Legislation & Jurisprudence, Manpower, Standards, Supply & Distribution, Trends, Utilization
Pharmacology	Administration & Dosage, Adverse Effects, Agonists, Antagonists & Inhibitors, Contraindications, Diagnostic Use, Pharmacokinetics, Poisoning, Toxicity
Physiology	Biosynthesis, Blood, Cerebrospinal Fluid, Deficiency, Enzymology, Genetics, Growth & Development, Immunology, Metabolism, Pharmacokinetics, Physiopathology, Secretion, Urine
Statistics & Numerical Data	Ethnology, Epidemiology, Mortality, Supply & Distribution, Utilization
Surgery	Transplantation
Therapeutic Use	Administration & Dosage, Adverse Effects, Contraindications, Poisoning
Therapy	Diet Therapy, Drug Therapy, Nursing, Prevention & Control, Radiotherapy, Rehabilitation, Surgery, Transplantation

OTHER SUBJECTS

KEYWORDS (.KW.): Controlled subject terms assigned by an organization, but not from MeSH. A parenthetical note at the end of the keyword identifies the agency that assigned the term:

KIE = Kennedy Institute of Ethics, Georgetown University
NASA = National Aeronautics and Space Administration
PIP = Population Information Program, Johns Hopkins School of Health

PERSON AS SUBJECT (.PS.): Name of person discussed in the article. Starting in 2002, NLM may now supply the full personal name, with spelled out forenames. Prior to 2002, NLM supplied only initials of forenames. Because there are relatively few occurrences of Person as Subject in the database, we recommend searching by surname alone.

SPACE FLIGHT/MISSION (.SPM.): Space flight or mission name and/or number when results of research conducted in space are covered in the publication.

ABSTRACT

ABSTRACT (.AB.): Omit stopwords when searching AB. Some abstracts carry a parenthetical note that identifies the agency that composed the abstract:

KIE = Kennedy Institute of Ethics, Georgetown University
NASA = National Aeronautics and Space Administration (abstracts written for consumers)
PIP =Population Information Program, Johns Hopkins School of Health

ISSUE NUMBERING

PUBLICATION DATE (.PD.): Date of the journal issue in which the article was published. PD contains year, month or season, and day, if applicable.

YEAR (.YR.): Year of publication of the issue.

MONTH (.MO.): Month or season (and day, if applicable) of publication of the issue. The month is given as a 3-letter abbreviation (Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec). Seasons are spelled out.

VOLUME (.VO.): Volume of the journal in which the article was published.

ISSUE (.IP.): Designation of the issue, part, or supplement in which the article was published.

ARTICLE PAGINATION (.PG.): If you remember the starting page of an article but not the full citation, searching with PG might be useful. Enter the starting page and the truncation symbol $.

CODES

AGE LIMIT (.AGLT.): A phrase describing the human age groups covered by the article, if applicable. To search an age limit, enter the word or entire hyphenated phrase.

Infant-newborn (birth to 1 month)
Infant (1-23 months)
Child-preschool (2-5 years)
Child (6-12 years)
Adolescent (13-18 years)
Adult (19-44 years)
Middle-age (45-64 years)
Aged (65-79 years)
Aged-80-and-over

PUBLICATION TYPE (.AT.): A phrase describing the type of article. To search a publication type, enter the word or entire hyphenated phrase.

Addresses
Bibliography
Biography
Case-reports
Classical-article [for republished seminal articles]
Clinical-conference [for reports of clinical case conferences only]
Clinical-trial [includes all types and phases of clinical trials]
Clinical-trial-phase-I
Clinical-trial-phase-II
Clinical-trial-phase-III
Clinical-trial-phase-IV
Comment [for comment on previously published article]
Comparative-Study
Congresses
Consensus-development-conference
Consensus-development-conference-NIH
Controlled-clinical-trial
Corrected-and-republished-article [consider Published Erratum]
Dictionary
Directory
Duplicate-publication [duplication of material published elsewhere]
Editorial
English-Abstract
Evaluation-studies
Festschrift [for commemorative articles]
Government-publications-guideline [for administrative, procedural guidelines in general]
Historical-article [for articles about past events]
In-Vitro
Interview
Journal-article [excludes Letter, Editorial, News, etc.]
Lectures
Legal-cases [includes law review, legal case study]
Legislation
Letter [includes letters to editor]
Meta-Analysis [quantitative summary combining results of independent studies]
Multicenter-study
News [for medical or scientific news]
Newspaper-article
Overall [collection of articles; consider Meeting Report]
Patient-education-handout
Periodical-index [for cumulated indexes to journals]
Practice-guideline [for specific health care guidelines]
Published-erratum [consider Corrected and Republished Article]
Randomized-controlled-trial
Research-Support-NIH-Extramural
Research-Support-NIH-Intramural
Research-Support-Non-US-Govt
Research-Support-US-Govt-Non-PHS
Research-Support-US-Govt-PHS
Retraction-of-publication [author's statement of retraction]
Retracted-publication [article later retracted by author]
Review
Scientific-integrity-review [U.S. Office of Scientific Integrity reports]
Support-of-Research
Technical-report
Twin-study [for studies of twins]
Validation-studies

COUNTRY OF PUBLICATION (.CP.): The country in which the journal was published.

DATE COMPLETED (.DC.): Date the citation was completed by NLM. The date is formatted YYYYMMDD. For example, 20061017 is October 17, 2006. To find citations completed in a particular month, truncate the date with $ , for example, 200612$ for December 2006.

GRANT/CONTRACT NUMBER (.GC.): Research grant or contract number that designates financial support by any agency of the U.S. Public Health Service or any institute of the National Institutes of Health. These numbers are recorded exactly as they appear in the published article.

ISSN (.IS.): The International Standard Serial Number of the journal.

LANGUAGE (.LA.): A 3-character code identifying the language of the article. For a complete list of codes, see MEDLINE Language Table. Common codes:

eng = English
fre = French
ger = German
ita = Italian
jpn = Japanese
rus = Russian
spa = Spanish

MOLECULAR SEQUENCE (.MS.): Molecular sequence data consisting of the databank name and accession numbers of molecular sequences discussed in the article. This information is added to the MEDLINE citation if it appears in the printed journal article. Databank names:

CSD = Complex Carbohydrate Research Center
GDB = Johns Hopkins University Genome Data Bank
GENBANK = GenBank Nucleic Acid Sequence Database
OMIM = Mendelian Inheritance in Man (McKusick)
PDB = Protein Data Bank
PIR = Protein Identification Resource
PRFSEQDB = Protein Research Foundation
RefSeq
SWISSPROT = Protein Sequence Database

PUBMED UNIQUE IDENTIFIER (.PMID.): Record control number assigned for NLM's PUBMED system; unique to each record in the database. Searching by PMID is a method for returning directly to a record that you have retrieved previously.

REGISTRY NUMBER (.RN.): The name of a chemical substance or enzyme, along with the unique registry number for that chemical or enzyme. The registry number is a 5- to 9-digit hyphenated number assigned to chemical substances by the Chemical Abstracts Service (CAS), or an E.C. number for enzymes derived from Enzyme Nomenclature.

CITATION SUBSET (.SB.): A code that indicates whether the journal is from any of the following categories of journals or specialized topics.

AIM = citations from Abridged Index Medicus journals, a list of about 120 core clinical, English language journals.
D = citations from non-Index Medicus journals in the field of dentistry; these citations appeared in Index to Dental Literature.
E = citations in the field of bioethics (includes records from the former BIOETHICS database).
H = citations from non-Index Medicus journals in the field of health administration (includes records from the former HealthSTAR database).
IM = citations from Index Medicus journals.
K = citations from non-Index Medicus journals relating to consumer health.
N = citations from non-Index Medicus journals in the field of nursing; these citations appeared in the International Nursing Index.
Q = citations in the field of the history of medicine (includes records from the former HISTLINE database).
QIS = citations from non-Index Medicus journals in the field of history of medicine
QO is subset of Q = indicates older history of medicine journal citations that were created before the former HISTLINE file was converted to a MEDLINE-like format (require special handling at NLM).
S = citations in the field of space life sciences (includes records from the former SPACELINE™ database).
T = citations from non-Index Medicus journals in the field of health technology assessment (includes records from the former HealthSTAR database).
X = citations in the field of AIDS/HIV (includes records from the former AIDSLINE database)

The following codes represent closed subsets (no longer being assigned to current data):

B = citations from non-Index Medicus journals in the field of biotechnology (not currently used).
C = citations from non-Index Medicus journals in the field of communication disorders (not currently used).
F = older citations from one journal prior to its selection for Index Medicus; used to augment the database for NLM's International MEDLARS Centers (not currently used)
J = citations from non-Index Medicus journals in the field of population information. (not currently used; on records from the former POPLINE database)
R = citations from non-Index Medicus journals in the field of population and reproduction; these citations appeared in Population Sciences (not currently used).

SUBJECT LIMIT (.SULT.): This field contains any of four values that describe the population covered by the article: humans, animals, male, female. Searching with SULT is the same as using the checkboxes for these terms on the main search page or the limiting page.

February 2007

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