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Glossary for PubMed and Medline

Read definitions and quick facts for some of the jargon you will see in these databases.

Description

PubMed and Medline are some of the most useful databases for most health sciences topics, but they use some jargon. Use the list below to check what each word or phrase means. The list is in alphabetical order according to the English language.

Broader MeSH Terms

Broader MeSH terms are more comprehensive ideas than the MeSH term you chose. They are less specific than MeSH terms. Sometimes, you may decide to use the broader MeSH term instead of the MeSH term you originally chose. Consider using the broader MeSH term if you do not find enough articles with the MeSH term you started with.

The MeSH term you started with will be indented underneath the broader MeSH terms.

In PubMed, you may see multiple sections with broader MeSH terms.

Broader MeSH terms appear for most, but not all, MeSH terms.

Definition

Also known as "Scope."

The definition explains what the MeSH term means. It helps you decide if this MeSH term is useful for your search or not. You can often find related ideas in the definition. If any parts of the definition are also MeSH terms, those words will be written in capital letters.

Entry Terms

Also known as "Used for"

These words are synonyms for the MeSH Term. If you type one of these search terms into the MeSH search bar, you will get the corresponding MeSH term in your results. You can use this list to find other ways to refer to your idea.

Explode

Exploding means to include any narrower MeSH terms in your search. (Exploding Edema is the same as searching for Edema OR Edema, Cardiac OR Hydrops Fetalis.) 

PubMed automatically explodes your search for you. You must tell it if you do NOT want to explode your search. In Ovid Medline, you must select the "Explode" box if you want to include the narrower search terms. Your search history will look different in PubMed than in Ovid. 

PubMed will not use any special marking to show that you have exploded your search. Your search history in PubMed will use [Mesh:NoExp] if you choose to not explode your search.

Your search history in Ovid Medline will use exp before your MeSH term to show that you exploded the search. It will not use any special marking to show that you decided to only search for the main MeSH term. 

Focus

Also known as "Restrict to MeSH Major Topic"

Focusing your search means to display only articles where the subject heading you have chosen is the main idea of the article. You rarely need to use this tool for the searches you do at MCPHS.

Your search history in Ovid Medline will use * before your MeSH term to show that you focused the search. (For example, *Heart) It will not use any special marking to show that you have not focused a search.

Your search history in PubMed will use [Majr] after your MeSH term and subheadings to show that you focused the search. (For example, Heart [Majr] or Heart/parasitology [Majr]). It will not use any special marking to show that you have not focused a search.

Indexed

To index something is to include in a database or list and (usually) to identify its subject(s). When a journal is indexed in Medline, Medline has citations for the articles in the journal. Each article is also tagged with relevant subject headings. 

Medical Subject Headings

Medical Subject Headings, also known as MeSH, are predefined ways to refer to specific topics. Instead of typing several synonyms for an idea, you only need to select the appropriate Medical Subject Heading. For example, instead of typing "fever OR pyrexia OR hyperthermia," you can use the MeSH term "Fever." Medical Subject Headings range from broad concepts, like "Chemicals and Drugs Category," to narrow concepts, such as "Warfarin." 

Medline

Medline is a carefully curated biomedical database. It is one part of PubMed. The articles in Medline have been assigned Medical Subject Headings (MeSH terms) to make them easy to find.

MeSH

MeSH stands for Medical Subject Headings. You use MeSH to search Medline.

MeSH Hierarchy

Also known as MeSH Tree.

The MeSH Hierarchy organizes MeSH terms from broad concepts to narrow concepts. You can use the MeSH Hierarchy to find broader, more specific, or related terms.

MeSH Term

There may be several different ways to identify the same idea. The MeSH term is the way that the National Library of Medicine has chosen to use.

MeSH Tree

Also known as the MeSH Hierarcy.

The MeSH Tree organizes MeSH terms from broad concepts to narrow concepts. You can use the MeSH Hierarchy to find broader, more specific, or related terms.

Narrower MeSH Terms

Narrower MeSH terms are more specific types of the MeSH term you chose. For example, Iofetamine is a type of Amphetamine). Consider using a narrower MeSH term if you find too many articles with the MeSH term you started with. Narrower MeSH terms will be indented underneath the term you started with.

In PubMed, a search for the MeSH term will automatically also search for the narrower MeSH terms unless you select the “Do not include MeSH terms found below this term in the MeSH hierarchy” option. In Ovid Medline, you must select the "Explode" box if you want to include the narrower search terms.

Narrower MeSH terms appear for many, but not all, MeSH terms.

PMC

PMC is an abbreviation for PubMed Central.

PubMed Central provides free full-text for articles about research funded with federal grants, articles that publishers decide to make freely available in PubMed Central, and articles that authors decide to make freely available in PubMed Central.

You may find citations in PubMed Central up to one year before the actual article is available there. Federal rules give authors and publishers a whole year to make articles about federally-funded research available in PubMed Central.

If an article is in PubMed Central, you will also find a citation for it in PubMed.

PMCID

The PMCID is a number that identifies a specific article in PubMed Central's system. You can use it to quickly search for a specific article in PubMed Central. The PMCID will start with the letters PMC. For example, PMC4816557 is the PMCID for the article

Shi X, Walter NA, Harkness JH, Neve KA, Williams RW, Lu L, Belknap JK, Eshleman AJ, Phillips TJ, Janowsky A. Genetic Polymorphisms Affect Mouse and Human Trace Amine-Associated Receptor 1 Function. PLoS One. 2016 Mar 31;11(3):e0152581. doi: 10.1371/journal.pone.0152581.

PMID

The PMID is a number that identifies a specific article in PubMed's system. You can use it to quickly search for a specific article in PubMed. For example, 27031617 is the PMID for the article

Shi X, Walter NA, Harkness JH, Neve KA, Williams RW, Lu L, Belknap JK, Eshleman AJ, Phillips TJ, Janowsky A. Genetic Polymorphisms Affect Mouse and Human Trace Amine-Associated Receptor 1 Function. PLoS One. 2016 Mar 31;11(3):e0152581. doi: 10.1371/journal.pone.0152581

You can find PMIDs listed in many databases besides PubMed.

Previous Indexing

This section tells you how to find articles about this topic that were published before the MeSH Term was created. Often, these older MeSH terms are broader; it may take more work to find relevant articles using these previous indexing terms. The years each term was used for this topic are listed in parentheses.

Previous indexing appears for some, but not all, MeSH terms.

PubMed

PubMed is a huge database you can use to find articles about medicine, biology, health, and related disciplines. PubMed includes Medline, articles in PubMed Central, books, and many other types of content.

PubMed Central

PubMed Central provides free full-text for articles about research funded with federal grants, articles that publishers decide to make freely available in PubMed Central, and articles that authors decide to make freely available in PubMed Central.

You may find citations in PubMed Central up to one year before the actual article is available there. Federal rules give authors and publishers a whole year to make articles about federally-funded research available in PubMed Central.

If an article is in PubMed Central, you will also find a citation for it in PubMed.

Restrict to MeSH Major Topic

Also known as "Focus"

Restricting your search to MeSH major topics means to display only articles where the subject heading you have chosen is the main idea of the article. You rarely need to use this tool for the searches you do at MCPHS.

Your search history in PubMed will use [Majr] after your MeSH term and subheadings to show that you restricted your search to MeSH major topic. (For example, Heart [Majr] or Heart/parasitology [Majr]). It will not use any special marking to show that you have not restricted your search to MeSH major topic.

Your search history in Ovid Medline will use * before your MeSH term to show that you restricted the search to the MeSH major topic. (For example, *Heart) It will not use any special marking to show that you have not restricted a search to a MeSH major topic.

Scope Note

A Scope Note tells you helpful information, such as the definition of a MeSH term, synonyms for it, and when this MeSH term was first created. In Ovid, click the information button next to the MeSH term to access the scope note.

See Also

Also known as "See Related"

See Also references are terms that closely related to the MeSH term, but are not synonyms. They may be MeSH terms that are frequently applied to the same articles as the MeSH term.

See Also references appear for some, but not all, MeSH terms.

See Related

Also known as "See Also"

See Related references are terms that closely related to the MeSH term, but are not synonyms. They may be MeSH terms that are frequently applied to the same articles as the MeSH term.

See Related references appear for some, but not all, MeSH terms.

Selectively Indexed

If a journal is selectively indexed in Medline, it means that only some of the articles relate to biomedicine. Staff members at the National Library of Medicine will enter citation information for all articles into PubMed. They will only tag the relevant articles with subject headings (MeSH terms).

Subheadings

These options let you focus on specific aspects of your topic, such as diagnosis or mortality. You can select one or more subheadings to use in your search. You do not have to select a subheading.

One or more subheadings will appear for most, but not all, MeSH terms. Different MeSH terms will show different subheading options.

You will know that you used a subheading in your search if you get anything immediately after the slash mark (/) in your search history. (For example: "Heart/innervation"[Mesh] or Insulin/tu [Therapeutic Use])

Subject Heading

A subject heading is a tool that helps you quickly find articles on your topic. Different people use different words to refer to the same idea. (For example, some people will use the word seizures and others will use the word convulsions). People who create a database select one of those words and always use that word to refer to the idea. (For example, the National Library of Medicine has chose "seizures"). The people who create the database will then tag relevant articles with this subject heading, even if the article used a different word or phrase. You can search for the subject heading to find those articles.

In Medline, the subject headings are known as MeSH terms (Medical Subject Heading terms).

Supplemental Concept

Supplemental concepts refer to chemicals and substances that many articles include but that are not yet common enough to be turned into official MeSH terms. You can think of them as seeds for MeSH terms.

Used For

Also known as "Entry Terms"

These words are synonyms for the MeSH Term. If you type one of these search terms into the MeSH search bar, you will get the corresponding MeSH term in your results. You can use this list to find other ways to refer to your idea.

Year Introduced

(Also known as "Year of Entry.")

This note tells you when this MeSH term was first created. As medical research changes, new MeSH Terms are added to cover the new concepts, to make it easier to find hot topics, and to reflect current thinking. The MeSH term will only help you find articles published after this date.

This note will appear for many, but not all, MeSH terms.

Year of Entry

(Also known as "Year Introduced.")

This note tells you when this MeSH term was first created. As medical research changes, new MeSH Terms are added to cover the new concepts, to make it easier to find hot topics, and to reflect current thinking. The MeSH term will only help you find articles published after this date.

This note will appear for many, but not all, MeSH terms.

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