BTEC 620: Molecular Biology

Finding Primary Sources in PubMed

How to search PubMed to find primary research published since 2000, how to get the full-text articles, and how to find "high impact" journals.

Tips and Strategies

Enter your concepts into the PubMed search box.

• TIP: it can be useful to enter only one concept at a time, to be sure each new addition retrieves results.
  • EXAMPLE: enhancer RNA

Tips to focus your search: 

• Add additional terms to narrow the search
  • EXAMPLE: add gene expression to the search:
    • enhancer RNA AND gene expression
• Consider entering phrases in quotation marks to find only that exact phrase.
  • EXAMPLE: "enhancer RNA" AND "gene expression"
• Consider whether there are synonyms or other terms similar to the keywords you are using, and add them to the search using the "OR" operator, and use parentheses () to group similar concepts or keywords together.
  • EXAMPLE: ("enhancer RNA" OR eRNA) AND "gene expression"
    • TIP: the "AND" operator is optional, as PubMed applies it automatically.

Limit your search results by publication date:

• We want to limit to articles published since 2000.
  • EXAMPLE: At the top of the left-hand sidebar, use the date slider to select the date range: 2000 - 2024.
    • TIP: you can expand the size of the slider using the expand button.
  • You can also use the "publication date" filter at the bottom of the sidebar to create a "Custom Range" of years.
  • TIP: If you're using a small screen and do not see a sidebar, look for the "filters" button in the top menu.

What about "Review" articles?

• "Review" articles are not primary research, but they can be excellent sources to identify relevant primary research articles.
• If you wish to remove the "review" articles from your search results, use the "Advanced" search link below the search box.
  • Select your original search from the search history, and add it to the query using the search #.
    • EXAMPLE: add search #4
  • From the search fields dropdown menu, choose "Publication Type," and enter "Review" into the search box, and choose "Add with NOT" from the "Add" dropdown menu. 
    • EXAMPLE search string: (#4) NOT ("Review"[Publication Type])

Identify primary research articles.

• Look for evidence of primary research in the article abstract, or in the body of the article:
  • The authors conduct the study. The article will report the results of research conducted by the authors to answer a research question or test a hypothesis.
    • Look for words indicating that the authors themselves "measured" or "analyzed" or "Investigated" the topic at hand.
  • Methods section. The article will usually have a "methods" or "methodology" or "research design" section detailing how the research was conducted or performed.
  • Results section and data visualizations. The article should include a "results" section that reports the authors' original findings.
    • Look for statistics, graphs, tables, or other data visualizations here.

Finding the Full Text of an article:

• Click on an article title to view the full record in PubMed.
  • Check the full text links / buttons in the right-hand sidebar.
    • If the link / button says "PubMed Central" or "PMC" or "open access" or "free" then the full text will be available.
      • Otherwise, you may see a link to the publisher's website where you can check to see whether or not the full text is available for free.
    • Always check Gleeson Library's "Full Text Finder" which will let you know if you have access to the full text via the library databases and subscriptions.
    • TIP: You must access PubMed via the library's link in order for the library's "Full Text Finder" to appear.
  • If there is no full text available anywhere, you can use the library's Interlibrary Loan service to request the article from another library. This is free for you, and we can usually get articles very quickly.

High Impact Journals

How to determine if an article is published in a "high impact" journal.

"Impact" for journals refers to how influential the journal is in a discipline compared to other journals in the same discipline; this is based on how frequently the journal's articles are cited or referenced by other research articles.

You can investigate this kind of "impact" using a database called "Scopus."

• In Scopus, click on the "Sources" menu at the top of the page.
  • Select "Title" from the dropdown menu, and enter the title of the journal that you would like to investigate.
  • EXAMPLE: Biomarkers
    • click on "Biomarkers" in the results list to see that the journal is ranked in the middle of the pack in three different disciplines, so by this measure, it is neither particularly "high impact" nor "low impact."

APA Citations and RefWorks

Cite your articles in APA format

• PubMed can help you cite your articles in APA format.
  • EXAMPLE: In PubMed, click on the title of the article to display the full record, and then click on the "Cite" button in the right-hand sidebar. 
    • Change the "format" to APA, and copy / paste the result.
• TIP: with any online-generated citation, you always need to examine the citation for accuracy.

For a full-featured citation manager that can format APA style as well as thousands of other styles, see RefWorks, below.