Research Techniques

MeSH - Medical Subject Headings

MeSH is a controlled vocabulary of standardized terms that describe the main content of articles. Terms are chosen to cover both the central aspects of an article (major headings) and other significant information discussed (minor headings).

MeSH is used to identify relevant search terms to your concepts, to apply subheadings and focus the search. I can also help limit or expand retrieval. MeSH can also be used to search by a subject and to build a search strategy in the advanced search builder. MeSH terms help account for variations in language, acronyms, and British vs. American English.

Terms are arranged hierarchically by subject categories with more specific terms arranged beneath broader terms. MeSH terms in PubMed automatically include the narrower MeSH terms in a search. This is called "explode."

Search MeSH database:

• On the homepage, click on MeSH Database under the search bar .
• Type the keyword and search .
• Click on the appropriate heading, it will open a new page that includes the subheadings and the MeSH Tree .
  • If you would like to choose all subheadings, leave them all unchecked and click on "Add to search builder" then search for another MeSH term . 
  • Or select one or more subheadings to limit the search results. 
  • You can choose not to include any subheading in the search by selecting "Restrict to MeSH Major Topic"
• When done adding Mesh terms to search builder, click on Search PubMed.

For comprehensive research, it is recommended to combine MeSH terms and keywords in the search (syntax).

Export References to Citation Management Tools

Export from PubMed

Specific references

On the results' page, select the references you want to export, click on Send to, then select Citation Manager, then click on Create file .

All the references

• Keep all references unselected
• Click on Send to
• Select Citation Manager
• Choose an option from the drop down menu
• Click on Create file, you will receive a confirmation message on the screen

Import to RefWorks

• Log in to your RefWorks account
• Click on +Add
• Select "Import References"
• Choose the file downloaded from PubMed

For assistance in using RefWorks, please refer to the RefWorks guide by HBKU Library.

Import to other citation management softwares

Whether you are using EndNote, Mendeley, Zotero and other citation management softwares, the steps are similar: adding references by uploading the RIS file you have downloaded from PubMed.

Mendeley: click on "Add new" then select "Files from Computer"

Zotero: Click on File in the Menu, select Import and choose RIS file and follow instructions on the screen .

The Single Citation Matcher in PubMed allows you to search for a particular citation, especially when you have only a little information about the article. It is accessible from the homepage .

Example: If you are looking for an article in the International journal of cancer about lymphoma but you don't remember the title nor the author, but you know it was published in 2020.

Enter the information you have in their respective fields and search.

Refine Search Results

NCBI provide several filters to refine the search results with, starting by the date of publication, article type, and additional filters like age, sex, language and more .

You may consider refining your results by amending the search as needed:

For more results, broaden the search by:

• "Exploding" your terms  or including more subheadings
• Adding keywords and combining synonyms with OR (synonyms=search terms for the same concept)
• Using broader terms
• Using truncation or proximity search
• Expanding date range to cover more years
• Expanding the population (covering all genders, ethnicities, age groups, etc.)

For less results when you get too many, narrow down your search by:

• Restricting your MeSH terms to Major Topic (opposite to "exploding") or specifying a few subheadings
• Removing keywords
• Narrowing down the date range and location (one country instead of a continent, a state/city instead of a country. etc.)
• Limiting the population to a smaller age group, specify the gender, etc.
• Using phrase search
• Removing truncation if used
• Searching by specific field(s).

Clinical Queries "uses predefined filters to help you quickly refine PubMed searches on clinical or disease-specific topics" (PubMed/Clinical Queries).

Access Clinical Queries from the homepage  and enter your search terms. The built-in research methodology search filters are intended for clinicians.

Choose one of the five study categories or filters listed: etiology, diagnosis, therapy, prognosis, and clinical prediction guides.

Two filters are available: broad, sensitive search (includes relevant articles but probably some less relevant) and narrow, specific search (more precise articles, with less retrieval) .

At the end of the results in the clinical queries page, you can be check more results and refine them on PubMed results page using the filters.