PubMed (EN): 2. Medical Subject Headings (MeSH)

Medical Subject Headings are terms that are separately added to an article by PubMed. These terms are comparable to a hashtag on platforms such as twitter or Instagram. With these tags you can find related articles. The MeSH-terms is the preferred term for a phenomenon by PubMed.

MeSH advantages:

• The MeSH-terms are always an important aspect of the article;
• With one term you can find articles that use various synonyms for a phenomenon;
• Narrower terms are automatically added to your search;
• With the MeSH you can also find articles without an abstract. 

MeSH disatvantages:

• MeSH terms are manually added and may contain human-made errors;
• Some phenomena such as specific or new subjects do not (yet) have their own MeSH term;
• Some of the newly published articles do not yet have added MeSH-terms, this takes about 6 to 8 weeks. 

The largest difference between PubMed and other databases is the way they use thesaurus terms, in the case of PubMed the MeSH terms. Other databases may choose to use different thesaurus terms, depending on their field of focus and preference.

PubMed also automatically includes MeSH-terms that are found lower in the MeSH hierchy. In many other databases you have to specify that you also want to include these terms. 

The easiest way to find relevant MeSH-terms is to go to the PubMed home page. Under the heading 'explore' you can find the link to the MeSH database. In the MeSH query box you can enter a term from one of the elements of your research question. It is wise to try several synonyms of spelling variants here to find a suitable MeSH-term. If you have already found a possibly relevant article you can also check wheter this article has any relevant MeSH-terms registered to it. 

If you click on one of the suggested MeSH-terms you will see a new page containing the following items:

• A brief description of the MeSH-term;
• An overview of the place in the MeSH-hierchy: which broader and narrower terms are related
• A list of entry-terms: possible synonyms or terms related to the MeSH. 

It is useful to copy the Entry terms and to place them in a separate word-document. You can use these terms as possible synonyms to search for in the title and abstract during the next step. 

If you want to use the MeSH term in your search you can click the buttons 'add to search builder', followed by 'search pubmed ' in the top right corner of the MeSH menu. PubMed will now search for the MeSH term and place it in the search history to be used later.