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PubMed is a free interface for searching MEDLINE, the most popular bibliographic database in the health and medical sciences. It contains references to millions of journal articles from biomedical journals and is updated daily.

Expanding your search

If you are finding too few relevant references then you may need to look at expanding your search. 

You can use the following features to help you identify further articles which may be of interest:

You can also experiment with broadening your search terms and adding synonymous terms into your search strategy.

Of course, it may just be that there is very little written on your topic! Ask a librarian for advice if you require further help with your search.  

Similar Articles

When looking at the abstract page of a record, you may see that PubMed suggests Similar Articles to the article that you are looking at. 

PubMed uses a word-weighted algorithm to compare MeSH headings and words from the Title and Abstract of each citation in PubMed. The best matches found by this algorithm for each citation are then stored and recommended as Similar Articles

Some citations will not yet have Similar Articles links because they have not yet gone through the algorithm process. For more information see PubMed's detailed guide to how Similar Articles are computed

Cited by link imageCited reference searching

PubMed offers cited reference searching which can be a useful way of expanding the list of references you have found, by finding more recent articles that have cited the article you are looking at. You can view Cited By links by looking at the bottom of a reference when your results are displayed in abstract view. The full record of an individual article also contains a list of Cited by articles. 

Important: Cited by information is generated using data submitted by publishers and from NCBI resources such as PubMed Central.  If you need to undertake a more comprehensive citation search or citation analysis then we recommend using a specialised citation database such as the following: