PubMed Labs is a new initiative from the National Center for Biotechnology Information (NCBI).
Learn About: PubMed Labs.
From an NCBI Blog Post:
PubMed is free, but finding the important articles on a topic can cost a lot of time. To help you keep on top of the literature – with a little help from your fellow PubMed users – we are introducing a new type of link called “Articles frequently viewed together”. For some PubMed abstracts, you may see this link in the “Related Information” section in the right column.
Not all abstracts will have this link; currently, only 1.3 million out of the 24 million records in PubMed do. The calculation is based on anonymous click data for the last year, so older articles will be especially underrepresented. To find all articles with these relationships, search PubMed with the query “pubmed_pubmed_alsoviewed[filter]”. Add additional terms to narrow the focus to your area of interest.