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Bio 1B Research Skills Guide: Scientific Literature: Peer Review

Peer Review

Peer Review

Peer review is the process by which most scholarly journals evaluate articles submitted for publication. The "peer" part of peer review refers to the individuals who evaluate the articles for journals: they are researchers working in the same area as the author—thus, his or her peers.

The peer review process

  • A researcher writes a manuscript describing the results of his/her research and submits it to a journal
  • The editor of the journal makes an initial determination: is the manuscript a good fit for the journal?
  • If so, the editor passes the manuscript along to peer reviewers (other researchers in the same field), who evaluate the manuscript and make a recommendation
  • Reviewers may recommend immediate publication, publication with revisions, or rejection of the manuscript

Reviewers evaluate manuscripts based upon their scientific validity—the literature cited, protocols followed, methods of analysis, and whether conclusions are substantiated by the data presented—as well as the originality and significance of their contribution to the body of scientific knowledge.

Peer review is not a guarantee

Articles that are peer-reviewed have been carefully evaluated by experts in the field, but this doesn't mean that everything in the peer-reviewed literature is proven. Results published in peer-reviewed articles may later be found to be unsound, or may simply be contradicted by new findings. The continual re-evaluation of previous research findings is one of the primary mechanisms by which scientific understanding is advanced.

However, information in the peer reviewed literature has undergone rigorous scrutiny by experts in the field, which is not necessarily true of non-peer reviewed publications. Scientific claims made in the non-peer reviewed literature should be considered with an extra degree of skepticism.

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Finding peer-reviewed articles

Once an article is published in a peer-reviewed journal, it is indexed in article databases like BIOSIS, Web of Science, PubMed, or Scopus. The same journal can be indexed in more than one database.

To locate peer-reviewed articles, search by topic, author or other fields in an appropriate database. See Bio 1B Library Guide: Searching for articles.

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Identifying peer-reviewed articles

Look at the article:

  • Is there an abstract (a summary of the article) at the beginning? Not all peer-reviewed articles have abstracts, but many do.
  • Is there a list of references or literature cited at the end?
  • Is there information about the authors' affiliations? Are they affiliated with universities or other research organizations? Do they have Ph.D.s?

Look at the journal in which the article was published:

  • If online, can you find an "About this journal" link? You can often find out here whether the journal is peer-reviewed or refereed (another term for peer review). Here is an example from the journal PLoS One:

  • Is there an editorial board, and is the board composed mainly of individuals affiliated with universities or research organizations?
  • Does the information for submitting authors mention peer review?

If you are still in doubt, consult a reference librarian.

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Identifying primary research articles

To identify whether an article in a peer-reviewed journal is a primary research article, look for some internal clues:

  • Does the abstract indicate that an experimental study or studies were performed? Does it mention "this study" or include phrases such as "measured," "compared," "determined," "found," etc.?
  • Does the article include a section describing the experimental methods that were followed?
  • Does the article include a section describing the experimental results, usually with data tables and figures​?

​These are all indications that an article is a primary research article ("primary" because the experiments were carried out by the researchers who wrote the article).​

Your Librarian

Elliott Smith's picture
Elliott Smith
Bioscience & Natural Resources Library
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