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Peer Review

What is peer review?

"Editors of scientific journals send papers out for formal evaluation of their intellectual merit by the authors' scientific peers — other scientists, typically anonymous — who work in the same or a closely related field. Peer review is a kind of scientific 'natural selection'; papers that can withstand the scrutiny of this process will find their way to publication and are often substantially stronger for it. Papers that cannot are rejected. Of course, the authors may have the opportunity to resubmit after making further revisions, or they may try their luck by submitting to another journal.

Peer review does not necessarily determine whether the conclusions of a particular study are correct; that may ultimately require further work that either confirms or refutes the conclusions. Instead, the peer review process is designed to prevent the publication of papers so obviously flawed as to be clearly invalid with regard to the claims made or conclusions drawn, and unlikely to add usefully to the scientific discourse” (78-79).

Mann, Michael E. The Hockey Stick and the Climate Wars: Dispatches from the Front Lines. Columbia UP, 2014

"The goals of peer review are both lofty and mundane. It is the responsibility of journals to administer an effective review system. Peer review, as currently practiced by high impact biomedical journals such as Nature Immunology, is designed to select technically valid research of significant interest to, in our case, the general immunology community. Referees are expected to identify flaws, suggest improvements and assess novelty (providing citations of papers that detract from the impact of the paper under review). If the manuscript is deemed important enough to be published in a high visibility journal, referees ensure that it is internally consistent, thereby ferreting out spurious conclusions or clumsy frauds."

Reviewing Peer Review.” Nature Immunology, vol. 4, no. 4, Apr. 2003, p. 297. MEDLINE, doi:10.1038/ni0403-297.

The journal Science accepts less than 7% of papers submitted.

"The Science Contributors FAQ.", American Association for the Advancement of Science, Accessed 19 January 2021.

The rejection rates of journals published by the American Psychological Association vary from 27% to 93%.

Summary Report of Journal Operations, 2019.” American Psychologist, vol. 75, no. 5, July 2020, pp. 723–724. APA PsycArticles, doi:10.1037/amp0000680.

What types of peer review are there?

  • Single blind peer review

Reviewers know the identity of authors, but authors don't know the identity of reviewers.

  • Double blind peer review

Reviewers and authors are anonymous to each other.

  • Triple blind peer review

Editors, reviewers and authors are anonymous to each other.

  • Open peer review

Reviewers and authors are known to each other. Reviewer comments and previous versions of the manuscript are published with the accepted article.

Are all journal articles peer reviewed?

No. Peer-review policies vary for journal publishers. Journal content such as book reviews, letters to the editor, and opinion articles may or may not be peer reviewed.

For example, the peer-review policy of Nature Research states "The following types of contribution to Nature Research journals are peer-reviewed: Articles, Letters, Brief Communications, Matters Arising, Technical Reports, Analysis, Resources, Reviews, Perspectives and Insight articles. Correspondence and all forms of published correction may also be peer-reviewed at the discretion of the editors. Other contributed articles are not usually peer-reviewed."

How do I determine if a journal article is peer reviewed?

There are several possible indicators that a journal article was peer reviewed:

  • The article's author(s) may include an acknowledgements statement that thanks reviewers.


Jones, Philip Edward. “Partisanship, Political Awareness, and Retrospective Evaluations, 1956–2016.” Political Behavior, vol. 42, no. 4, Dec. 2020, pp. 1295-1317. Academic Search Complete, doi:10.1007/s11109-019-09543-y.

  • The journal publisher may include a note indicating when an article was accepted for publication.


Moss, Jonathan, et al. “Brexit and the Everyday Politics of Emotion: Methodological Lessons from History.” Political Studies, vol. 68, no. 4, Nov. 2020, pp. 837-856. Academic Search Complete, doi:10.1177/0032321720911915.

Sometimes the note may also indicate when the article was received by the journal.


Marushka, Lesya, et al. “Potential Impacts of Climate-Related Decline of Seafood Harvest on Nutritional Status of Coastal First Nations in British Columbia, Canada.” PLoS ONE, vol. 14, no. 2, Feb. 2019, pp. 1-24. Academic Search Complete, doi:10.1371/journal.pone.0211473.

Sometimes the note may also indicate when the revised version of the article was received by the journal.


Bleske-Rechek, April, and Michaela M. Gunseor. “Gendered Perspectives on Sharing the Load: Men’s and Women’s Attitudes toward Family Roles and Household and Childcare Tasks.” Evolutionary Behavioral Sciences, Jan. 2021. APA PsycArticles, doi:10.1037/ebs0000257.

  • The journal publisher may provide the peer-review history of an article.


Klebel, Thomas, et al. “Peer Review and Preprint Policies Are Unclear at Most Major Journals.” PLoS ONE, vol. 15, no. 10, Oct. 2020, pp. 1-19. Academic Search Complete, doi:10.1371/journal.pone.0239518.

Are books peer reviewed before they're published?

It depends on the book's publisher. Some publishers peer review book proposals or book manuscripts before they are published. Such publishers include

A book's author(s) may thank reviewers in an acknowledgements statement. Otherwise, a book does not include a statement that it was peer reviewed. To determine whether or not a book was peer reviewed it is necessary to consult a publisher's policy to determine whether it peer reviews its publications.