Peer review is a quality-control process in which experts in a given field evaluate the methodology, analysis, and conclusions of submitted research before publication or funding is awarded. In the context of academic publishing, it typically refers to the assessment of manuscripts by independent specialists prior to their appearance in a journal or edited volume. The process is widely used across the natural sciences, social sciences, humanities, and medicine, though its precise procedures vary considerably by discipline and venue.

Peer review exists in several forms. Single-blind review conceals the identity of authors from reviewers; double-blind review conceals both parties from each other; open peer review makes the identities of both authors and reviewers known, sometimes publishing the review correspondence alongside the article. Post-publication peer review, in which community commentary occurs after a work appears, has grown in visibility with the rise of preprint servers such as arXiv and bioRxiv.

The volume of peer-reviewed literature has expanded substantially since the mid-twentieth century. Major databases such as Scopus and Web of Science index tens of millions of peer-reviewed records. At the same time, the system has come under increased scrutiny. High-profile replication failures in psychology, medicine, and other fields-sometimes grouped under the label of the Replication Crisis-have prompted debate about whether peer review reliably filters out flawed or false findings. The proliferation of predatory journals, which nominally conduct peer review while doing little substantive evaluation, has further complicated assessments of what peer-reviewed status indicates.

Concerns about bias in reviewer selection, including geographic, institutional, and ideological concentration among referees, are documented in the literature on publication bias and reviewer demographics. The largely uncompensated and anonymous nature of traditional peer review has also drawn attention as submission volumes have grown.

There is broad agreement among researchers, editors, and funding agencies that some form of external expert evaluation prior to publication or grant award is necessary and valuable. There is no comparable consensus on which specific form of peer review best achieves reliability, fairness, or reproducibility. Debates over open versus blinded review, the appropriate number of reviewers, and the value of post-publication commentary remain active. See peer-review-consensus-expert-evaluation-consensus.

Peer review as the gold standard of scientific validation. A widely held position treats peer review, especially at high-impact journals, as the primary marker distinguishing reliable scientific knowledge from unvetted claims. Proponents argue that independent expert scrutiny catches errors, deters fraud, and filters out methodologically weak work before it reaches practitioners and the public. See peer-review-gold-standard-viewpoint.

Peer review as a flawed but improvable process. A substantial body of opinion within science studies, bibliometrics, and reform-oriented research communities holds that current peer review practices are unreliable, susceptible to bias, and slow relative to the pace of knowledge production, but that targeted reforms-open review, registered reports, post-publication commentary-can address these failures without abandoning external expert evaluation. See peer-review-reform-viewpoint.

Peer review as a conservative gatekeeping mechanism. Some researchers and historians of science argue that peer review systematically disadvantages heterodox, interdisciplinary, or paradigm-challenging work by empowering established figures to suppress challenges to dominant frameworks. This viewpoint draws on documented cases of initially rejected work that later proved significant. See peer-review-gatekeeping-viewpoint.

Peer review as insufficient for detecting fraud and error. A narrower but well-documented position holds that peer review was never designed to catch deliberate fabrication or subtle methodological manipulation, and that treating it as a fraud-detection mechanism creates false confidence. Proponents often support complementary mechanisms such as data sharing mandates, registered replication, and statistical audit. See peer-review-fraud-detection-limits-viewpoint.

The Sokal Affair and hoax submissions. A series of episodes, beginning with physicist Alan Sokal's 1996 submission of a deliberately nonsensical paper to the journal Social Text and extending through later sting operations targeting both humanities and open-access science journals, raised documented questions about whether peer review in specific venues or disciplines was capable of detecting fabricated or incoherent work. See peer-review-hoax-submissions-controversy.

Replication crisis and peer review's role. The failure of significant proportions of published findings in psychology, medicine, and cancer biology to replicate under independent testing generated documented disputes among researchers, journal editors, and funding bodies about the degree to which peer review bears responsibility for the underlying problems. See peer-review-replication-crisis-controversy.

Predatory journals. The growth of publishers that collect article processing fees while conducting minimal or no genuine peer review has produced ongoing disputes over enforcement, indexing, and the adequacy of current regulatory and accreditation frameworks. See peer-review-predatory-journals-controversy.

• peer-review-history
• peer-review-debate-open-vs-blind-debate
• peer-review-debate-post-publication-vs-prepublication-debate
• peer-review-gold-standard-viewpoint
• peer-review-consensus-expert-evaluation-consensus
• peer-review-hoax-submissions-controversy
• peer-review-replication-crisis-controversy
• peer-review-predatory-journals-controversy
• Replication Crisis
• scientific-fraud
• open-access-publishing
• publication-bias

1. Biagioli, Mario, Alexandra Lippman, eds. Gaming the Metrics: Misconduct and Manipulation in Academic Research. Cambridge, MA: MIT Press, 2020.

2. Burnham, John C. “The Evolution of Editorial Peer Review.” JAMA 263, no. 10 (1990): 1323-1329.

3. Fanelli, Daniele. “How Many Scientists Fabricate and Falsify Research? A Systematic Review and Meta-Analysis of Survey Data.” PLOS ONE 4, no. 5 (2009): e5738.

4. Godlee, Fiona, Catharine R. Gale, and Christopher N. Martyn. “Effect on the Quality of Peer Review of Blinding Reviewers and Asking Them to Sign Their Reports.” JAMA 280, no. 3 (1998): 237-240.

5. Ioannidis, John P. A. “Why Most Published Research Findings Are False.” PLOS Medicine 2, no. 8 (2005): e124.

6. Jefferson, Tom, Philip Alderson, Elizabeth Wager, and Frank Davidoff. “Effects of Editorial Peer Review: A Systematic Review.” JAMA 287, no. 21 (2002): 2784-2786.

7. Open Science Collaboration. “Estimating the Reproducibility of Psychological Science.” Science 349, no. 6251 (2015): aac4716.

8. Sokal, Alan D. “Transgressing the Boundaries: Toward a Transformative Hermeneutics of Quantum Gravity.” Social Text 46/47 (1996): 217-252.

9. Tennant, Jonathan P., François Waldner, Damien C. Jacques, Paola Masuzzo, Lauren B. Collister, and Chris H. J. Hartgerink. “The Academic, Economic and Societal Impacts of Open Access: An Evidence-Based Review.” F1000Research 5 (2016): 632.