Peer review is the process by which scientific content is assessed based on its academic integrity and originality. Originating in the scientific circles of the 17th, 18th, and 19th centuries, peer review has since developed into a foundation for maintaining scientific standards. Its widely implemented principles and procedures aim to ensure that only quality and ethically sound information enters the research ecosystem.
But what exactly does it mean for research to be peer-reviewed? And where does the peer review model fall short? We’ll try and answer these questions, as well as discuss how peer-reviewed articles compare to preprints and why community peer review may complement and even strengthen the traditional scholarly review model.
What does ‘peer reviewed’ actually mean?
Peer review is a standardised method of evaluating scientific research with a view to understanding its potential impact if it were to be published. It typically involves one or two external reviewers with expertise in the relevant subject area providing detailed feedback on scholarly articles submitted to journals.
For an article to be classed as ‘peer reviewed’, it needs to have successfully passed this period of evaluation. The scientific content and the originality of the argument are evaluated and improvements recommended if appropriate. The peer review period can take anywhere from a few months to a year, depending on factors such as rounds of assessment needed and reviewer availability.
For more information, see our article on what ‘peer reviewed’ actually means.
Types of peer review
Peer review has evolved alongside scientific communication. This evolution of the peer review process has resulted in distinct types.
Single-blind peer review
This type is perhaps most closely aligned with what is commonly known as ‘peer review’. Single-blind peer review means the reviewers know the authors, but the authors do not know the identity of the reviewers.
This arrangement ensures authors cannot influence reviewers, but it may also carry risk of bias. Since the reviewers know the identity of the authors, their nationality, institutional prestige, and scholarly reputation could influence the decisions of reviewers, although situations like this are rare and typically contained by ethical parameters.
Double-blind peer review
In the double-blind peer review arrangement, neither the authors nor the reviewers know the identities of the other parties. This is arguably the most neutral reviewing model, with affiliations, names, and positions removed, leaving only the research to be evaluated.
Open peer review
Open peer review is an umbrella term for the various open practices used during the peer review process. Examples of open peer review practices include:
- Open reports: The review process is made public along with the published research.
- Open identities: The identities of the author and reviewer are known to each other, and the reader.
- Open participation: The scientific community is encouraged to leave comments on research post-publication.
- Open interaction: Authors, reviewers, and other researchers are free to interact and discuss.
Open participation, or community peer review, is a key element of preprint-based research assessment. We will return to it in more depth later in the article.
Preprints vs. peer-reviewed articles
Preprints are markedly different to traditional peer-reviewed articles. Here are some of the key areas where they differ:
- Reviewing process
- Speed of publication
- Accessibility
- Permanence and versioning
A preprint is essentially a draft of a scholarly article or research paper, made freely accessible online prior to formal review. Preprints are distinct from peer-reviewed articles in that they don’t undergo a traditional review process.
For this reason, preprints typically have a much faster posting turnaround time than peer-reviewed articles. Traditional peer review cycles can last for months depending on journal-dependent factors out of the author’s hands. Preprints are typically posted on Preprints.org after a short screening process. This usually takes around 24 working hours (unless necessary information is missing).
Despite foregoing traditional peer review, preprints are still subject to screening for basic scientific soundness, ethics, and plagiarism. The critique of the content may not be as rigorous as it is with peer-reviewed articles. But preprints are still held to the same ethical standards.
In terms of accessibility, preprints posted on Preprints.org are open access and free to read and upload. Final journal articles may be hidden behind paywalls, unless the journal uses a hybrid publishing model or gold open access model that allows it to pay fees to make certain articles open access.
Finally, preprints can be updated to reflect new information at any point after posting through a process known as ‘versioning.’ Peer-reviewed articles represent a stable ‘version of record’ that cannot be updated post-publication. They may be retracted due to examples of research misconduct, scientific inaccuracy, plagiarism, etc.
For more information, see our article on preprints vs. peer-reviewed articles.
Community peer review: how preprints enable open scholarly discussion
Community peer review is an open and collaborative method of evaluating research. It typically refers to assessment carried out by a broader pool of researchers (compared to the two or three experts during the closed peer review process) who can read, publicly comment, critique, and in some cases formally endorse research, often before formal journal submission. This model increases transparency, speed and scope of feedback, and democratic participation in the evaluation of science.
When preprints are posted to online servers like Preprints.org, they are made freely and immediately accessible via Creative Commons licensing. Researchers from around the world can leave early feedback, helping to provide diverse perspectives and shape the research manuscript.
Important to remember is that community peer review does not replace formal peer review; it complements and strengthens it. The process expands who gets to evaluate science. Consequently, it diversifies the reviewer pool and reduces long-term strain on overburdened journal reviewers. It further highlights the importance of reviewer training, helping to make formal mentorship programs more established within the scientific community. Most importantly of all, however, is how community peer review makes the quality assurance process more transparent and accountable.
For more information, see our article on community peer review.
Open peer review: pros and cons
Open or transparent peer review – of which community feedback and preprint-based research assessment are features – has its own broader pros and cons to consider, some of which we have already touched upon. Here are the main ones:
Pros
- Promotes collaboration: By opening up research to constructive criticism beyond traditional peer review, both authors and readers can collaborate to improve the outcome of the research.
- Engages scholarly communities: Whereas traditional peer review limits research to the discussion of a select few experts, open peer review has the potential to engage entire communities by making the evaluation of certain topical papers a visible, communal event.
- Supports learning and development: Review reports being available alongside publications enables other scholars to learn from other examples before going through the peer review process themselves.
Cons
- Concerns over thoroughness: Since their review reports are accessible to all, reviewers may temper their criticisms for fear of being rebuked by the scientific community.
- Assessment quality varies: As open peer review allows the wider research community to participate and provide feedback, the quality and depth of assessment may vary depending on participants’ expertise and engagement.
- Recognition and incentives remain limited: More efforts are needed to provide meaningful recognition and incentives for authors to participate in open peer review and for reviewers to contribute their feedback.
Open peer review is a practice not without its limitations and concerns. But as a principle and method of increasing transparency and speed during the review process, it’s fundamental to the acceleration of scientific progress. Those wishing to engage with preprint-based research assessment should be aware of the preliminary nature of findings and the responsibilities of reviewers.
For more information, see our article on open peer review and preprints: pros and cons. For those wishing to post a preprint, see our article on the benefits of posting a preprint for authors.
