Types of Peer Review

Peer review is a process used by researchers to evaluate the quality and validity of academic research papers before they are published in a journal. In this process, an author submits their work, which is then evaluated by a panel of experts in the same field, known as peers or referees. These reviewers evaluate the paper based on its scientific quality, novelty, and relevance to the field.

Peer reviewers assess the paper's strengths and weaknesses, suggest improvements, and determine whether it meets the journal's publication standards.

There are many types of peer review processes. The review process can be anonymous, with the reviewers providing feedback through the journal, or open, with the reviewers identity available to the author.

Peer review is an important aspect of the academic publishing process. It helps ensure that research submitted for publication is of high quality and meets the standards of the academic community. It also helps to uphold the ethics and credibility of the academic field by providing quality control.

In this article, we will review the most common types of peer review processes. We will also discuss some pros and cons of each.

1. Single-blind peer review (Single anonymized)

In single-blind peer review, the identity of the author of a scholarly work, such as a research paper or grant proposal, is hidden from the reviewers who evaluate the work. In other words, the reviewers are aware of the author's name and affiliation, but the author doesn’t know the identity of the reviewers.

Single-blind peer review is commonly used in academic publishing, especially in the sciences and social sciences. In this process, the reviewers provide feedback on the manuscript, including its methodology, analysis, and conclusions, and may suggest revisions or improvements to strengthen the work.

Pros: The purpose of single-blind peer review is to reduce potential bias in the review process. By hiding the author's identity, the reviewers are less likely to be influenced by factors such as the author's reputation, institution, or country. This helps ensure the work is evaluated on its quality and scientific rigor and not on the author's identity.

Cons: Single-blind peer review can reduce bias in the review process. However, some argue the identity of the reviewers should also be hidden to reduce potential reciprocal bias. This is when reviewers are influenced by their relationships with the authors. Double-blind peer review, where the identities of both the authors and reviewers are hidden, is an alternative process that is gaining popularity in some academic fields.

2. Double-blind peer review (Double anonymized)

Double-blind peer review is a process used by academic journals to ensure articles submitted for publication are fairly reviewed by experts in the field. In this process, both the authors’ and the reviewers’ identities are hidden from each other.

Pros: Hiding the identity of both the authors and the reviewers is done to prevent bias on both sides. Reviewers might be more or less critical of an article if they know the author's identity or affiliation, and authors might be more or less likely to submit to a journal if they know who the reviewers are. It is commonly considered to be one of the most effective ways to ensure the quality and fairness of the peer review process.

Cons: Double-blind peer review can be time-consuming and expensive. It requires more effort to ensure anonymity and confidentiality throughout the process. 

Additionally, a recent study published in the American Journal of Obstetrics & Gynecology found that the double-blind peer review process seemed to be associated with an 18% lower manuscript acceptance rate than the single-blind peer review process.

3. Triple-blind peer review

Triple-blind peer review is a variation of the double-blind peer review process. In this process, the identities of not only the authors but also the editors handling the manuscript are hidden from the reviewers. In addition, the identities of the reviewers are hidden from the authors.

Pros: Triple-blind peer review aims to eliminate potential bias that could arise if the editor's identity was known to the reviewers. By keeping the editor's identity hidden, the review process becomes more fair and objective.

Cons: This review process is new and less common than the double-blind review. It requires additional resources and effort to maintain anonymity throughout the process.

For a more in-depth discussion about peer review, see our recent Peer Review Survival Skills ebook.

4. Open peer review

Open peer review is a relatively new peer review process. In open peer review, the identities of authors and reviewers are revealed, and the review comments are made public. The anonymity in the traditional peer review system is removed, and the authors, reviewers, and readers can interact with each other.

Pros: Open peer review can promote transparency and accountability in the review process. It can also increase the quality of peer review by encouraging constructive feedback from a broader range of people, including non-experts. Open peer review allows reviewers to be recognized for their work. This can encourage them to provide more thoughtful and thorough reviews. 

Open peer review can be performed in various ways. For example, some journals may reveal the identities of the authors and reviewers but only share the review comments with the authors. Others may publish the review comments and the authors' responses alongside the published article, creating a dialogue between the authors, reviewers, and readers. Open peer review can also be combined with other review processes, such as double-blind or triple-blind peer review, to improve the quality of the review process.

Cons: Reviewers may be less likely to provide honest, critical feedback if their identity is known to the authors. This may be particularly true if the reviewers are junior researchers or if the authors hold more senior positions. Junior researchers may be particularly vulnerable to bias or negative feedback in the open peer review process, which could have a negative impact on their careers.

Additionally, if the reviewers and authors know each other's identities, there is a greater risk of bias and conflicts of interest. For example, a reviewer may be more likely to give a positive review to a colleague or friend, or conversely, may be more critical of a researcher they don't know or don't like.

5. Post-publication review

Post-publication review occurs after an article or research paper has been published. It involves the evaluation of the published work by readers, researchers, or experts in the field, who can then provide feedback.

Post-publication review can take various forms, such as comments on the article published online, social media posts, blogs, or discussion forums. These comments and reviews can be made by anyone who has read the published work, including the general public, researchers, and experts.

Pros: Post-publication review can identify errors or flaws in the published work, provide feedback on the research quality, and stimulate discussion among the research community. The feedback provided in post-publication review can lead to the correction of errors, the refinement of methods, or the development of new research directions.

Post-publication review can also increase transparency and accountability and promote openness and collaboration in the research community. Open discussion and feedback on published research can help ensure that research findings are reliable and trustworthy.

Cons: Unlike standard peer review, which typically includes experts in the related field, post-publication review can be conducted by anyone, regardless of their expertise or qualifications. This can lead to biased or uninformed critiques that are not helpful for improving the quality of the research.

Post-publication review can be subject to the same biases and conflicts of interest that arise in pre-publication peer review. Reviewers may have personal or professional relationships with the author or may be motivated by factors other than the quality of the research.

Finally, post-publication review often lacks consistent standards or guidelines, which can lead to inconsistent or unfair evaluations of research. This can make it difficult for authors to know how to improve their work or for readers to know which reviews to trust.

6. Third-party peer review

In third-party peer review, an independent third party, rather than internal reviewers or academic colleagues, performs the peer review. This type of review is often used in cases where there may be a potential conflict of interest or when a high level of expertise is required.

The reviewers are typically selected by the journal or publisher rather than the authors of the manuscript. The reviewers may be experts in the same or a related field as the authors. Third-party reviewers are either affiliated with academic or research institutions or are independent consultants or professionals.

Pros: Third-party peer review is often used in fields such as engineering, where third-party review is required by regulatory agencies. It is also used in medical fields, where independent review of clinical trials is necessary to ensure patient safety.

Third-party peer review can provide an objective and impartial evaluation of the research or product, which can be important for decision-making purposes. By using an independent third party to provide an objective evaluation, potential bias can be identified and corrected, and the quality of the research can be improved.

Cons: Third-party reviewers may have their own biases or conflicts of interest that could affect their objectivity and the quality of their evaluations.

Additionally, paying for third-party review services can be expensive, particularly for smaller research projects or institutions with limited resources. 

Third-party peer review can also add time to the publication process, which could frustrate \ researchers who want to publish their work as quickly as possible.

Finally, third-party reviewers may not have access to all of the data or information necessary to fully evaluate the research, particularly if the research involves sensitive or confidential information.

7. Transferable peer review

Transferable peer review is when peer reviews of a manuscript are transferred from one journal to another within the same publishing group. This process helps improve the efficiency of the peer review process. It provides a more consistent and high-quality review experience for authors.

In transferable peer review, the author submits their manuscript to a journal within a publishing group or network. If the manuscript is rejected by that journal, the editor may offer to transfer the manuscript and its peer reviews to another journal within the same group or network. The receiving journal then uses the existing peer reviews to guide their decision on whether to accept or reject the manuscript. However, the new journal may commission additional reviews as needed.

Pros: For authors, transferable peer review can save time and effort in the submission process; they don’t have to start the review process from scratch with a new journal. 

It provides a more streamlined and consistent review experience, as the reviews can be transferred along with the manuscript. 

For journals, it can help to reduce the workload of editors and reviewers. Journals can use the work that has already been done by other journals within the same group or network.

Transferable peer review is becoming increasingly common in academic publishing, particularly within large publishing groups or networks. It offers a number of potential benefits for authors, journals, and the broader scientific community.

Cons: There is a possibility the original reviewer's comments and suggestions could be shared with the new journal editor and reviewers and lead to a breach of confidentiality and ethical concerns.

Additionally, if the manuscript is transferred to a journal with a different scope, the reviewers may not have the expertise to evaluate the manuscript appropriately, which could result in a biased or inadequate review.

Finally, some journals may charge additional fees for transferable peer review, which add to the overall cost of publishing the manuscript.

Final thoughts

Peer review is a crucial step in the scientific publishing process. The peer review process is designed to ensure that scientific research meets high standards of quality, rigor, and validity. It provides a means for experts to critically evaluate the work of their peers and help improve the overall quality of scientific knowledge.

However, the peer review process is not without its limitations and criticisms. Nevertheless, peer review remains an essential part of the scientific publishing process. It is widely accepted as a necessary step for ensuring the quality of scientific research.

To see a peer review example, the American Society for Gastrointestinal Endoscopy has a great example from a fictitious study.