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Ethical guidelines for peer reviewers

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Ethical guidelines for peer reviewers

Peer review guidelines provide basic principles and standards to which all peer reviewers should adhere during the peer review process in research publication. These guidelines can be applied across disciplines, be a reference for editors and publishers in guiding their reviewers, and an educational resource for institutions for training their students and researchers.

Peer review
Cite this as:
COPE Ethical Guidelines for Peer Reviewers. Version 2 September 2017

© 2020 Committee on Publication Ethics (CC BY-NC-ND 4.0) https://publicationethics.org

COPE guideline

This guideline has advice on

This guideline has advice on how to:

Different types or models of peer review.
Responsibilities of being a reviewer.
How to conduct and write a review.

Key points

Peer reviewers have an important role in ensuring the integrity of the scholarly record, but too often come to the role without any guidance and unaware of their ethical obligations.
Reviewers are expected to provide an unbiased, constructive critique of the manuscript. Reviews should be objective and constructive, ensuring feedback is clear and helpful to authors.
Reviewers should respect the confidentiality of the manuscripts they evaluate. They should not disclose any information about the work or use it for personal advantage, ensuring the integrity of the review process.
Reviewers should declare any potential conflicts of interest. This includes financial, personal relationships, or academic rivalries that could affect impartiality.
Reviewers are encouraged to complete their evaluations promptly to facilitate timely publication processes. Delays can hinder the dissemination of important research findings and affect authors' careers.
The ethical obligations of reviewers, include avoiding bias, respecting intellectual property rights, and recognising the contributions of others. Reviewers must uphold the highest ethical standards in their evaluations.

Guidance preview

Models of peer review

There are different types or models of peer review, all of which have various advantages and disadvantages. It is important to be aware of the model of peer review that the journal or platform uses before agreeing to undertake the peer review.

Being a reviewer

Professional responsibility

Authors who have benefited from the peer review process should consider becoming peer reviewers as a part of their professional responsibilities. Some journals require a formal process of appointment to the review panel, and some require specific expertise; anyone interested in becoming a reviewer should look for the journal guidelines on peer review and follow any requirements posted. 

In order to assign appropriate reviewers, editors must match reviewers with the scope of the content in a manuscript to get the best reviews possible. Potential reviewers should provide journals with personal and professional information that is accurate and a fair representation of their expertise, including verifiable and accurate contact information.

Competing interests

Ensure you declare all potential competing, or conflicting, interests. If you are unsure about a potential competing interest that may prevent you from reviewing, do raise this. If you are currently employed at the same institution as any of the authors or have been recent (eg, within the past 3 years) mentors, mentees, close collaborators or joint grant holders, you should not agree to review. In addition, you should not agree to review a manuscript just to gain sight of it with no intention of submitting a review, or agree to review a manuscript that is very similar to one you have in preparation or under consideration at another journal.

Timeliness

It is courteous to respond to an invitation to peer review within a reasonable time frame, even if you cannot undertake the review. If you feel qualified to judge a particular manuscript, you should agree to review only if you are able to return a review within the proposed or mutually agreed time frame.

Three pages from the guidance showing the cover, a page with an infographic and table, and a back page of further reading and author contributions

Translated versions

  • Spanish: Guías éticas para revisores pares
     

Further information

  • Author contributions

    Conceptualisation: 

    • Irene Hames, on behalf of COPE Council (Version 1).

    Writing – original draft preparation:

    • Irene Hames, on behalf of COPE Council (Version 1).

    Writing – revision draft preparation

    • Elizabeth Moylan and Charon Pierson, on behalf of COPE Council (Version 2)

    Writing – review and editing: 

    • Tara Hoke, Trevor Lane, Elizabeth Moylan and Charon Pierson (Version 2).

    Supervision: 

    • Charon Pierson (Version 2)

    Visualisation:

    • Elizabeth Moylan and Charon Pierson (Version 2)
       

  • Acknowledgements

    We are grateful for the feedback and advice received from Kelly Cobey, John Hilton, Mark Hooper and Irene Hames which shaped the 2017 revision.

  • Further reading

  • Change history

    • Version 2: 2017

      Version 1: 2009

    • 29 February 2024

      Language change to ‘anonymised review’

    • 21 September 2022

      Added redirects from old PDFs to this page

    • 25 November 2020

      Design and branding updated in Version 2 PDF.

    • 1 April 2019

      Added link to Version 1.

    • 2017 

      Version 2 published.

    • 2009

      Version 1 published.

Comments

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Inappropriate comments will be deleted. Please read the COPE Code of Conduct for events and discussions for expected behaviour during events and when participating in online discussions on the COPE website. 

Ehsan A commented 7 July 2025, 11:00 BST

Thank you for this information 

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