Peer review

Peer review plays a vital role in ensuring the integrity of the scientific record. At the Lancet journals, external peer review only takes place once a paper has been scrutinised internally by our editors (find out more about the journey of a paper).

Selection of peer reviewers

If a paper is sent out for external peer review, editors identify and invite independent experts with relevant scientific or clinical expertise from around the world to review the paper, ensuring their complementary knowledge and skills provide a thorough review of the manuscript. Editors send papers to reviewers with different expertise and from different locations, deliberately seeking reviews that provide an in-depth critique. All research articles are also sent to a statistical specialist, and when relevant other experts such as modellers, data scientists, health economists, or patients with lived experience.

Reviewer comments

Reviewers are invited to provide written comments for authors and confidential comments to editors. Comments are collected, presented, and discussed by the journalâ€?s editors, who make a decision to either reject the manuscript, offer submission to another Lancet family or Elsevier journal,  or invite a revision. The revised paper, along with the authors responses to the reviewers’ points, is again discussed by editors, who may also ask for further comments from (usually the same) reviewers. Once the manuscript is adequately revised and a paper is provisionally accepted, the peer review process is not over. The paper is then passed to a scientifically qualified assistant editor who edits the paper for readability, while continuing to check for consistency and errors. Papers can be rejected at any point.

We are committed to delivering an efficient peer review process. If a manuscript is rejected after peer review, comments will be shared with the authors for them to improve their manuscript and submit elsewhere. If the paper is passed to another Lancet journal, peer review comments will be automatically transferred.

Strengths and limitations of peer review

Peer review is the first stage of a discussion among scientists as to whether the methods of the study support the conclusions made. Critical evaluation of the paper by external peers helps add clarity and acknowledge and report uncertainties and limitations, place new work in the context of the totality of available evidence and prevent over-interpretation.

Peer review does not replicate or validate research. The process relies on trust—peer reviewers are asked to provide a written evaluation of the paper, ask questions of the authors or request clarifications, and then advise editors on whether, based on what is presented to them, it is acceptable for publication, could be acceptable after revision or should be rejected.

The Lancet journals follow best practice guidance on peer review from the Recommendations for the Conduct, Reporting, Editing, and Publication of Scholarly Work in Medical Journals issued by the International Committee of Medical Journal Editors (ICMJE) and support the Committee on Publication Ethics (COPE) ethical guidelines for peer reviewers. Our editors are members of the ICMJE and COPE.

Peer reviewers: by agreeing to review a paper, peer reviewers get early access to world-class research in their fields. Our reviewers take their responsibility as advisors very seriously, and as authors, they themselves are often on the receiving end of peer review. Reviewers are asked to declare any financial, and non-financial academic or intellectual conflicts that might have the potential to influence their critique

Authors: At the Lancet, research papers undergo “single blind” peer review—meaning that the reviewers’ identity is not shared with the authors, unless reviewers chose to sign their reviews. Authors welcome peer reviewer comments as an opportunity to strengthen their manuscript ahead of publication.

Authors share their work with editors on the principle of confidentiality and the expectation that editors and peer reviewers will not circulate the manuscript outside of the peer review process. Outside of the peer review process, authors are encouraged to share their pre-publication findings with relevant health bodies, regulatory agencies, and on preprint servers.

Editors: Authors may disagree with peer reviewers, or peer reviewers may provide conflicting comments. It is the role of editors to negotiate this process. Ultimately, the decision to publish or reject a manuscript is the responsibility of the editor.

The Lancet journals are committed to improving equity, diversity, and inclusion in research and publishing. The Lancet Diversity Pledge expresses our commitment to increasing the representation of women, people of colour, and colleagues from low-income and middle-income countries among our editorial advisers, peer reviewers, and authors.

Several of our journals report on gender and geographical diversity of peer reviewers, including The Lancet and The Lancet Global Health.

Strengthening the training, standards, and expectations around peer review is an important goal for all in the scientific community. The Lancet journals are supportive of any robust research that aims to analyse or strengthen peer review. Please contact the relevant editors should you wish to discuss a project.

At The Lancet, we offer guidance for new peer reviewers, and a small honorarium for fast-track reviews and statistical reviews. We encourage senior reviewers to engage junior colleagues in the review process and our peer review forms include details of any colleagues that have contributed to the review. Each year, the Lancet journals publish the names of all peer reviewers who have contributed to the success of the journal, in recognition of the work they have done.