Read the manuscript, get back to the journal if anything is not clear and requesting any missing or incomplete items you need. Do not contact the authors directly without the permission of the journal. It is important to understand the scope of the review before commencing (i.e., is a review of raw data expected?).
Confidentiality: Respect the confidentiality of the peer review process and refrain from using information obtained during the peer review process for your own or another’s advantage, or to disadvantage or discredit others. Do not involve anyone else in the review of a manuscript (including early career researchers you are mentoring), without first obtaining permission from the journal (Reviewer asks trainee to review manuscript). The names of any individuals who have helped with the review should be included so that they are associated with the manuscript in the journal’s records and can also receive due recognition for their efforts.
It is important to remain unbiased by considerations related to the nationality, religious or political beliefs, gender or other characteristics of the authors, origins of a manuscript or by commercial considerations. If you discover a competing interest that might prevent you from providing a fair and unbiased review, notify the journal and seek advice (Reviewer requests to be added as an author after publication). While waiting for a response, refrain from looking at the manuscript and associated material in case the request to review is rescinded. Similarly, notify the journal as soon as possible if you find you do not have the necessary expertise to assess the relevant aspects of a manuscript so as not to unduly delay the review process. In the case of doubleblind review, if you suspect the identity of the author(s) notify the journal if this knowledge raises any potential competing or conflict of interest.
If you come across any irregularities with respect to research and publication ethics do let the journal know (Contacting research ethics committees with concerns over studies). For example, you may have concerns that misconduct occurred during either the research or the writing and submission of the manuscript, or you may notice substantial similarity between the manuscript and a concurrent submission to another journal or a published article. In the case of these or any other ethical concerns, contact the editor directly and do not attempt to investigate on your own. It is appropriate to cooperate, in confidence, with the journal, but not to personally investigate further unless the journal asks for additional information or advice.
Publishers may have policies related to transferring peer reviews to other journals in the publisher’s portfolio (sometimes referred to as portable or cascading peer review). Reviewers may be asked to give permission for the transfer of their reviews if that is journal policy. If a manuscript is rejected from one journal and submitted to another, and you are asked to review that same manuscript, you should be prepared to review the manuscript afresh as it may have changed between the two submissions and the journal’s criteria for evaluation and acceptance may be different. In the interests of transparency and efficiency it may be appropriate to provide your original review for the new journal (with permission to do so from the original journal), explaining that you had reviewed the submission previously and noting any changes.
Preparing a report
Follow journals’ instructions for writing and posting the review. If a particular format or scoring rubric is required, use the tools supplied by the journal. Be objective and constructive in your review, providing feedback that will help the authors to improve their manuscript. For example, be specific in your critique, and provide supporting evidence with appropriate references to substantiate general statements, to help editors in their evaluation. Be professional and refrain from being hostile or inflammatory and from making libellous or derogatory personal comments or unfounded accusations (Personal remarks within a post-publication literature forum).
Bear in mind that the editor requires a fair, honest, and unbiased assessment of the strengths and weaknesses of the manuscript. Most journals allow reviewers to provide confidential comments to the editor as well as comments to be read by the authors. The journal may also ask for a recommendation to accept/revise/reject; any recommendation should be congruent with the comments provided in the review. If you have not reviewed the whole manuscript, do indicate which aspects of the manuscript you have assessed. Ensure your comments and recommendations for the editor are consistent with your report for the authors; most feedback should be put in the report that the authors will see. Confidential comments to the editor should not be a place for denigration or false accusation, done in the knowledge that the authors will not see your comments.
Remember it is the authors’ paper, so do not attempt to rewrite it to your own preferred style if it is basically sound and clear; suggestions for changes that improve clarity are, however, important. In addition, be aware of the sensitivities surrounding language issues that are due to the authors writing in a language that is not their first or most proficient language, and phrase the feedback appropriately and with due respect.
It is the job of the peer reviewer to comment on the quality and rigour of the work they receive. If the work is not clear because of missing analyses, the reviewer should comment and explain what additional analyses would clarify the work submitted. It is not the job of the reviewer to extend the work beyond its current scope. Be clear which (if any) suggested additional investigations are essential to support claims made in the manuscript under consideration and which will just strengthen or extend the work.
Prepare the report by yourself, unless you have permission from the journal to involve another person. Refrain from making unfair negative comments or including unjustified criticisms of any competitors’ work that is mentioned in the manuscript. Refrain from suggesting that authors include citations to your (or an associate’s) work merely to increase citation counts or to enhance the visibility of your or your associate’s work; suggestions must be based on valid academic or technological reasons. Do not intentionally prolong the review process, either by delaying the submission of your review or by requesting unnecessary additional information from the journal or author.
If you are the editor handling a manuscript and decide to provide a review of that manuscript yourself (perhaps if another reviewer could not return a report), do this transparently and not under the guise of an anonymous additional reviewer.