How to peer review manuscripts

If you regularly write manuscripts and submit these to peer-reviewed journals, peer reviewing manuscripts of other researchers is, in my opinion, a moral obligation. Additionally, a good peer review should effectively screen out flawed science. So, peer reviews are important.

I wrote a blog previously on why it is often difficult to find peer reviewers.  This difficulty can result in prolonged delays in the peer review process, and manuscripts are sometimes rejected because no suitable peer reviewers could be found. You would hate it if that were to happen to you.

Once you receive an invitation to peer review, read the abstract, which is usually provided with the invitation, and consider writing the review. Is it within your expertise?  Also, ensure you have no conflict of interest before accepting, such as being a close collaborator. I once even received a request to peer review an article on which I was an author…

After accepting invitations to peer review

The peer reviewer is expected to critically read and evaluate a manuscript in their specialty field, and then provide respectful, constructive, and honest feedback to the authors.

Once you accept an invitation to review a manuscript, here is how to proceed.  Some journals provide clear guidelines on what aspects you need to assess, while others don´t provide guidelines at all. Often, there are at least some aspects that require scoring on a scorecard.

Start by reading the article, and while you are reading, ask yourself some questions and make notes:  

• What is the main question addressed by the research?
• Is the research relevant and interesting?
• Is the topic original? Does it add to the subject area compared with other published material?
• Is the paper well written? Is the text clear and easy to read?
• Are the conclusions consistent with the evidence presented? Do they address the stated objectives?
• If the author disagrees with the current consensus, do they have a case?
• What do the tables or figures add to the paper? Do they aid understanding, and are they clear and concise? Or are they superfluous?

After this initial read-through, you should be able to determine whether the manuscript should be rejected outright or not. Note that even if you think the article should be rejected outright, you need to write a review, so the authors understand why.

Now write a short paragraph on the research question, the goals, approach, and conclusions of the manuscript. The next paragraph should focus on the contribution to the field, whether the methods used are appropriate, and whether the data support the conclusions.

Review to identify major flaws

Next, determine whether there are any major flaws, such as:

• a conclusion that is not based on the evidence presented
• a methodological error
• an inappropriate number of samples/individuals analyzed
• insufficient controls and/or control experiments
• inappropriate sampling (for instance, not the relevant time points)
• statistically non-significant differences presented as significant
• the data in tables or figures are unclear
• insufficient data
• plagiarized text, fraudulent data, or ethical issues => if you suspect any of these, contact the editor without proceeding with the review.

Write down under the heading: ´major problems´ a numbered list of the major flaws, indicating exactly where you found them, what the problem is, and how this may be remedied by the authors (if possible). Be specific in your comments.

Review to identify minor flaws

Reread the manuscript and note down any:

• places where the text is unclear
• errors or invalid arguments

Ask yourself:

• does the title reflect the subject of the paper?
• does the abstract reflect the content of the paper correctly? Are all claims in the conclusion section of the abstract supported by the data?
• is the text overall well written? If not, make a note to the editor so that they can request that a professional editor improve the language.
• if there are only minor typos or mistakes, you may want to indicate these so the authors can correct them

Write down under the heading: ´minor problems´ a numbered list of the minor flaws, indicating exactly where you found them (Section, page numbers, line numbers), what the problem is, and how this may be fixed. Minor flaws include typos and ambiguous text that can be improved.

Comments to the author

Insert here the paragraphs you wrote above, as well as the numbered lists of major and minor flaws.

Do NOT include here your opinion about whether the paper should be rejected, accepted, or revised. Those comments belong in the comments to the editor section.

Comments to the editor

In the comments to the editor, remark on any sections you were unable to assess because they were outside your expertise (for instance, a method or the statistical analyses).

Write down your recommendation (reject, major revision, minor revision, accept) and the reason for this recommendation.

After submitting your peer review, you can add the peer review to your profile in the Web of Science so you can get recognition for your efforts to review manuscripts.