When you submit a manuscript to a journal, you write a cover letter to the editor. Your cover letter should say more than just “Here’s a manuscript, please consider it, thanks!” It should have one-paragraph, non-technical summary of your work (at least less technical than your abstract), explaining why it’s interesting/important/novel/etc. and why it’s a good fit for the journal to which you’re submitting it. That encourages the journal to send your ms out for review, which leading journals are increasingly reluctant to do these days. And you usually have to include various legalistic statements, for instance stating that the work reported in the ms was conducted according to all applicable laws and treaties.
This post isn’t about any of that, it’s about another aspect of a good cover letter, one that’s often omitted: suggestions for referees (and, sometimes, requests that certain referees be excluded).
Speaking as a former handling editor, I can tell you that editors typically welcome suggestions for referees. It’s difficult to get people to agree to referee these days, especially for papers outside the area of the editor’s greatest expertise (because in such cases the editor often doesn’t know who is likely to agree to do the review and to do a good job). So your suggestions are welcome. They’re just that, of course–suggestions. The editor may ignore some or all of them. But by all means make suggestions.
When suggesting referees, it’s best to list a few names (say, 3-4), with email addresses, and to briefly explain why you think the people you’ve suggested would be good referees. I often use phrasing like “The following international leaders in the field are among those with the expertise on [topic of the ms] and/or [study system or approach used in the ms] needed to review the ms:…” That phrasing signals a few things to the handling editor. It signals that you’re suggesting the best people, not just your buddies (not that you need shy away from suggesting people you know, even people you know well; just knowing someone isn’t a conflict of interest). It also signals that you think your ms is good, and believe it will stand up to scrutiny by the best people. And in explaining the reasons for your suggestions, you’re helping to guide the editor’s choice of referees. Even if the editor doesn’t use your suggested referees, he or she hopefully will choose others with similar expertise. For instance, I’ve use this phrasing to try to encourage editors to send my protist microcosm papers to others who’ve worked in that system. Such referees not only have the specialist expertise to evaluate every technical detail of my methods, they’re less likely than other referees to misunderstand my ms (and serious misunderstandings do happen sometimes). Finally, you’re signalling your understanding of the audience for the paper, and the readership of the journal. As an editor at Oikos (a general ecology journal), I occasionally handled papers on some specific organism or system, where all the suggested referees were narrow specialists on that organism or system, who (when I looked at their websites) turned out never to have published any general ecology papers. For me, that was a signal (one among others, of course) that the paper wasn’t really a good fit for Oikos. An author who thinks of their paper as an ecology paper, aimed at an ecological audience, ordinarily will suggest referees who are ecologists.
When suggesting referees, if there’s someone who you strongly suspect won’t agree to do the review, don’t bother suggesting their name. For instance, you may not want to bother suggesting extremely famous (and therefore busy) people who you don’t know, unless your paper really is right up their alley or you have some other reason to believe they’ll agree to do it. As another example, I’ve discovered through my experience as an editor that certain people never agree to do reviews. I don’t bother to suggest their names when submitting my own papers.
Hopefully this goes without saying, but when suggesting names, don’t try to pull a fast one and suggest anyone with whom you have a conflict of interest (e.g., someone you’ve co-authored a paper with recently; check the rules for the journal you’re submitting to). And you wouldn’t ordinarily suggest someone who’s already seen a draft of the ms and given you feedback. Anyone who’s done that should be listed in the Acknowledgments, of course.
When should you suggest that certain individuals not be asked to review your ms? In my view, requests to exclude referees should be phrased carefully. One unfortunate side effect of online ms handling systems, I suspect, is that they will erode this care. Many journals now have fill-in-the-blank online forms where you can name preferred and non-preferred referees. The ability to just plug names into a form will, I suspect, encourage authors to suggest referee exclusions without saying why, and so will encourage authors to suggest exclusions on grounds that would not stand up to scrutiny. My advice: don’t give in to the temptation to just fill in the online “non-preferred referees” form with the names of anyone who you think might not like your ms. Sure, use the online form–but explain your reasoning in the cover letter.
What are legitimate reasons for suggesting that someone be excluded? A conflict of interest is the most obvious and clear-cut. If there’s someone who might be asked to review your paper, but who would have to decline if asked due to a conflict of interest, reveal the conflict so that the editor doesn’t bother asking that person for a review. The exception is that you don’t need to bother listing names of people who work at the same place you do. That is a conflict of interest, but it’s obvious enough that it probably doesn’t need mentioning; no competent editor would ever ask for a review from your co-workers.
Conversely, it is not legitimate to suggest excluding someone just because you think they won’t like your ms. Further, it’s a bad idea to try. If you say in your cover letter, “I don’t want Dr. So-and-so to review my paper because I don’t think he’ll like it,” or words to that effect, the implication is that you don’t think Dr. So-and-so is competent to judge your paper, or that he won’t be fair. After all, if Dr. So-and-so is competent and fair, and he doesn’t like it, well, that’s the considered judgment of a competent, fair colleague. Obtaining such judgments is the whole point of peer review! You think Dr. So-and-so might not like your paper? Well, from the point of view of the editor, maybe that’s because your paper has problems! (In which case, perhaps you should’ve phrased your request as “I don’t want Dr. So-and-so to review my paper because I’m afraid he’ll spot the problems with it.”)
And note that saying something like “I suggest excluding Dr. So-and-so because he has previously reviewed my ms” will not fly. The fact that someone has reviewed your ms previously does not disqualify them from reviewing it again. If an editor rejects your ms based on the review of Dr. So-and-so, and then a second editor at another journal decides she also wants a review from Dr. So-and-so, sorry, that’s life. If you’ve revised the ms so as to address Dr. So-and-so’s objections, you’ll be fine. If you haven’t, well, Dr. So-and-so’s review probably will still be negative, but that doesn’t make it wrong. Remember, it’s the editor who makes the decision on the ms, not the referees; their role is merely to give the editor advice. When you resubmit a rejected ms to another journal, it gets handled by a different editor. If that editor, like the first one, also wants a review from Dr. So-and-so, and like the first editor finds that negative review compelling, you have no grounds to complain (assuming of course that the editors in question aren’t just mindlessly “counting the votes” of the referees, which good editors shouldn’t do).
Plus, are you so sure Dr. So-and-so won’t like your ms? I was once asked for a review by an editor who was having trouble finding referees for the paper, and so asked me even though the authors had asked that I be excluded. I actually liked the paper! I don’t know why the authors asked for me to be excluded, although I have a pretty good guess. But the point is, this is one more reason why you shouldn’t try to exclude referees just because you’re worried they might not like your paper.
Of course, if you want to exclude Dr. So-and-so because you don’t think he’ll like your ms, you could try just asking for him to be excluded, without specifying a reason. But as a handling editor, that always made me suspicious. If anything, it made me more inclined to ask Dr. So-and-so for a review.
So if you’re afraid that Dr. So-and-so won’t like your ms, well, sorry, but there’s nothing you can do about that and you probably shouldn’t try, unless there’s some other, legitimate reason to request that Dr. So-and-so be excluded. So, are there such reasons, besides conflicts of interest? I think there are, but it’s a grey area, so don’t take what follows as gospel.
One reason is that the person has some fundamental objection to all work of a certain sort. For instance, I once requested that someone not be asked to review an ms of mine using the Price equation, because this person has published a paper dismissing the Price equation as trivial. I explained in my cover letter that many papers had found the Price equation a valuable approach, and that my paper’s goal was to present a specific, novel application of the Price equation rather than to debate its value in general. That is, I asked for my paper to be judged on its own merits, not by virtue of some controversial criterion totally independent of its specific content. Similarly, I’ve occasionally asked that individuals who’ve written papers making blanket objections to all microcosm experiments not be asked to review my microcosm experiments. As I say, this is something of a grey area; there may well be some valid fundamental reason why all work using some particular approach is fundamentally flawed. And if there is, it’s perfectly legit for the editor to ask for reviews from people who will point out those fundamental flaws. But unless there’s widespread agreement that your approach is fundamentally flawed (in which case, what are you going to do, ask that everyone in the world be excluded from reviewing your ms?), then I think this sort of request is legitimate. The editor might of course ignore your request, but it’s fine to ask. Just to be on the safe side, whenever I request that someone be excluded for this sort of reason, I make sure that my suggested referees are all broad-minded people without a dog in whatever larger fight I’m trying to steer clear of.
A related case is when you have a paper that is tangentially related to, but not really about, some controversial topic, and you don’t want your paper to get caught in the “crossfire”. In such cases, I think it’s fine in the cover letter to explain this, and to ask for referees on both sides of the not-really-relevant controversy to be excluded.
I admit, I’m having trouble coming up with other good reasons why you might ask for someone to be excluded as a referee. In ecology and evolutionary biology it’s hardly ever the case that two labs are racing one another to be the first to complete the exact same study, thereby giving each a strong incentive to review the other’s work negatively. So it’s hard for me to imagine any ecologist or evolutionary biologist citing that sort of thing as a reason to exclude someone. Can anyone think of any other legitimate reasons to ask that someone be excluded from refereeing a ms, besides those already listed?
How much does all this matter, in the sense of affecting the fate of your ms? I don’t know, in all honesty. Probably not all that much, compared to all the other things that affect the fate of your ms. But every little helps.
All this is just my two cents of course; others may have different advice (which hopefully they’ll share in the comments!)
p.s. All of this advice assumes you’re submitting to a selective journal. If you’re submitting to a non-selective journal that only evaluate mss for technical soundness, you can probably just suggest anyone who has the appropriate technical expertise, who doesn’t have a conflict of interest, and who isn’t especially likely to decline a request to review the ms.
p.p.s. I’m sure one reaction to this post is going to be to bemoan the fact that any of this could matter. That the fact I’m posting on this at all just shows the subjective nature of the whole peer review system. To which I’d respond, good luck developing a system for evaluating and communicating science that involves humans but is purely “objective”…