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Scientific authorship: guests, courtesy, contributions, and harms.

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


DrugMonkey asks, where's the harm in adding a "courtesy author" (also known as a "guest author") to the author line of a scientific paper?

I think this question has interesting ethical dimensions, but before we get into those, we need to say a little bit about what's going on with authorship of scientific papers.

I suppose there are possible worlds in which who is responsible for what in a scientific paper might not matter. In the world we live in now, however, it's useful to know who designed the experimental apparatus and got the reaction to work (so you can email that person your questions when you want to set up a similar system), who did the data analysis (so you can share your concerns about the methodology), who made the figures (so you can raise concerns about digital fudging of the images), etc. Part of the reason people put their names on scientific papers is so we know who stands behind the research -- who is willing to stake their reputation on it.


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The other reason people put their names on scientific papers is to claim credit for their hard work and their insights, their contribution to the larger project of scientific knowledge-building. If you made a contribution, the scientific community ought to know about it so they can give you props (and funding, and tenure, and the occasional Nobel Prize).

But, we aren't in a possition to make accurate assignments of credit or responsibility if we have no good information about what an author's actual involvement in the project may have been. We don't know who's really in a position to vouch for the data, or who really did heavy intellectual lifting in bringing the project to fruition. We may understand, literally, the claim, "Joe Schmoe is second author of this paper," but we don't know what that means, exactly.

I should note that there is not one universally recognized authorship standard for all of the Tribe of Science. Rather, different scientific disciplines (and subdisciplines) have different practices as far as what kind of contribution is recognized as worthy of inclusion as an author on a paper, and as far as what the order in which the authors are listed is supposed to communicate about the magnitude of each contribution. In some fields, authors are always listed alphabetically, no matter what they contributed. In others, being first in the list means you made the biggest contribution, followed by the second author (who made the second-biggest contribution), and so forth. It is usually the case that the principal investigator (PI) is identified as the "corresponding author" (i.e., the person to whom questions about the work should be directed), and often (but not always) the PI takes the last slot in the author line. Sometimes this is an acknowledgement that while the PI is the brains of the lab's scientific empire, particular underlings made more immediately important intellectual contributions to the particular piece of research the paper is communicating. But authorship practices can be surprisingly local. Not only do different fields do it differently, but different research groups in the same field -- at the same university -- do it differently. What this means is it's not obvious at all, from the fact that your name appears as one of the authors of a paper, what your contribution to the project was.

There have been attempts to nail down explicit standards for what kinds of contributions should count for authorship, with the ICMJE definition of authorship being one widely cited effort in this direction. Not everyone in the Tribe of Science, or even in the subset of the tribe that publishes in biomedical journals, thinks this definition draws the lines in the right places, but the fact that journal editors grapple with formulating such standards suggests at least the perception that scientists need a clear way to figure out who is responsible for the scientific work in the literature. We can have a discussion about how to make that clearer, but we have to acknowledge that at the present moment, just noting that someone is an author without some definition of what that entails doesn't do the job.

Here's where the issue of "guest authorship" comes up. A "guest author" is someone whose name appears in a scientific paper's author line even though she has not made a contribution that is enough (under whatever set of standards one recognizes for proper authorship) to qualify her as an author of the paper.

A guest is someone who is visiting. She doesn't really live here, but stays because of the courtesy and forebearance of the host. She eats your food, sleeps under your roof, uses your hot water, watches your TV -- in short, she avails herself of the amenities the host provides. She doesn't pay the rent or the water bill, though; that would transform her from a guest to a tenant.

To my way of thinking, a guest author is someone who is "just visiting" the project being written up. Rather than doing the heavy lifting in that project, she is availing herself of the amenities offered by association (in print) with that project, and doing so because of the courtesy and forebearance of the "host" author.

The people who are actually a part of the project will generally be able to recognize the guest author as a "guest" (as opposed to an actual participant). The people receiving the manuscript will not. In other words, the main amenity the guest author partakes in is credit for the labors of the actual participants. Even if all the participants agreed to this (and didn't feel the least bit put out at the free-rider whose "authorship" might be diluting his or her own share of credit), this makes it impossible for those outside the group to determine what the guest author's actual contribution was (or, in this case, was not). Indeed, if people outside the arrangement could tell that the guest author was a free-rider, there wouldn't be any point in guest authorship.

Science strives to be a fact-based enterprise. Truthful communication is essential, and the ability to connect bits of knowledge to the people who contributed is part of how the community does quality control on that knowledge base. Ambiguity about who made the knowledge may lead to ambiguity about what we know. Also, developing too casual a relationship with the truth seems like a dangerous habit for a scientist to get into.

Coming back to DrugMonkey's question about whether courtesy authorship is a problem, it looks to me like maybe we can draw a line between two kinds of "guests," one that contributes nothing at all to the actual design, execution, evaluation, or communication of the research, and one who contributes something here, just less than what the conventions require for proper authorship. If these characters were listed as authors on a paper, I'd be inclined to call the first one a "guest author" and the second a "courtesy author" in an attempt to keep them straight; the cases with which DrugMonkey seems most concerned are the "courtesy authors" in my taxonomy. In actual usage, however, the two labels seem to be more or less interchangeable. Naturally, this makes it harder to distinguish who actually did what -- but it strikes me that this is just the kind of ambiguity people are counting on when they include a "guest author" or "courtesy author" in the first place.

What's the harm?

Consider a case where the PI of a research group insists on giving authorship of a paper to a postdoc who hasn't gotten his experimental system to work at all and is almost out of funding. The PI gives the justification that "He needs some first-author papers or his time here will have been a total waste." As it happens, giving this postdoc authorship bumps the graduate student who did all the experimental work (and the conceptual work, and data analysis, and drafting of the manuscript) out of first author slot -- maybe even off the paper entirely.

There is real harm here, to multiple parties. In this case, someone got robbed of appropriate credit, and the person identified as most responsible for the published work will be a not-very-useful person to contact with deeper questions about the work (since he didn't do any of it or at best participated on the periphery of the project).

Consider another kind of case, where authorship is given to a well-known scientist with a lot of credibility in his field, but who didn't make a significant intellectual contribution to work (at least, not one that rises to the level of meriting authorship under the recognized standards). This is the kind of courtesy authorship that was extended to Gerald Schatten in a 2005 paper in Science another of whose authors was Hwang Woo Suk. This paper had 25 authors listed, with Schatten identified as the senior author. Ultimately, the paper was revealed to be fraudulent, at which point Schatten claimed mostly to have participated in writing the paper in good English -- a contribution recognized as less than what one would expect from an author (especially the senior author).

Here, including Schatten as an author seemed calculated to give the appearance (to the journal editors while considering the manuscript, and to the larger scientific community consuming the published work)that the work was more important and/or credible, because of the big name associated with it. But this would only work because listing that big name in the author line amounts to claiming the big name was actually involved in the work. When the paper fell apart, Schatten swiftly disavowed responsibility -- but such a disavowal was only necessary because of what was communicated by the author line, and I think it's naïve to imagine that this "ambiguity" or "miscommunication" was accidental.

In cases like this, I think it's fair to say courtesy authorship does harm, undermining the baseline of trust in the scientific community. It's hard to engage in efficient knowledge-building with people you think are trying to put one over on you.

The cases where DrugMonkey suggests courtesy authorship might be innocuous strike me as interestingly different. They are cases where someone has actually made a real contribution of some sort to the work, but where that contribution may be judged (under whatever you take to be the accepted standards of your scientific discipline) as not quite rising to the level of authorship. Here, courtesy authorship could be viewed as inflating the value of the actual contribution (by listing the person who made it in the author line, rather than the acknowledgements), or alternatively as challenging where the accepted standards of your discipline draw the line between a contribution that qualifies you as an author and one that does not. For example, DrugMonkey writes:

First, the exclusion of those who "merely" collect data is stupid to me. I'm not going to go into the chapter and verse but in my lab, anyway, there is a LOT of ongoing trouble shooting and refining of the methods in any study. It is very rare that I would have a paper's worth of data generated by my techs or trainees and that they would have zero intellectual contribution. Given this, the asymmetry in the BMJ position is unfair. In essence it permits a lab head to be an author using data which s/he did not collect and maybe could not collect but excludes the technician who didn't happen to contribute to the drafting of the manuscript. That doesn't make sense to me. The paper wouldn't have happened without both of the contributions.

I agree with DrugMonkey that there's often a serious intellectual contribution involved in conducting the experiments, not just in designing them (and that without the data, all we have are interesting hunches, not actual scientific knowledge, to report). Existing authorship standards like those from ICMJE or BMJ can unfairly exclude those who do the experimental labor from authorship by failing to recognize this as an intellectual contribution. Pushing to have these real contributions recognized with appropriate career credit is important. As well, being explicit about who made these contributions to the research being reported in the paper makes it much easier for other scientists following up on the published work (e.g., comparing it to their own results in related experiments, or trying to use some of the techniques described in the paper to set up new experiments) to actually get in touch with the people most likely to be able to answer their questions.

Changing how might weight experimental prowess is given in the career scorekeeping may be an uphill battle, especially when the folks distributing the rewards for the top scores are administrators (focused on the money the people they're scoring can bring to an institution) and PIs (who frequently have more working hours devoted to conception and design of project for their underlings rather than to the intellectual labor of making those projects work, and to writing the proposals that bring in the grant money and the manuscripts that report the happy conclusion of the projects funded by such grants). That doesn't mean it's not a fight worth having.

But, I worry that using courtesy authorship as a way around this unfair setting of the authorship bar actually amounts to avoiding the fight rather than addressing these issues and changing accepted practices.

DrugMonkey also writes:

Assuming that we are not talking about pushing someone else meaningfully* out of deserved credit, where lies the harm even if it is a total gift?

Who is hurt? How are they damaged?

__
*by pushing them off the paper entirely or out of first-author or last-author position. Adding a 7th in the middle of the authorship list doesn't affect jack squat folks.

Here, I wonder: if dropping in a courtesy author as the seventh author of a paper can't hurt, how either can we expect it to help the person to whom this "courtesy" is extended?

Is it the case that no one actually expects that the seventh author made anything like a significant contribution, so no one is being misled in judging the guest in the number seven slot as having made a comparable contribution to the scientist who earned her seventh-author position in another paper? If listing your seventh-author paper on your CV is automatically viewed as not contributing any points in your career scorekeeping, why even list it? And why doesn't it count for anything? Is it because the seventh author never makes a contribution worth career points ... or is it because, for all we know, the seventh author may be a courtesy author, there for other reasons entirely?

If a seventh-author paper is actually meaningless for career credit, wouldn't it be more help to the person to whom you might extend such a "courtesy" if you actually engaged her in the project in such a way that she could make an intellectual contribution recognized as worthy of career credit?

In other words, maybe the real problem with such courtesy authorship is that it gives the appearance of help without actually being helpful.