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Authorships Research Papers

Conventions of Scientific Authorship

By Vijaysree Venkatraman

Pardis Sabeti published her first scientific paper when she was an undergraduate at the Massachusetts Institute of Technology. Her name had appeared in acknowledgment sections before, but that was the first time she was listed as an author—and she was first on the author list. It was an important milestone in the development of her scientific career.

Sabeti has moved on. These days, as assistant professor in genomics and systems biology at Harvard University, she usually is listed last on papers that come out of her lab. Although students have to earn their way onto the lab's papers, Sabeti admits to being instinctively inclusive when it comes to authorship. Inclusiveness is appropriate, she says, because her students "are always intellectually involved—not just a pair of hands in the lab."

If scientists want to convey this information by the way their names are ordered, the method is similar to sending smoke signals, in code, on a dark, windy night.

—Drummond Rennie

In another lab on the same campus, Stephen Kosslyn, a professor of psychology, employs a more elaborate and specific strategy for assigning authorship. Fifteen years ago, a dispute between a postdoc and a graduate student alerted Kosslyn to the contentiousness of some authorship decisions. Once he explained his rationale to his disgruntled junior colleagues, they agreed that his decision made sense. He decided to spell out his system for future collaborators.

Kosslyn employs a points system, which is explicated on his lab website. Anyone who works with him on a project that results in a paper can earn up to 1000 points, based on the extent of their contribution to six different phases of the project: idea, design, implementation, conducting the experiment, data analysis, and writing. The first and last phases—idea and writing—get the most weight. Those who make a certain cutoff are granted authorship, and their score determines their order on the list. Those who earn less than 100 points are acknowledged in a footnote. "It's very, very rare that there's any sort of issue," he says.

Authors galore

Outside of Kosslyn's lab, the apportionment of credit in an author list—typically the prerogative of the lab head—is rarely straightforward. Although most decisions are uncontroversial, inexplicable omissions and unjustified exclusions are commonplace. Everyone in the scientific community knows stories of authors who shouldn't have been, and non-authors who should have been, Sabeti says.

Science historian Mario Biagioli, the co-editor of the anthology Scientific Authorship: Credit and Intellectual Property in Science, says author attribution has always been a tricky issue. He mentions Robert Boyle, the 17th century chemist whose anonymous employees emerged from the shadows only when he blamed them for things that went wrong, such as explosions. Biagioli says that Boyle's leaving his employees names off his papers wasn't violating any ethical rules, because authorship protocols hadn’t stabilized yet.

Today, reputable journals in every scientific discipline have guidelines for authorship, but the protocols still haven't exactly stabilized, and they rarely address author order. (An exception is high-energy particle physics, where the names of authors—frequently a cast of hundreds—are listed alphabetically.) Authors are free to negotiate their position in the author list with their co-authors, says Sonja Krane, managing editor of the Journal of the American Chemical Society, in an e-mail.

That order matters greatly for scientists in academia, especially scientists who aren't yet established in independent careers. Publication records weigh heavily in hiring, funding, and promotion decisions, and departments, hiring managers, and personnel committees want to know how, and how much, a candidate contributed to a collaborative project. Often, all they have to go on is their position in the author list.

"In the score-keeping that scientists do, first author is the most coveted slot," says Janet Stemwedel, who teaches ethics in science at San José State University in California and writes the Adventures in Ethics and Science blog. Primary authorship is highly valued because it usually indicates who had the idea, who was the "main mover" in the work, or both, Kosslyn says. And because of the way work gets cited (e.g., "First Author, et al., 2010") the first author's name is the most visible to readers. Sometimes more than one author can be "first," indicated by an asterisk or other typographical symbol and an explanatory note. But the person listed first is always the most visible.

With credit comes responsibility: Who is to blame if something's wrong? Typically—but not always—the author listed last is the head of the lab that hosted most of the research. Ideally, this senior author has inspected all the original data analyzed and reported in a paper, notes Randy Schekman, editor-in-chief of the Proceedings of the National Academy of Sciences (PNAS). Consequently, the last author often gets the most grief if things go wrong—and much of the credit when things go right. "The proverbial buck stops there," Schekman says.

Having one person ultimately responsible for everything in a paper is a fine idea. Yet, in collaborative projects involving diverse disciplines and institutions, it's unrealistic to expect one person to be able to vouch for every piece of experimental data, says Bruce Alberts, editor-in-chief of Science, the parent publication of Science Careers. Some journals now require a senior author from each lab to review all of the data generated by their labs and its interpretation. The result is that in complex projects, there can be more than one "last author" just as there can be more than one "first" author; this, too, is usually indicated with typographic symbols and explanatory footnotes.

In addition, almost every scientific article specifies at least one "corresponding author," indicated by a typographic mark and a footnote. The corresponding author is the point of contact for editors, readers, and outside researchers who have questions about the contents of the paper. Often, the corresponding author is also the last author, but she or he may be listed first or even in the middle of the author list.

Gift authorship

For a student who has been left off an author list, it can be especially maddening to see someone included who obviously doesn't deserve it. Also called "honorary," or "guest," authors, gift authors don't make a significant contribution (or sometimes any contribution at all) to the paper, Stemwedel says. Motivations for gift authorship vary; the principal investigator (PI) may think he's doing the recipient a favor, or she or he may think that adding the name of a well-known scientist will improve the odds of getting published in a top journal. Gift authors can appear anywhere on the author list, but usually they're listed in the middle.

Gift authorship is especially damaging when the recipient is a senior author, says Drummond Rennie, deputy editor of the Journal of the American Medical Association (JAMA). Anyone who doesn't realize that the authorship is honorary—that is, almost everyone who reads the paper—will wrongly assume that this well-known scientist has performed his or her role in ensuring the integrity of the data. "Sadly, the paper which had so many fathers till then—as indicated by the author list—suddenly becomes an orphan," Rennie says. Sometimes authorships are even "gifted" without the recipient's knowledge.

Contributor, not author

As collaborations become interdisciplinary and author lists grow longer, who did what becomes even less discernible to readers. "If scientists want to convey this information by the way their names are ordered, the method is similar to sending smoke signals, in code, on a dark, windy night," Rennie says. An unpublished 1995 survey conducted by AAAS—the publisher of Science and Science Careers—found that even editors of clinical journals couldn't agree on the meaning of author order. In a culture that requires precise communication, the traditional means of communicating author's contributions is "scarcely scientific," Rennie says.

So in 1996, Rennie proposed a solution: Each manuscript should contain a clear description of each author's contribution. The team should identify a leader to reassure readers and editors that someone is accountable. Because they describe their roles in print for all to see, the authors can't change their stories later. Top medical journals such as JAMA, The Lancet, British Medical Journal, and Radiology adopted Rennie's proposal.

From an accountability standpoint, the JAMA system would seem to have few disadvantages; Biagioli says the move from "author" to "contributor" has been by far the most innovative step toward transparency in publishing research results. There can be no ethical argument against such explicit authorship, Stemwedel of San José State agrees. Yet the built-in ambiguity of the present system might hold appeal for some, depending where they are in the power structure. For instance, if the last author is a big name, readers could easily assume that the senior scientist provided the intellectual firepower, even if the first author did the heavy lifting, Stemwedel says. Furthermore, agreeing who came up with which fraction of a big idea can be difficult, she adds.

Meanwhile ...

The shift toward a more explicit listing of authorial roles seems likely to continue, but the situation may never completely clarify. Authorship conventions may forever remain specific to the ecologies of particular disciplines, Biagioli says. Schekman adds that journals may never standardize authorship conventions. New entrants to the world of research likely will continue to grapple with the ambiguities of the current system, negotiating for an appropriate spot on the author list.

"Working out relative importance of each person's contribution to the research will still be a judgment call," Stemwedel says. Documenting each author's contribution to the project is good practice, even if a journal doesn't require it, Biagioli advises. A bit of introspection can make the process go more smoothly, says Stemwedel, so "don't wait to for a manuscript to be drafted. At the very beginning of the project, sit down with the members of the team and the PI to discuss which part you plan to take responsibility for." "Revisit this idea at periodic intervals," Biagioli says, so that no one will be surprised to find themselves left off the list, or listed in the middle on a project that they once thought of as theirs.


More from Careers

Stephen Kosslyn first started to consider how author lists come together when he found himself mediating a dispute. A postdoc and a graduate student each wanted to be listed as the first author on a study. “They both had a case,” recalls Kosslyn. “It got heated.”

Disagreements often happen when contributors put in similar amounts of effort on different aspects of a project, says Kosslyn, a psychologist at Stanford University in California. For example, one person might have developed the idea for the project and the other performed most of the data analysis. “The force of the dispute usually revolves around the feeling that whatever they did was more important than what the other person did,” says Kosslyn.

Such disputes are common. “As authorship is our academic currency, it tends to be a hot-button topic,” says Karen Peterson, scientific ombudsman at the Fred Hutchinson Cancer Research Center in Seattle, Washington. She says that one-fifth of the disputes she adjudicates concern authorship. Similar conflicts are among the most common issues mediated by the Committee on Publication Ethics (COPE), says Virginia Barbour, the organization's chairwoman and chief editor of PLoS Medicine in Cambridge, UK.

Authorship disagreements can be mitigated with careful discussions, explicit lab guidelines and a good understanding of authorship practices in one's field. There is no perfect approach, but deciding on who gets an authorship credit, and how they are ranked, is a crucial part of doing science responsibly.

Precise statistics on authorship disputes are hard to come by, says Mario Biagioli, a science historian at the University of California, Davis, who has studied authorship. Scientists may be reluctant to admit that they have demanded undeserved authorship or otherwise subverted the system, and the US Office of Research Integrity does not track such disagreements because they are not considered scientific misconduct, says Biagioli, who co-edited the book Scientific Authorship: Credit and Intellectual Property in Science (Routledge, 2002). However, in a 2005 survey1 of researchers who had received a grant from the US National Institutes of Health (NIH), 10% of respondents admitted to assigning authorship “inappropriately”.

Credit confusion

Questions of who deserves credit for a paper are a fairly recent phenomenon, says Biagioli. Once upon a time, a paper had one author, maybe two. But with modern big science and large collaborations, a study might have hundreds or even thousands of authors — as in the case of the ATLAS experiment2 at the Large Hadron Collider at CERN, Europe's particle-physics laboratory near Geneva, Switzerland.

And what authorship means varies by scientific discipline. For example, in particle physics, hundreds of researchers may contribute to the development and maintenance of a single piece of equipment, such as an accelerator. At big physics labs such as CERN, everyone who was working at the lab when the discovery was made gets a slot on the author list — even if they haven't seen the paper, says Biagioli. The authors are usually listed alphabetically, regardless of how much they contributed.

In the biological sciences, by contrast, the author list is often strictly ranked. The top spot is at the end of the list, where the principal investigator gets credit for running the lab. The student or postdoc who actually did the work goes first. As for the authors in the middle, it is hard to tell whether they participated a lot or a little, says Biagioli.

The International Committee of Medical Journal Editors (ICMJE), headquartered in Philadelphia, Pennsylvania, has developed authorship guidelines that are used by many journals and institutions. These rules state that to be listed as an author, each researcher must meet three key criteria: they must have been involved in designing the project, collecting data or analysing the results; they must have participated in drafting or revising the manuscript; and they must have approved the final, published paper. Many universities that have their own guidelines base them on the ICMJE's wording, says Biagioli.

Kosslyn has his own definition: the crucial element, he says, is creativity. For example, a researcher could work with study participants in the lab, but just be following a protocol. “Anybody could have run the subjects, so running the subjects is not enough,” says Kosslyn. To earn authorship, the researcher would be intellectually engaged: they might point out a feature of the data that leads the team to reshape the experiment. The paper wouldn't look the same without them.

The author in question

COPE recommends that researchers decide who will be an author and what order they will be listed in before they even conduct experiments, and that the group revisits the author list as a project evolves. A handshake isn't enough to seal the deal — researchers should keep author agreements in writing.

Whenever they occur, authorship discussions need not be confrontational (see 'Aggravation-free authorship'). Mark Groudine, deputy director of the Hutchinson Center, says that the parties in a dispute should sit down and try to talk the matter over. “People get so locked into their positions that they don't make the effort to understand the other person's point of view,” he says, “and therefore they don't understand why it's a dispute.”

If talking doesn't work, Groudine suggests asking the opinion of an unbiased third party. For example, on one project he collaborated with another principal investigator. When it came to writing up the paper, both wanted to be senior author. They invited two trusted colleagues to mediate.

The jury awarded the senior slot to Groudine, but he felt uneasy about it. He suggested that the other investigator be the corresponding author, who communicates with the journal and any scientists who enquire about the work. “I consider corresponding author as equivalent, almost, to senior author,” says Groudine. Co-senior authorship is also an option, he adds.

But sharing credit too broadly can be risky. Sometimes authors are listed more as a courtesy than because they made a key contribution, says Chris Sneden, an astronomer at the University of Texas at Austin, who will step down from his post as editor of The Astrophysical Journal Letters at the end of this year. Accepting courtesy authorship is a “double-edged sword”, he says. If the paper becomes famous, “every author gets to claim credit”. But if it becomes infamous, everyone gets a share of the blame. Researchers need to be aware of the potential risks of adding their names to manuscripts that they know little about (see 'Ghosts and guests').

Gerald Schatten, a stem-cell researcher at the University of Pittsburgh in Pennsylvania, learned that lesson when he lent his good name to a high-profile but eventually discredited stem-cell paper by Woo Suk Hwang, then at Seoul National University. Schatten was investigated by his university, which cleared him of misconduct, but chastised him for 'research misbehaviour' because he failed to check the quality of the science3.

The decision to accept courtesy authorship is a matter of preference, says Sneden. “Personally, if I haven't actually contributed something to the specific paper, I just won't have my name on it,” he says. In that case, he politely tells his colleagues that he shouldn't be on the list. “I make sure they understand that it's not a negative reflection on the paper,” he says.

Taken in vain

Sometimes, the recipient of this courtesy may not get the chance to bow out. A researcher who has been added to the author list without their permission might be surprised to see their name when the paper comes out, says Sneden, or even angry if they don't agree with the conclusions. Those who find themselves unexpectedly an author on a paper that they would prefer not to be associated with should contact the editor of the journal, he recommends. The editor will get in touch with the study's corresponding author, and decide whether a corrigendum is necessary to explain that the author in question was not involved with the work.

These kinds of conflicts shouldn't occur. Corresponding authors are expected to have the approval of their co-authors — but some don't realize it. “People, do you read the publication agreement that you sign?” Sneden asks his colleagues. (Often, the answer is no.)

Increasingly, journals are attempting to keep authors in line by asking for details on who did what. In cases of fraud, those descriptions should lay the blame at the right person's door.

Biagioli agrees that delineating each person's contribution should help, but he says that the descriptions are frequently too brief. As an example, he cites the study published this month in Nature by the ENCODE Project Consortium4. It ascribes generic tasks such as “data analysis”, “writing” or “scientific management” to large sets of authors, making it impossible to tell, for example, who analysed which data. When scientists sit down to plan a project — and ideally draft the author list — they should also decide how to describe everyone's contributions, says Biagioli. The relevant details will probably vary by discipline, he adds.

In his own lab, Kosslyn has instituted a scheme to make authorship requirements explicit from the outset. As he listened to his student and postdoc arguing their cases several years ago, he started to develop what eventually became a 1,000-point system. The researchers who come up with the idea get 250 points, split between them according to their contribution; writing the paper is worth the same. A further 500 points are available for designing and running the experiment and analysing the data. Researchers who score at least 100 points make the author list, with each person's point total determining their rank.

Disagreements still occur; in those cases, Kosslyn decides how the points are allocated. When the balance of contributions is unclear, he does his best. However, it rarely comes to tallying points. “Usually it's very obvious what the order's going to be,” he says.

In recent years, no disputes have ever risen to the level of the argument that led to the point system. “That,” says Kosslyn, “was the last heated dispute we had in the lab.”


Bud Abbott and Lou Costello made disagreements about order in baseball the stuff of comedy legend.


Ombudsman Karen Peterson says that one-fifth of the disputes she handles are about authorship.