Can soil science research dig itself out from a citation stacking scandal?

Jan Willem van Groenigen

Last year, the soil science community was rocked by reports that an editor, Artemi Cerdà, was accused of citation stacking — asking authors to cite particular papers — boosting his profile, and that of journals where he worked. (Cerdà has denied the allegations.) The case had some major fallout: Cerdà resigned from two journals and the editorial board of Geoderma, additional editors resigned from their posts, and a university launched an investigation. In the midst of the mess, a group of early career scientists in the field released an open letter, urging the leaders of the community “to establish a clear road map as to how this crisis will be handled and which actions will be taken to avoid future misconducts.” Today, Jan Willem van Groenigen, Chair of the Editors in Chief of Geoderma, along with other editors at the journal, published a response to those letter-writers — including a list of the 13 papers that added 83 citations the journal has deemed “unwarranted.” The editorial includes a list of “actions we have taken to prevent citation stacking from recurring and to further strengthen the transparency of the review process” — including monitoring editors and showing authors how to report suspicious conduct.

Retraction Watch: It’s been nine months since the young researchers released their open letter — why respond now?

Jan Willem van Groenigen: This is not our first response. We already responded early March 2017 to this case by online publishing a “letter to the Geoderma community” in which we stated that citation stacking had taken place in our journal. We also stated the number of affected articles and the approximate number of unwarranted citations, although we did not provide details on them like we do in our current editorial. We also announced that Prof. Cerda had withdrawn as member of our Editorial Board. I think that, after the [European Geosciences Union] journals who detected and published this misconduct first, we might have been the first journal to respond.

At that time, we thought that our response would suffice – our journal was relatively minorly affected compared to several other journals where prof. Cerda held an editorial position or reviewed more manuscripts. We expected at the time that those journals would take the lead in any follow-up actions, which we could then join. In our view, these actions should have been aimed at (i) correcting the publication record; and (ii) restoring confidence in soil science publication by making clear what measures will be taken to avoid this happening again.

One year later, with the notable exception of the EGU journals, no such action seems to have taken place. We noticed a large degree of frustration [among] especially younger scientists about this case – a feeling that you can apparently “get away with” this type of misconduct. For that reason we decided that we should take additional action. I would like to emphasize that the two aims mentioned above can only be achieved if other journals follow our example – especially those journals who are more strongly affected than we are.

RW: You emphasize that the authors of the papers that added the unwarranted citations “bear no blame” — they agreed to add the citations at the editor’s request, correct? Doesn’t that afford them some responsibility?

JWG: I do indeed not think it is reasonable to hold the authors responsible for this. In all cases, the number of suggested citations by Prof. Cerda was much larger than the citations that ended up in the published paper- if the authors hadn’t refused to accept most of his suggestions then the number of unwarranted citations would have been much larger. The authors were presented with a list of suggested references by Prof. Cerda (as he always signed his reviews, the authors of the Geoderma papers were generally aware of the identity of the reviewer), an authority in his field. Moreover, many of his suggested citations were not to papers by himself but to journals he edited – something which is much less obvious to detect. Single reviews could therefore easily be mistaken by the authors for genuine (over)helpful suggestions by a well-meaning authority in the field.

RW: How can you be sure all of the added citations were unwarranted?

JWG: Because we critically went through all suggested citations again, one of the reasons that it took us a while to respond. There was a general pattern for the reviews which he submitted to our journal: they would generally consist of few if any substantial comments, with “minor revisions” as recommendation. In addition he would often refer to an attached pdf for some apparently minor additional comments. Due to the apparent minor nature of the comments in the pdf, our Editors-in-Chief would generally not study it in detail. In the pdf, his main focus would then be almost exclusively on suggesting additional references in the introduction and discussion sections, accompanied by rather generic suggestions that the authors should put the paper in larger context, or that the references should be more recent. The wording was often remarkably similar between reviews.

I realize that there is a fine line between an over-enthusiastic reviewer suggesting additional references, and real misconduct. However, the recurring pattern in his reviews for us, combined with the fact that he had a direct interest in being cited for the large majority of his suggestions, proves beyond any reasonable doubt that they were suggested only to increase his personal citation record as well as that of the journals he edited – something which is expressly forbidden by the [Committee on Publication Ethics] guidelines.

RW: Cerdà has insisted he only recommended those papers for authors to read/review for background, not to cite. Why do you not believe that explanation?

JWG: Because, at least for our journal, it is not in line with our findings. All his reviews for the papers that were published with unwarranted citations in Geoderma contain sentences clearly suggesting to change the reference list (e.g. “I just suggest some literature update”, “I just wish to suggest to update the reference list“, ”…and “I recommend that you will refresh your references with recent publications”). In these reviews there were few, if any, suggestions to read articles for background information.

RW: Why was it such a difficult choice to release the identities of papers that had included unwarranted citations?

JWG: Because we strongly feel that the authors of the affected papers are not to blame (see point above). In all cases, the authors refused to include a large number of suggested references by Prof. Cerda. Perhaps in an ideal world the authors should have criticized every single suggested reference, but under the conditions I think this would have been unrealistic to expect. I would like to emphasize that we take responsibility as Editors-in-Chief for providing the authors with these reviews. We should have detected the misconduct earlier and have implemented measures to make sure that this does not happen again in the future.

RW: As measures to prevent future incidents, you note that Cerdà will not serve as an editor, author, or reviewer “for the foreseeable future.” In addition, the journal will perform routine checks on editors to ensure they aren’t suggesting an unusual pattern of references, and explicitly let authors know they can report any suspicions they may have. In addition, you note: “We are implementing several technical innovations in our editorial system that make it much easier to detect strange patterns of behaviour by reviewers.” Can you say more about that, and how they work?

Catriona Fennell, director of publishing services at Elsevier: New methods for the detection & prevention of citation manipulation are being investigated in close collaboration between Elsevier and Prof. van Groenigen and colleagues at Wageningen University. It is currently being determined how best to share these methods publicly without giving away so much detail that would allow reviewers to ‘’game’’ and avoid detection. More details will follow later this year.

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2 thoughts on “Can soil science research dig itself out from a citation stacking scandal?”

  1. Sadly, this goes on in various shapes and forms (some more blatant/detectable than others) in many academic fields, including mine. I am glad this is being discussed very seriously, as my impression (from my colleagues in my narrow field) is that “this is how you play the game, so mind your own business, ICC”.

    It is worth reminding those not familiar with a most notorious citation stacking scandal:

    One of those involved in said scandal sued Nature Publishing Group for libel for reporting the latter story in their news section. However, justice prevailed:

  2. There was an interesting report from Wageningen University, that looked at one of the people involved. A short story can be found in the link further down.

    Most interesting to me was the following:
    “On the other hand, she must have noticed the ‘help’ coming from Cerdà and she was definitely guilty of citation pushing in one instance. This does not constitute a violation of scientific integrity, however, as the code of conduct for scientists does not have any rules on reviewing and editorial activities.”

    “The [Dutch Association of Universities] has decided to include rules in the scientific code of conduct for researchers who act as reviewers or editors for scientific journals.”

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