Leading diabetes researcher acted negligently, probe concludes

Kathrin Maelder
Kathrin Maedler

Several duplications in the work of a prominent diabetes researcher were the result of negligence, but there is not enough evidence to support charges of misconduct, according to an investigation at her university in Germany.

Recently, we’ve reported on several notices for papers co-authored by Kathrin Maedler, a researcher at the University of Bremen. So far, Maedler has one retraction, multiple corrections, and two expressions of concern to her name, after several of her papers were questioned on PubPeer. Previously, the University of Zurich in Switzerland — where Maedler completed her PhD in 2002 — determined there was a lack of evidence to support allegations of misconduct in papers that were part of her doctoral thesis. 

Last week, the University of Bremen released its own investigation report (in German), which we translated using One Hour Translation. It concludes that Maedler

had published duplicate pictures in several cases and had repeatedly failed to exert due diligence in organising her area of study over a long period of time. In addition, she failed to store the original data on durable and secure storage media, which amounts to negligence.

A University of Bremen spokesperson confirmed to us that Maedler is still based at the institution.

There is insufficient evidence to suggest that Maedler was guilty of scientific misconduct, the report notes:

Pursuant to Article 1, Section 1 of the Regulation…the conclusion that Dr. Mädler was guilty of “scientific misconduct” would require proof of “deliberate or grossly negligent misrepresentation.” After weighing all evidence, the members of the Commission unanimously conclude that there is insufficient indication of deliberate or grossly negligent misrepresentation. An external review also concluded that so far, none of the experiments has been refuted in terms of content — on the contrary, additional checks confirmed the results.

Maedler told Retraction Watch that the investigation was a “long, very fair and very transparent process,” adding: 

During the investigations, we did find mistakes and identified their origin, which could have been avoided with a better strict and fully organized laboratory data documentation, saving and presentation strategy. In some cases, I requested repetitions of the experiments-in-question from lab members, who originally were not co-author of the published papers and were not involved in the original experiments- for me to independently show that all data are correct.  All repetitions fully confirmed the published results.

Nevertheless, added Maedler, as the senior author of the papers in question, she takes full responsibility for the mistakes.

She added:

Immediately after we have identified the mistakes in data storage, we have improved our lab data storage, presentation and documentation rules in order to avoid such mistakes in future.

The report also mentions a warning by the institution’s rector, Bernd Scholz-Reiter:

A warning was issued to Dr. Mädler regarding the identified violations of due diligence and she was cautioned that such errors could not be allowed to occur, particularly when publishing the results of research. The Rector’s admonition also obliges Dr. Mädler to draw the attention of the publishers of the journals involved to the duplicate images…

When asked if any more of her papers are due to be retracted, corrected, or flagged with expressions of concern, Maedler said:

During the investigation process I have identified and clarified all mistakes which had occurred and provided all data as well as parallel experiments to the editorial boards of the respective journals.

Maedler has been the recipient of several awards, including the 2012 Paul Ehrlich and Ludwig Darmstaedter Prize for Young Researchers (Germany).

We’ve recently found another corrigendum for a paper in Xenotransplantation, which lists Maedler as the second author. The notice for Expression of Fas but not Fas ligand on fetal pig beta cells,” which was issued in March, notes that two figures were published incorrectly, and corrects the figures and their legends. The 2004 paper has been cited seven times, according to Clarivate Analytics’ Web of Science, formerly part of Thomson Reuters.

We’ve also come across a (paywalled) erratum for the book chapter, “Interleukin-Targeted Therapy for Metabolic Syndrome and Type 2 Diabetes,” which lists Maedler as first author. It was issued after the original paper didn’t mention that the book chapter had been previously published by Informa, but was republished by Springer with Informa’s permission. The book chapter has been cited 12 times.

Like Retraction Watch? Consider making a tax-deductible contribution to support our growth. You can also follow us on Twitter, like us on Facebook, add us to your RSS reader, sign up on our homepage for an emailevery time there’s a new post, or subscribe to our daily digest. Click here to review our Comments Policy. For a sneak peek at what we’re working on, click here.

2 thoughts on “Leading diabetes researcher acted negligently, probe concludes”

  1. “An external review also concluded that so far, none of the experiments has been refuted in terms of content — on the contrary, additional checks confirmed the results.”

    That’s entirely irrelevant to the question of whether misconduct occured.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.