A neuroscientist who was stripped of her PhD by Danish officials as part of a case going back a decade has notched her ninth retraction — but it took a while.
In 2010, following questions about her work, Milena Penkowa received a three month suspended sentence for embezzlement, document forgery, and “fabrication of evidence.” A back-and-forth legal case against the researcher followed, with Penkowa initially found guilty of fabricating results in her thesis but winning a partial reprieve on appeal in 2016. As we reported in 2017, the University of Cophenhagen retracted Milena Penkowa’s doctoral degree after concluding that she had falsified documents to support claims that she’d conducted animal experiments that didn’t occur.
At the time, Penkowa had lost six papers to retraction. The latest one involves an article published at the end of 2016, “Bismuth adjuvant ameliorates adverse effects of high-dose chemotherapy in patients with multiple myeloma and malignant lymphoma undergoing autologous stem cell transplantation: a randomised, double-blind, prospective pilot study,” which appeared in Supportive Care in Cancer, a Springer Nature title.
The article drew a letter to the editor in 2018 pointing out statistical flaws, as well as some attention on Twitter in August 2019. Then a year passed, with no movement from the journal — a fact not missed by Peter Hansen, one of the 2019 tweeters, who wrote last month:
The editor, Fred Ashbury, did not respond to our request for comment, so we don’t know why the journal finally decided to act. But according to the notice:
The Editor-in-Chief has retracted this article [1]. Following publication, concerns were raised with respect to data and data analyses present in the article. Some of the concerns were voiced in a Letter to Editor [2] and subsequently further concerns were received by the journal. Upon post-publication review of the raw data provided by the authors, the reviewer was unable to replicate the findings and conclusions of the article. The Editor-in-Chief and the article’s original Handling Editor agreed that the data reported in this article are therefore unreliable and retraction of the article is appropriate.
Penkowa and her co-author, Per Boye Hansen, disputed the decision. Boye Hansen has not responded to a request for comment.
The notice — which the original paper does not yet link — includes a detailed reanalysis of the data in the article. A sampling:
The findings of the reanalysis suggested several discrepancies. For instance, it was stated in the paper that there were 33 male and 17 female patients. However, in the current database, the number of male and female patients were 32 and 19 respectively.
Figure 1 of the paper (Stomatitis in myeloma patients): Upon assessment of stomatitis grade in myeloma patients, there was only a single grade 2 event. Therefore, it was not possible to replicate any of the myeloma outcomes in Figure 1 of the paper, such incidence of grade 2 stomatitis, duration of stomatitis, severity of stomatitis, as well as gender differences. The results could not be replicated because there were not enough events.
Figure 2 of the paper (Febrile Neutropenia in myeloma patients): The independent biostatistician was not able to replicate any of the results in Figure 2 of the paper. As an illustration, it was stated in the paper that the incidence of febrile neutropenia in myeloma patients was 40% and 23% in the placebo and bismuth groups respectively (p = 0.0005). However, the calculated difference from the new data was 33.3% vs. 14.3% (p = 0.25). In addition, there were no significant gender differences in the incidence of FN. The mean days of FN were also numerically difference between the recalculated and original reported results. …
It concludes:
Upon reanalysis of the data provided by Hansen et al., almost all of study findings could not be replicated. Indeed, most of the key study endpoints (stomatitis, infection, diarrhea, febrile neutropenia and cytopenia) were not statistically different between patients randomized to receive bismuth and placebo.
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Slight correction: she was not stripped of her PhD, but of her doctoral degree, which is similar to the German “habilitation”.