University investigation finds misconduct by bone researcher with 23 retractions

Hirosaki University

As a bone researcher continues to accrue retractions, an investigation at his former university has found misconduct in more than a dozen papers.

On Nov. 15, Japan’s Hirosaki University announced it had identified fabrication and authorship issues in 13 papers by Yoshihiro Sato, and plagiarism in another.

Sato, a professor at Hirosaki University Medical School from 2000 to 2003, died in January. He was last affiliated with Mitate Hospital. Multiple retractions in recent months have pushed Sato higher up our leaderboard; by our count, he now has 23 retractions and the university said there are likely more to come.

In an item posted to its website, the university said it launched the investigation in March, after a preliminary inquiry ran from Nov. 28, 2016 until Feb. 1. Concerns about Sato’s work have been circulating since 2015. Hirosaki University noted that a statistical analysis of Sato’s work, published November 2016 in Neurology, prompted it to look into the alleged problems; it also said it received an anonymous tip via email on Nov. 11, 2016.

The investigation looked at the involvement of 26 co-authors, but concluded that Sato alone was responsible for the misconduct. A Google translation of the announcement said that Sato’s co-authors were either “not involved in research fraud” or “not in a position to be held responsible for the research contents.”

For the papers that have not yet been retracted, the university said it plans to request that they be retracted. The university announcement does not list the specific papers.

Hirosaki University has not yet replied to our request for comment.

New retractions

In September, we reported on three retractions requested by Sato. Since then, three journals have retracted five more papers that listed Sato as a co-author.

Three papers, published in Bone, were retracted Nov. 14 at Sato’s request. Here’s the notice that accompanied all three:

This article has been retracted at the request of the Corresponding Author, Yoshihiro Sato, and the co-authors have been informed.

Dr. Sato wishes to retract this article on the grounds that it contains fabricated clinical trial data, which he was responsible for producing. In addition, Dr. Sato claims he listed all of the named co-authors without their consent. The co-authors were therefore unaware of the presence of fabricated data in this publication and their participation in the publication. This retraction was initiated by Dr. Sato, and the Editor-in-Chief of Bone was informed by the author directly.

Here are the three papers:

Given that Sato died nearly one year ago, and the notices say he requested the retractions, we asked the journal how long these were in the works; Bone Editor-in-Chief Sundeep Khosla declined to comment further.

The fourth paper, “Low-Dose Vitamin D Prevents Muscular Atrophy and Reduces Falls and Hip Fractures in Women after Stroke: A Randomized Controlled Trial,” published July 27, 2005 in Cerebrovascular Diseases, was retracted Sept. 23 by the journal’s Editor-in-Chief and managing editor. The editors wrote in the notice that the retraction came:

as a result of concerns about data integrity and scientific misconduct which have been brought to our attention. For further information see also

The 2005 paper has been cited 231 times.

The last paper, a meta-analysis co-authored by Sato that included three of his previously retracted studies, was retracted Sept. 21. “Strategy for prevention of hip fractures in patients with Parkinson’s disease,” originally published Sept. 18, 2012 in World Journal of Orthopedics; the journal was not indexed by Clarivate in 2012. Sato’s retractions have previously led to the retraction of meta-analyses by other authors.

The journal’s editors wrote in the notice that Sato’s co-authors agreed to the retraction and that:

The authors declare that at the time the article was written, none-except for Dr. Yoshihiro Sato were aware of the fact that the studies subject to the analysis had been fraudulently conducted.

Last year, an analysis of Sato’s work concluded that 33 randomized clinical trials co-authored by Sato exhibited patterns that suggest systematic problems with the results.

Hat tip: Rolf Degen, MBAuthor of world fluctuation watch

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6 thoughts on “University investigation finds misconduct by bone researcher with 23 retractions”

  1. Very sorry to hear of Prof Sato. Out of respect for his family I suggest such reports of his work are no longer of importance.

    1. I think it is imperative that the scientific record be corrected, irrespective of the circumstances. If this is not done, other researchers will waste their valuable time & scarce research dollars performing studies that will not be possible to replicate, because the initial studies they are based on were fraudulent.

      1. I agree. It’s a pity for the family, but one’s misdeeds often affect innocent people. I’m sure their friends understand that they had nothing to do with the misconduct.

  2. While it is no longer possible to hear Dr. Sato’s explanations or reasoning, the scientific record should, where possible, be corrected for the sake of those that follow in this field.

  3. I don’t understand, Yoshihiro Sato has passed away in January, how can he request to retract his paper on August or November? Is that the President of Hirosaki University, Kei Sato, who request to retract the papers?

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