An international scientific journal has retracted 107 articles after it discovered irregularities in their peer reviews.

The articles were published in Tumor Biology between 2012 and 2016, and their authors were nearly all Chinese researchers. The journal disclosed the mass retraction on Thursday, saying in a statement that “after a thorough investigation we have strong reason to believe that the peer review process was compromised.”

Tumor Biology’s publisher, Springer, had discovered that the email addresses of peer reviewers — experts in the same field who make sure the paper meets scientific standards — were fake.

“The articles were submitted with reviewer suggestions, which had real researcher names but fabricated email addresses,” Peter Butler, editorial director at Springer for cell biology and biochemistry, told Sixth Tone. “The editors thought the articles were being sent out to genuine reviewers in the discipline. Following our investigation and communication with the real reviewers, they confirmed that they did not do the peer review.”

It is common practice among Chinese reviewers and researchers to use their personal — rather than institutional or academic — email addresses in their communications with scientific journals; consequently, the journals’ editors find these email addresses difficult to trace and verify, putting the peer review process in doubt, according to Zhang Li, greater China senior communications manager with Springer Nature, previously Tumor Biology’s publisher.

One of the retracted articles is authored by Liu Wei and his colleagues in the department of general surgery at Bethune International Peace Hospital in Shijiazhuang, capital of northern China’s Hebei province.

“The journal rejected my paper initially,” Liu told Sixth Tone. “Then I turned to a specialized company that my classmates recommended to have it polished.” After the company’s touch-ups, Tumor Biology accepted the article.

Liu said he was actually happy with the delay, because the journal’s impact factor — an indication of its reputation and credibility — had risen in the meantime. But he added that the retraction will certainly affect him, as the article was his doctoral thesis.

Editorial director Butler said that Springer is aware that many authors entrust their manuscripts to third-party agencies for language editing. However, he said, “It is unclear whether the authors of the manuscripts were aware that the agencies were proposing fabricated reviewer names.”

Last year, Chinese academia witnessed perhaps its most serious allegation of fraud. In May 2016, Chinese scientist Han Chunyu and his team at the relatively unknown Hebei University of Science and Technology published a paper in scientific journal Nature Biotechnology. The scientists said they had made a breakthrough in research on a gene editing technology that could potentially help cure cancer.

But other scientists were unable to recreate their results, and Han was accused of having fabricated his research. In November, the journal issued an “Editorial Expression of Concern,” which is often a step toward a full retraction.

Editor: Kevin Schoenmakers.

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