The paper shows that misconduct “has become an industry,” says Anna Abalkina of the Free University of Berlin, who studies corruption in science and was not involved with the research. Richardson and colleagues hope their sweeping case will attract attention and spur change.
They began their analysis by pinpointing corrupt editors. They focused their investigation on PLOS ONE, because the megajournal allows easy access to bulk metadata and publishes the names of the editors who have handled the thousands of papers it publishes each year, making it possible to detect anomalies without behind-the-scenes information. The researchers identified all the papers from the journal that had been retracted or received comments on PubPeer—a website that allows researchers to critique published work—and then identified each paper’s editors.
All told, 33 editors stood out as more frequently handling work that was later retracted or criticized than would be expected by chance. “Some of these were immense outliers,” Richardson says. For instance, of the 79 papers that one editor had handled at PLOS ONE, 49 have been retracted. Flagged editors handled 1.3% of papers published in the journal by 2024, but nearly one-third of all retracted papers.
The team also spotted that these editors worked on certain authors’ papers at a suspiciously high rate. These authors were often editors at PLOS ONE themselves, and they often handled each other’s papers. It’s possible that some editors are being paid bribes, Richardson says, but “also possible that these are informal arrangements that are being made among colleagues.” The researchers detected similarly questionable editor behavior in 10 journals published by Hindawi, an open-access publisher that was shuttered because of rampant paper mill activity after Wiley acquired it. A spokesperson for Wiley told Science the publisher has made “significant investments to address research integrity issues.” (...)
Richardson and his colleagues found that the problem goes far beyond networks of unscrupulous editors and authors scratching each other’s backs. They identified what appear to be coordinated efforts to arrange the publication of batches of dubious papers in multiple journals.
The team looked at more than 2000 papers flagged on PubPeer for containing duplicated images and identified clusters of papers that all shared images. Those sets of papers were often published around the same time and in a limited selection of journals. Looking at patterns of duplicated images is an “absolutely innovative” method for investigating these networks, Abalkina says. “No one has done this before.”
In some cases, the authors suggest, a single paper mill that infiltrated multiple journals may be responsible. But they also believe some of these clusters reflect the work of “brokers” who act as go-betweens, taking papers produced by mills and placing them at compromised journals.
The team dug into the workings of the Academic Research and Development Association (ARDA), based in Chennai, India, which offers services including “thesis/article writing” as well as “journal publication” in a list of dozens of journals. On a web page listing “high impact journals” on offer, ARDA says it liaises with journals on behalf of researchers and “[ensures] they get published successfully in the High Impact Indexing Database journal of their choice.”
Over several years, ARDA’s list of journals has evolved, the team found, with new publications added to the list and others removed after being delisted by bibliometric databases because of fishy behavior. The journals often publish transparently “problematic” articles, Richardson says, and ARDA charges between $250 and $500 for publication, based on quotes offered to Richardson and his colleagues. The website asks authors to submit their own papers, suggesting ARDA itself is not a paper mill, but rather a go-between, Richardson says.
ARDA did not respond to a request for comment.
Organizations like these operate in broad daylight, under the guise of providing “editorial services,” says Lokman Meho, an information scientist at the American University of Beirut. Although their operations may be unethical—with stark consequences for science and scientists—they don’t care about trying to hide, he says, because “it is actually not illegal to run such businesses.”
The problems Richardson and his colleagues documented are growing fast. The team built a list of papers identified in 55 databases of likely paper mill products, looking at the number of suspicious papers published each year between 2016 and 2020. (They excluded the past few years of data because it takes time for fraudulent papers to be discovered and retracted.) They found that the number of suspected paper mill products doubled every 1.5 years—10 times faster than the rate of growth of the literature as a whole, although still a small proportion of papers overall. The number of retractions and papers flagged on PubPeer had also risen fast, doubling every 3.3 and 3.6 years, respectively, but not keeping pace with the increase in suspected fraudulent papers. “This means that the percentage of fraudulent science is growing,” Abalkina says. That poses particular risks to fields like medical science, where the fake papers sometimes make their way into systematic reviews and meta-analyses, potentially distorting our understanding of drugs and treatments, she says.
One contributor is the rapid growth of science, says Wolfgang Kaltenbrunner, a science studies scholar at Leiden University. Paper mill products are often buried in low-impact journals and are written to get little attention, he says. In small scientific communities, it is harder to hide products like these, but as some fields get larger and more anonymous, such papers can escape detection more easily. And as the scientific workforce has burgeoned, institutions have increasingly turned to evaluating scientists based on how many publications they produce, leading some researchers to bolster their records with fake papers, he says. “Perverse incentives, inflated metrics, the ‘publish or perish’ culture, and systemic tolerance for weak scholarship” all allow paper mills to flourish, says Li Tang, an expert on Chinese research policy at Fudan University.
Young researchers may feel forced into paying for paper mill publications to compete with peers—a ratcheting effect that is already apparent, Richardson says. The number of papers published by medical residency applicants has soared in recent years, for instance, with some students claiming authorship of dozens of papers. He says it’s no coincidence that the paper mill industry targets residency applicants, especially foreign students on visas.
Docampo, Abalkina, and others say there’s little in the new paper that wasn’t already strongly suspected. But the dramatic confirmation that the study offers may shift the needle, they say. “We’re massively behind the curve on making visible and realizing the extent of the problem,” Kaltenbrunner says. “The sheer scale of it is the takeaway message here.”
