Analysis reveals fraudulent ‘paper mill’ activity across over 4,000 cancer research articles

An analysis of 33,159 cancer journal articles revealed tell-tale patterns of fake citation numbers across 4,000 articles by ‘research paper mills’, or fraudulent research organisations.

The suspect papers received 50-100 per cent more citations than other articles within one to three years of publication, yet had fewer readers and were accessed less often online, findings published in the journal Proceedings of the National Academy of Sciences.

Researchers said suspect papers tended to cluster in a subset of journals including ‘Journal of Experimental and Clinical Cancer Research’ and ‘Molecular Cancer’ whereas other journals were only marginally affected.

They said ‘research paper mills’, the fraudulent organisations that make money by offering to list people’s names on fake research papers, may also be manipulating citation counts — a key measure of academic performance.

Artificially inflated citation counts distort the evidence base to misinform future research and clinical translation, the team said.

“Just as likes and shares indicate social media influencers’ audience engagement, citations from other researchers are an important academic measure for evaluating scientists’ research impact,” author and statistician Adrian Barnett, from Queensland University of Technology’s Australian Centre for Health Services Innovation, explained.

“Because citation counts are now a key measure of academic performance, they can incentivise journals and researchers to maximise citations counts,” Barnett said.

The author said the researchers documented a pattern that suggested widespread, coordinated manipulation of citation counts by paper mills.

“Artificially high citation rates can inflate journal impact factors, amplify unreliable findings, and slow scientific progress,” Barnett said.

The team evaluated the impact of paper mills on citation patterns in 33,159 articles published in 20 journals between 2012 and 2023.

“Applying our previously developed detection model, we flagged a total of 4,085 articles as potentially associated with paper mills, based on their textual similarity to the titles and abstracts of retracted paper mill articles,” co-researcher Baptiste Scancar said.

Papers flagged by the model had many more citations, compared to non-flagged papers, but had fewer readers, the researchers said.

“Having more citations but fewer readers makes no sense, as citations come from readers,” Scancar said.

“Flagged papers mostly cite and are cited by other flagged papers, measurably inflating the citation metrics of some cancer research journals,” the co-researcher said.

“Flagged papers tended to cluster in a subset of journals including Journal of Experimental & Clinical Cancer Research and Molecular Cancer whereas other journals were only marginally affected,” Scancar said.

Our results support the screening of articles and journals for the patterns of citation manipulation we have described, the researchers said.

“Across leading cancer journals, clusters of interconnected papers bearing the hallmarks of paper mill products accumulate far more citations than other papers despite having fewer readers,” the authors wrote.

“This study provides evidence that citation manipulation leaves measurable traces in citation patterns, offering a practical basis for future screening and intervention,” they said.