{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T17:53:02Z","timestamp":1792086782184,"version":"4.4.0"},"reference-count":61,"publisher":"National Academy of Sciences","issue":"42","license":[{"start":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T00:00:00Z","timestamp":1792022400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000925","name":"DHAC | National Health and Medical Research Council","doi-asserted-by":"publisher","award":["2029249"],"award-info":[{"award-number":["2029249"]}],"id":[{"id":"10.13039\/501100000925","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.pnas.org"],"crossmark-restriction":true},"short-container-title":["Proc. Natl. Acad. Sci. U.S.A."],"published-print":{"date-parts":[[2026,10,20]]},"abstract":"<jats:p>Research and scholarship are shaped by article citations, which underpin the communication of ideas, assignment of credit, journal impact factors, and author career progression. Given their key influence on author and journal metrics, citations can be intentionally manipulated to inflate the reputation of journals and researchers. Paper mills, unethical organizations that produce and sell manuscripts and publishing services, may also be manipulating citations, but the extent of this manipulation is unknown. Here, we show that molecular cancer articles sharing features with retracted papers from paper mills display citation patterns that suggest systematic inflation. These articles were published in journals in the top decile of journal rankings. Suspected paper mill articles received 50 to 100% more citations than other papers 1 to 3 y after publication, while paradoxically attracting fewer readers and online accesses. Suspected paper mill articles also cited\u2014and were cited by\u2014other suspected paper mill articles, which frequently appeared in journals previously reported as paper mill targets. Citations from suspected paper mill articles measurably inflated journal citation metrics. These findings suggest that paper mills inflate the citation metrics of supported publications and affected journals at scale. This widespread manipulation of citation metrics may amplify unreliable findings, slowing scientific progress and spurring unreasonable citation benchmarks for research articles, journals, and authors. Our findings point to measurable signatures of citation manipulation that could support article- and journal-level screening.<\/jats:p>","DOI":"10.1073\/pnas.2618402123","type":"journal-article","created":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T17:37:33Z","timestamp":1792085853000},"update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":0,"title":["Suspected distortion of citations in high-impact cancer journals"],"prefix":"10.1073","volume":"123","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-9036-4973","authenticated-orcid":false,"given":"Baptiste","family":"Scancar","sequence":"first","affiliation":[{"id":[{"id":"https:\/\/ror.org\/01dkyve95","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Statistics and Computer Science, Institut de Recherche Math\u00e9matique de Rennes UMR 6625 CNRS, L\u2019Institut Agro","place":["Rennes, France"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8923-0587","authenticated-orcid":false,"given":"Jennifer A.","family":"Byrne","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/00hwmnh71","id-type":"ROR","asserted-by":"publisher"}],"name":"New South Wales Health Statewide Biobank, New South Wales Health Pathology","place":["Camperdown, Australia"]},{"id":[{"id":"https:\/\/ror.org\/0384j8v12","id-type":"ROR","asserted-by":"publisher"}],"name":"School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney","place":["Camperdown, Australia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6910-9440","authenticated-orcid":false,"given":"David","family":"Causeur","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/01dkyve95","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Statistics and Computer Science, Institut de Recherche Math\u00e9matique de Rennes UMR 6625 CNRS, L\u2019Institut Agro","place":["Rennes, France"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6339-0374","authenticated-orcid":false,"given":"Adrian G.","family":"Barnett","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/03pnv4752","id-type":"ROR","asserted-by":"publisher"}],"name":"School of Public Health and Social Work, Queensland University of Technology","place":["Kelvin Grove, 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