Nearly 3,000 peer-reviewed biomedical papers contain fabricated references that could not be verified in scientific databases, according to an AI-assisted audit published in The Lancet.
US and European researchers, led by Columbia University’s Associate Professor Maxim Topaz, screened 2.5 million papers published between 1 January 2023 and 18 February 2026 in PubMed Central’s Open Access collection. Among 97.1 million verified references, they identified 4,046 fake citations across 2,810 papers, with the rate growing more than 12-fold since 2023 and rising most sharply from mid-2024, coinciding with the wider use of AI writing tools.
The findings follow a Nature analysis suggesting tens of thousands of 2025 publications might include invalid AI-generated references, while a second Nature report on the Lancet audit said the study found nearly 3,000 biomedical-science papers with fake references.
A/Prof Topaz’s team said fabricated references can be difficult to detect because they may be correctly formatted, topic-specific, attributed to real researchers and given plausible publication dates. The problem could affect patient care if non-existent evidence is incorporated into systematic reviews or clinical guidelines, they said. “This discovery directly impacts patients, as medical professionals make treatment decisions based on clinical guidelines,” said A/Prof Topaz.
In one paper reviewed by the team, 18 of the 30 references were fake, with some already cited by other papers and appearing in systematic reviews that inform clinical care. At the time of the audit, 98.4% of affected papers had received no publisher action.
