According to an audit of nearly 2.5 million articles published in The Lancet on May 9, 2026, the number of fabricated citations in the biomedical literature has increased twelvefold over the past two years.

An analysis of articles indexed in PubMed found that approximately one in every 277 papers published during the first seven weeks of 2026 cited a paper that does not exist. This marks a sharp increase compared with one in 458 articles in 2025 and one in 2,828 articles in 2023. Researchers led by Maxim Topaz of Columbia University’s Data Science Institute used artificial intelligence to “distinguish genuine fabrications from formatting inconsistencies, such as unofficially abbreviated titles.”

Topaz’s group identified the steepest rise in hallucinated references in mid-2024, which they believe coincided with the rapid development of AI-powered writing tools.

Another high-profile case has interested scientists. Read now