Ioannidis, J.

Some scientists reach top citation impact in a very short time once they start publishing. The current analysis defined precocious citation impact as rising to become a top-cited scientist within t[&le;]8 years after the first publication year. Ultra-precocious citation impact was defined similarly for t [&le;]5 years. Top-cited authors included those in the top-2% of a previously validated composite citation indicator across 174 subfields of science or in the top-100,000 authors of that composite citation indicator across all science based on Scopus. Annual data between 2017 and 2023 show a strong increase over time, with 469 precocious and 66 ultra-precocious citation impact Scopus author IDs in 2023. In-depth assessment of validated ultra-precocious scientists in 2023, showed significantly higher frequency of less developed country affiliation (71%), clustering in 4 high-risk subfields (Environmental Sciences, Energy, Artificial Intelligence & Image Processing, Mechanical Engineering & Transports) (64%), self-citations for their field above the 95th percentile (31%), being top-cited only when self-citations were included (20%), citations to citing papers ratio for their field above the 95th percentile (15%), extreme publishing behavior (7%), and extreme citation orchestration metric c/h2<2.45 (15%) compared with all top-cited authors (p<0.005 for all signals). The 17 ultra-precocious citation impact authors in the 2017-2020 top-cited lists who had retractions by October 2024 showed on average 4 of these 7 signal indicators at the time they entered the top-cited list. While some authors with precocious citation impact may be stellar scientists, others probably herald massive manipulative or fraudulent behaviors infiltrating the scientific literature.