[4] Over 1,000 researchers were excluded from the 2023 list in total, largely for unethical citation practices and other examples of poor academic integrity.
[5] Specifically, researchers affiliated with Saudi Arabian universities saw a sharp decline from the previous years' rankings in 2023.
[6] In April 2023, El País revealed that Saudi universities had been paying researchers to add their institution as an affiliation.
[9] From 2001 to 2016, the percentage of HCRs affiliated with institutions from mainland China increased, reflecting the increased spending on research conducted by Chinese colleges and universities, though during this time, the number of affiliations specifically to the Chinese Academy of Sciences decreased.
[12] (For further information, see: Women in STEM fields and Sexism in academia) As of their 2022 list, Clarivate uses "performance statistics" from data in the Web of Science.