Medvedev, ONWang, GYKrägeloh, CUZhao, Q2025-10-302025-10-302025-10-21Discover Psychology, ISSN: 2731-4537 (Print); 2731-4537 (Online), Springer Science and Business Media LLC, 5(1), 126-. doi: 10.1007/s44202-025-00486-62731-45372731-4537http://hdl.handle.net/10292/20025During transition to adulthood, competitiveness can significantly influence an individual’s success in academic, professional, and social contexts. This study applied the Revised Competitiveness Index (RCI) to a sample of 227 individuals aged 18 to 29, measuring competitiveness across three time intervals, each separated by three weeks, to assess the stability of this trait using generalizability theory. Findings indicate that competitiveness, as measured by the RCI, exhibits significant consistency across time points, underscoring its presence as a stable trait rather than a fluctuating state. The results suggest that competitiveness remains a persistent characteristic within this demographic, potentially aiding in identifying individuals with a natural disposition toward competitive environments. Efforts to delineate state competitiveness through the index items proved less fruitful. This research accentuates the importance of considering competitiveness trait within young adults, with implications for designing educational and professional interventions aimed at recognising and nurturing competitive strengths in youth.Open Access. This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.52 Psychology5201 Applied and Developmental PsychologyCompetitivenessYouthRevised competitiveness indexGeneralizability theoryStateTraitJournal ArticleOpenAccess10.1007/s44202-025-00486-6