The CWTS Leiden Ranking 2025 - More open, more inclusive, more informative

The release of the CWTS Leiden Ranking 2025 marks a next step toward more open and more inclusive research analytics for universities. This post highlights the most significant developments.

Nees Jan van Eck, Rodrigo Costas, Mark Neijssel, Ed Noyons, Martijn Visser and Ludo Waltman • October 29, 2025

Balancing opportunity and risk: rethinking China Scholarship Council programmes amid geopolitical tensions

Amid international concerns over the China Scholarship Council (CSC), especially regarding academic freedom and sensitive knowledge transfer, our study analyses CSC-funded research (2009–2021) to reveal key trends, collaborations, and broader implications.

Qianqian Xie and Alfredo Yegros • October 23, 2025

Crossref as a source of open bibliographic metadata for preprints

Crossref is a crucial source of open bibliographic metadata for articles published in scientific journals. Importantly, however, Crossref can also serve as a source of bibliographic metadata for preprints. In this post, Van Eck and Waltman analyze the completeness of Crossref’s preprint metadata.

Nees Jan van Eck and Ludo Waltman • October 16, 2025

Why AI transparency is not enough

Recently, a taxonomy to disclose the use of generative AI (genAI) in research outputs was presented as an approach that creates transparency and thereby supports responsible genAI use. In this post we argue that such an approach conceals fundamental ethical considerations around research integrity.

Andrea Reyes Elizondo and Peter Tarras • October 15, 2025 • 1 comment

GAIDeT: a practical taxonomy for declaring AI use in research and publishing

Transparency of AI use in academia matters for authors, editors, reviewers, readers and repository moderators. This blog post introduces GAIDeT, a taxonomy for the structured disclosure of Generative AI (GAI) use in research and how it builds trust without adding any extra burden to stakeholders.

Serhii Nazarovets, Natalia Tsybuliak, Jaime A. Teixeira da Silva and Yana Suchikova • August 25, 2025

Academic publishing – stuck in a prisoner’s dilemma?

Facing pressures to stay competitive, researchers publish ever more, often at the cost of quality. Our author shows how this strategic trap can be compared to a prisoner’s dilemma, explains how this situation is exacerbated by predatory journals, and outlines possible solutions.

Sagartirtha Chakraborty • August 14, 2025 • 4 comments

Making bibliometric reporting more transparent and consistent: Participants needed for pilot testing of GLOBAL

The team behind the GLOBAL reporting guideline invites researchers who are preparing or reviewing a bibliometric article to take part in a pilot test of the guideline.

Jeremy Y. Ng, Dimity Stephen, David Moher, Ludo Waltman and Stefanie Haustein • August 12, 2025

Analysing research funding flows in the Global South

In a context marked by deep asymmetries in access to research resources, the research project “Tracking Research Funding Flows in the Global South” aims to make visible and analyze the ways in which international funding for science circulates.

Matías Alcántara, Mariángela Nápoli, Judith Naidorf, Rodrigo Costas and Ismael Rafols • July 22, 2025

Beyond the dissertation: Reshaping PhD trajectories at Leiden University

Open Science and the reform of research assessment are increasingly growing together. Time to also rethink the evaluation of PhD candidates! Talking to six PhD candidates, the authors found that PhD paths need to be more flexible and recognise the diverse activities PhD researchers are active in.

Tanya Lee and Ana Parrón Cabañero • May 27, 2025 • 1 comment

The withdrawal of the US from UNESCO: What does this mean for Open Science?