Evolution of bilateral and multilateral collaboration of EU-14 countries across disciplines, 2010-2024

Abstract: This study explores the evolution of bilateral and multilateral research collaboration of nine EU-14 member states, both within Europe and globally, across six disciplines, between 2010 and 2024, using OpenAlex data. Results indicate that bilateral collaboration rates remained relatively stable and predominantly concentrated within EU-14 countries, followed by the USA, the UK, and China. Multilateral collaboration rates increased significantly across all disciplines, with the highest increase observed in medicine and the highest overall rates maintained in physics & astronomy. The same trend across disciplines was observed for the Relative Intensity of Collaboration (RIC). This reflects the growing importance of large-scale international research consortia in infrastructure-intensive fields that address global scientific challenges. RIC has increased for both bilateral and multilateral collaboration, with stronger growth in multilateral collaboration. Multilateral RIC fell below the expected level most frequently with South Korea, India, and China. Across both collaboration types, increases in collaboration rates were generally associated with increases in RIC. No substantial changes in collaboration rates or RIC with the UK were observed following Brexit. A decline in multilateral collaboration with Russia in physics and astronomy coincided with its suspension from Horizon Europe in 2022, while the collaboration rate in medicine increased.