Evolving scientific collaboration among EU member states, candidate countries and global partners: 2000-2024

This study explores how EU integration, globalisation, and geopolitical disruptions have influenced scientific collaboration among European countries at different stages of EU membership. Specifically, it distinguishes between the EU-14, the EU-13, that joined the EU in 2004 or later, and EU candidate countries. Using Scopus article, the study analyses Relative Intensity of Collaboration (RIC) among EU member state, candidate countries and China, Latin America, the UK, the USA and Russia. Findings indicate increasing integration within European groups and with global partners, yet persistent hierarchical structures remain. EU-14 countries form the core of the network, exhibiting stable and cohesive collaboration, including with the UK despite Brexit. EU-13 countries occupy an intermediate position, showing moderate collaboration with EU-14 but stronger collaboration within their own group, with EU candidate countries and Russia. EU candidate countries demonstrate even weaker integration with EU-14, focusing on intra-group ties and links with EU-13 and Russia. RIC peaks in 2012 and 2018 for EU-13 and EU candidate countries correspond to Horizon 2020 and Horizon Europe cycles, highlighting the role of EU Framework Programmes. Collaboration with Russia increased following 2014 and only marginally declined after 2022. For EU-14, it exceeds collaboration with the USA. Collaboration with China remains limited due to network and cultural constraints, with similar intensity across all three groups. Overall, funding and policy initiatives are critical for stable international collaboration.

💡 Research Summary

This paper provides a comprehensive bibliometric analysis of scientific collaboration patterns involving European Union (EU) member states, EU candidate countries, and major global partners over the period 2000‑2024. Using the Scopus database (via the CWTS in‑house version), the authors compute the Relative Intensity of Collaboration (RIC) for every bilateral pair among three EU groups—EU‑14 (the long‑standing members), EU‑13 (countries that joined in 2004 or later), and EU candidate states (Albania, Bosnia‑Herzegovina, Georgia, Moldova, North Macedonia, Serbia, Turkey, Ukraine)—as well as with five external partners: the United Kingdom, the United States, China, Russia, and Latin America.

RIC is a normalized, asymmetric metric that compares the observed share of co‑authored papers between two countries to the share expected based on each country’s total output. A value of 1.0 denotes collaboration at the expected level; values above 1.0 indicate preferential or stronger‑than‑expected ties, while values below 1.0 signal weaker links.

Key findings:

1. Core‑periphery hierarchy – EU‑14 forms the network core. Their RIC values consistently exceed 1.0, reflecting a dense, stable intra‑core collaboration. Traditional powerhouses (Germany, France, the Netherlands, Sweden) act as hubs. Even after Brexit, the UK remains a strong partner for EU‑14. Notably, EU‑14’s collaboration with the United States is weaker than its internal ties, underscoring the dominance of intra‑European connections.

2. Intermediate bridging role of EU‑13 – EU‑13 occupies a middle tier. Their RIC with EU‑14 averages 0.8‑0.9, indicating modest but significant interaction. Within the EU‑13 cluster (e.g., Poland‑Czech Republic, Hungary‑Slovakia) and with EU candidates, RIC often reaches or exceeds 1.0. Two pronounced peaks in 2012 and 2018 align with the launch of Horizon 2020 and Horizon Europe funding cycles, demonstrating how large EU Framework Programme calls can temporarily boost cross‑group integration.

3. Peripheral position of candidate countries – Candidate states show the lowest RIC with EU‑14 (typically <0.5). Their collaboration concentrates on fellow candidates, EU‑13, and Russia, reflecting geographic, historical, and linguistic proximity.

4. Dynamics with global partners – Russian collaboration surged after the 2014 Crimea annexation and, despite the 2022 invasion, only modestly declined, suggesting a degree of scientific resilience to geopolitical sanctions. Collaboration with China remains low across all EU groups (RIC ≈0.4‑0.6), constrained by network structure and cultural barriers. Ties with Latin America have grown steadily, especially through Spain and Portugal, leveraging shared language and historical links.

5. Policy implications – The timing of RIC peaks demonstrates the pivotal role of EU Framework Programmes in shaping the European research network. Targeted funding can reduce the hierarchical gap between EU‑14, EU‑13, and candidates, but without sustained, goal‑oriented mechanisms the core‑periphery pattern persists. The authors recommend that EU science policy prioritize bridging funds, support joint calls with candidate countries, and develop stable mechanisms for collaboration with strategic non‑EU partners (Russia, China) that are less vulnerable to political shocks.

6. Limitations – The analysis is confined to Scopus‑indexed articles, which under‑represent many Eastern European and candidate‑country journals, potentially biasing RIC estimates. Moreover, the asymmetric nature of RIC may overstate the importance of collaborations involving small output countries.

In sum, the study maps the evolving architecture of European scientific cooperation, highlighting a robust but hierarchical core, a bridging middle layer, and a peripheral candidate cluster, while showing how EU funding programmes and geopolitical events modulate these patterns. The findings provide evidence‑based guidance for policymakers aiming to foster a more inclusive and resilient European research ecosystem.