Three decades of collaboration in rheumatology: a comprehensive co-authorship network analysis (1994-2023)

This study investigated the evolution of collaborative research in rheumatology over 3 decades (1994-2023), utilizing co-authorship network analysis to uncover key contributors, structural trends, and global collaboration patterns. The analysis aimed to provide insights into the dynamics of research cooperation and the factors influencing its development.

A total of 31,231 publications on rheumatology, indexed in the Web of Science (WoS) Core Collection, were analyzed. The co-authorship network was constructed using Python (Version 3.10.5) in the PyCharm environment (Version 2022.1.3). Macro-level metrics, including network density, clustering coefficient, components, and average path length, were evaluated alongside micro-level indicators such as degree centrality, closeness centrality, and betweenness centrality to characterize the network's structure and dynamics. Additionally, temporal trends were examined to assess changes in collaboration patterns over time.

The analysis revealed an expansion in publication volume and collaboration over the 3 decades, with persistent fragmentation evidenced by low network density (below 0.0005) and numerous disconnected components. The number of active researchers and institutions participating in collaborations increased significantly, contributing to enhanced regional cooperation. Key researchers, including Nicolino Ruperto, Josef S. Smolen, and Yoshiya Tanaka, emerged as central figures, consistently facilitating knowledge exchange and collaboration. Localized, tight-knit collaboration patterns, indicated by high clustering coefficients, persisted despite limited global integration. These findings suggest that while rheumatology research networks are becoming more inclusive, significant disparities in connectivity across regions remain.

This comprehensive analysis highlights the dual trends of growth and fragmentation in rheumatology research collaboration. While local collaborations thrive, broader integration remains a challenge, underscoring the need for initiatives fostering global connectivity in the research community. Enhancing international collaboration and reducing resource gaps between regions could accelerate advancements in rheumatology research, benefiting both the scientific community and patients worldwide.