Investigating contributorship and the division of labor in international scientific collaboration

International scientific collaboration has grown substantially, yet little is known about how scientific labor is organized within those. This study investigates the division of labor in international scientific collaboration using the Contributor Roles Taxonomy (CRediT) from articles published in PLOS journals between 2018 and 2024. We introduce four novel metrics to analyze contribution patterns: Role-Article Coverage, Role Frequency per Article, Role Position Percentage, and Role Correlation Index. Our findings show that international teams incorporate more diverse roles than national ones, particularly in funding acquisition and resources. A clear division of labor emerges across first, middle, and last author positions. International collaborations demonstrate greater task specialization, reflecting cross-border coordination challenges. Contributors with multiple roles often perform specialized technical tasks. These findings enhance understanding of global scientific knowledge production and provide insights for research policy and equitable credit allocation in science.