Psychological Safety Framework in Pull-based Open Source Projects
For open-source project maintainers and researchers, this provides a novel, data-driven method to quantify psychological safety and demonstrates its role in contributor retention, though the effect is modest compared to prior participation.
This study introduces a theory-informed framework to measure psychological safety in pull request interactions of open-source projects, operationalized via 10 variables from 60,684 PRs across 26 GitHub repositories. It finds that higher psychological safety is positively associated with both short-term (within 1 year) and long-term (over 4-5 years) sustained participation, though prior participation is a stronger predictor.
Psychological safety refers to the belief that team members can speak up or make mistakes without fear of negative consequences. While it is recognized as important in traditional software teams, its role in open-source software development remains understudied. Open-source contributors often collaborate without formal roles or structures, where interpersonal relationships can significantly influence participation. Code review, a central and collaborative activity in modern software development, offers a valuable context for observing such team interactions. This paper introduces a framework grounded in psychological safety theory to identify behaviors that signal PS in pull request interactions. We operationalize these behaviors using 10 observable variables derived from 60,684 PRs across 26 popular GitHub repositories and construct a PS index at repository level. We then empirically test the relationship between this index and contributors' short-term (within 1 year) and long-term (over 4-5 years) sustained participation using three logistic regression models. Contributors are more likely to remain active in repositories with higher levels of psychological safety. Psychological safety is positively associated with both short-term and long-term sustained participation. However, prior participation emerges as a stronger predictor of future engagement, reducing the effect of psychological safety when accounted for. This study introduces a a theory-informed framework for measuring psychological safety through pull request data and provides empirical evidence of its relevance in sustaining participation within open-source development.