"Let's embark on a joint health journey" - How Boundary Negotiating Artifacts Influence Patients' Psychological Ownership in Chronic Care

CSCW and HCI research has a standing discourse on boundary negotiating artifacts and psychological ownership. Both concepts are attributed the potential to address the spreading chronic disease pandemic and rising healthcare costs. While CSCW has attended only to boundary negotiating artifacts to study patient-provider collaboration, the psychological ownership discourse primarily focuses on the perception of ownership over digital objects. Despite studies in both discourses reporting promising results, the concepts have been studied separately. Accordingly, the ways boundary negotiating artifacts relate to psychological ownership in healthcare interactions remain unclear. In this research-through-design study, we evaluate the Digital Companion as a technology-based boundary negotiating artifact. Our field study with 27 patients shows how the Digital Companion fosters psychological ownership in weight management by bridging domains and closing the loop between patient self-management and medical support in consultations. By understanding how boundary negotiating artifacts foster psychological ownership, we gain deeper insights into how patients assume and share ownership of their therapy plans. Our analysis uncovers the emergence of perceived shared ownership as BNAs create concordance between patients and physicians.