Supplementary file 1_A study on the association between psychological capital and dyadic coping among lung cancer patients and their caregivers: an actor–partner interdependence model approach.docx

Increasing evidence suggests that dyadic coping—the joint process through which patient–caregiver pairs manage illness-related stress—plays a crucial role in emotional adjustment and relationship quality. Meanwhile, psychological capital (PsyCap), comprising optimism, hope, resilience, and self-efficacy, has been recognized as a key positive psychological resource that enhances adaptation to cancer-related challenges.

However, research integrating these two constructs within the lung cancer context remains limited.</p>Methods<p>A cross-sectional study was conducted among 225 lung cancer patient–caregiver dyads recruited from hospitals in Chengdu between January and June 2025. Participants completed the Positive Psychological Capital Questionnaire (PPQ) and the Dyadic Coping Inventory (DCI). Pearson correlation analysis was used to examine bivariate associations, and the Actor–Partner Interdependence Model (APIM) was applied using AMOS 23.0 to explore actor and partner effects between PsyCap and dyadic coping.</p>Results<p>Significant positive correlations were found between patients’ and their caregivers’ PsyCap and dyadic coping (p < 0.01).