How Does Social Frailty Evolve Among Patients with Prostate Cancer? Evidence from Regression Models versus Fuzzy Set Qualitative Comparative Analysis

Background: Social frailty is a critical indicator of declining social functioning and affects quality of life in older adults. Prostate cancer patients face greater challenges in social frailty than the general elderly population, due to the physical burden of the disease, treatment-related adverse effects, and psychological stress. However, its multidimensional influencing factors and risk patterns remain unclear. Objective: To identify key factors and configurations associated with social frailty in patients with prostate cancer. Methods: This study was guided by the Health Ecology Model and used a cross-sectional design. A total of 211 patients were recruited from Shanghai East Hospital between April and September 2025. Structured questionnaires assessed sociodemographic characteristics, family function, living space, depressive symptoms, and social frailty. Data were analyzed using hierarchical regression and fuzzy-set qualitative comparative analysis (fsQCA), enabling the examination of both net effects and complex configurational pathways. Results: