Social isolation and social media addiction: the serial mediation roles of social anxiety and FoMO among Chinese university students

This study investigates the direct and indirect relationships between social isolation and social media addiction among Chinese university students, with social anxiety and fear of missing out as serial mediators in the digital era. A convenience sample of students from eight universities in China was recruited. A total of 1,000 self report questionnaires were distributed via digital platforms including email, WeChat, and QQ between December 1 and 6, 2025. In total, 732 valid responses were obtained (female 454, male 278). Hypotheses were tested in SPSS and SmartPLS through three stages: (1) descriptive analysis, (2) confirmatory factor analysis, and (3) structural model evaluation. SI is not directly associated with SMA but shows an indirect association with SMA through FoMO, including a significant sequential association via SA and FoMO. SA is not directly associated with SMA and does not function as a simple mediator between SI and SMA. SI is positively associated with SA and FoMO, SA is positively associated with FoMO, and FoMO is positively associated with SMA. By examining potential intra-psychological associations between social isolation and social media addiction, this study advances the compensatory internet use theory and the cognitive activation theory of stress. The findings may contribute to a deeper understanding of this relationship and could guide preventive strategies and educational initiatives that foster healthier engagement with social media among university students.