Abstract
The mental health issues of medical postgraduate students are increasingly prominent, and it is urgently necessary to explore the stressors and protective factors. This study adopted an integrative approach to examine the moderating role of psychological flexibility in the relationship between multiple types of life stress and mental health. A total of 5819 medical postgraduate students from a medical university and its affiliated hospitals in Beijing were surveyed in a multi-center cross-sectional study. Measures included psychological worry, supervisory relationship, work-life balance, school support, psychological flexibility, and psychological health. The results showed that all four types of stressors were significantly associated with mental health. Psychological worry was positively associated with psychological distress, while the other three variables were negatively associated with it. Psychological flexibility was negatively associated with psychological distress and the relationship between each stressor and psychological health was weaker with higher levels of psychological flexibility. These findings highlight the heterogeneity in the pathways by which different stressors affect psychological health, underscore the critical role of psychological flexibility in coping with internally generated cognitive stress, and provide theoretical and practical implications for psychological interventions among medical postgraduates.