Abstract
BACKGROUND: Depression significantly impairs adolescent mental health and adaptation, a critical issue for freshmen. Although depression and perceived social support (PSS) are known to be associated, their bidirectional relationship remains poorly understood. METHODS: This study employed a multi-method approach to clarify this relationship. Study 1 was a three-wave longitudinal survey (N = 761) conducted over 3 months to examine trait-level associations. Study 2 utilized a 7-day daily diary method (N = 1,016) to assess state-level dynamics and minimize recall bias. RESULTS: Cross-lagged analyses from the longitudinal study (Study 1) showed a reciprocal relationship: baseline depression predicted lower subsequent PSS, and baseline PSS predicted lower subsequent depression. Converging evidence from the daily diary study (Study 2) confirmed this bidirectional pattern at the daily level: daily state depression predicted lower PSS the next day, and conversely, daily PSS predicted lower state depression the next day. CONCLUSION: Our findings consistently demonstrate the bidirectional relationship between PSS and depressive symptoms across short-term and long-term timeframes. This underscores the importance of addressing both factors simultaneously in interventions aimed at enhancing the psychological adjustment and mental well-being of freshmen.