The bidirectional relationship between depression and perceived social support among college freshmen: evidence from longitudinal and daily diary methods

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.