Co‐Rumination as a Moderator Between Best‐Friend Support and Adolescent Psychological Distress

ABSTRACT Introduction Co‐rumination, characterized by excessively discussing problems and dwelling on negative affect within a dyadic friendship, has been associated with adolescents' symptoms of depression, anxiety and perceived stress‐collectively referred to as psychological distress. This study explored whether co‐rumination moderates the association between perceived best friend support and psychological distress. Methods The study included 187 adolescents (52.9% girls; 88.0% Dutch ethnic background) recruited from two cohorts between March 2017 and July 2019. Assessments took place at two time points: symptoms of depression, anxiety, and perceived stress were assessed via self‐report measures at the final grade of primary school (T1; M age = 11.8 years) and in secondary school (T2; M age = 13.3 years). Co‐rumination and perceived best friend support were measured via self‐report in secondary school. Results Findings indicate that best friend support was associated with lower psychological distress and conversely, co‐rumination was associated with higher psychological distress while adjusting for prior distress symptoms. Moderation analysis revealed that moderate levels of co‐rumination (relative to the samples mean) decreased the positive effects of perceived best friend support on symptoms of depression ( B = 0.06, SE = 0.03, 95% CI [0.00, 0.11], p = 0.05, β = 0.11) and perceived stress ( B = 0.06, SE = 0.01, 95% CI [0.03, 0.08], p = 0.000, β = 0.10). At very high levels of co‐rumination (relative to the samples mean), best friend support exacerbates perceived stress. Discussion This study underscores the potential negative impact of co‐rumination in supportive peer relationships and recommends promoting awareness of the risk of co‐rumination while building a repertoire of (dyadic)emotion regulation strategies.