Mathieson, Lindsay Catherine2012-11-072012-11-072012-08https://hdl.handle.net/11299/138250University of Minnesota Ph.D. dissertation. August 2012. Major: Child Psychology. Advisors:Nicki R. Crick, Adviser & Bonnie Klimes-Dougan. 1 computer file (PDF); viii, 93 pages, appendices A-B.The current study investigated the contributions of relational aggression and victimization to the sex difference in adolescent depressive symptoms. In addition, pubertal development and both rumination and co-rumination were examined as potential contributing factors. A total of 499 sixth, seventh, and eighth grade students and their teachers participated in the current study. Relational aggression and victimization were assessed by teacher-reports, and all other constructs were measured by self-reports. Surprisingly, no sex differences in depressive symptoms were found. Relational aggression was associated with depressive symptoms, but only when rumination about victimization experiences was high. Relational victimization was associated with depressive symptoms, and this association was partially mediated by rumination about victimization experiences. Neither pubertal status nor timing interacted with relational aggression or victimization to predict depressive symptoms. Therefore, rumination about victimization experiences appears to play an important role in the associations between relational aggression and depressive symptoms and between relational victimization and depressive symptoms. The practical implications of these findings are discussed and recommendations are offered for future research.en-USCo-ruminationDepressionPubertyRelational aggressionRelational victimizationRuminationThesis or Dissertation