Rumination is a Correlate But Not a Cause of Depressive Symptoms During Adolescence

Data reported in this thesis were used to test the applicability of Response Styles Theory (RST; Nolen-Hoeksema, 1987; 1991) to preadolescent and adolescent populations across three studies. First, this thesis tested whether rumination maintained and exacerbated distress, and second, whether female adolescents ruminated more than male adolescents. In addition, this thesis compared rumination's ability to predict depression and anxiety with other predictors of maladjustment, such as stress, sense of control, and perceptions of false self. Study 1 had two major objectives, first to measure the concurrent relationships among stress, rumination, sense of control and depressive symptoms among 310 preadolescents (9-13 years). Results indicated that 13 year old females were slightly more ruminative and depressed than 13 year old males. Second, rumination mediated rather than moderated the relationship between stress and depressive symptoms. The second objective of Study 1 was to assess peer and parental influences in developing a ruminative response style. It was tested whether preadolescents expect females to ruminate more than males. In addition, parents (N = 218) of these preadolescents reported whether they would encourage female children to ruminate more than male children. Data showed that preadolescents did not expect female preadolescents to ruminate more than male preadolescents, and similarly, parents did not encourage female children to ruminate more than male children. Study 2 also had two objectives: first, to develop and validate a new scale entitled the Perceptions of False Self scale (POFS), enabling an additional predictor of maladjustment to be compared with rumination. This scale was constructed because existing scales (SWIT; Harter & Waters, 1991) are difficult for adolescents to understand and complete. The POFS scale was developed using a multi-method approach, involving 331 adolescents (11-16 years). The POFS scale proved to be reliable and valid, and exhibited a stronger relationship with maladjustment (depression and anxiety) than existing measures. Study 2 also reported the relationships among stress, rumination, sense of control, perceptions of false self, and maladjustment among 195 adolescents across 10 weeks. Rumination predicted increases in later maladjustment when measured in isolation. However when stress, sense of control, and false self were included as predictors, rumination no longer predicted changes in maladjustment. Interestingly, the direction of effect among the measured variables seemed to flow from maladjustment to risk and vulnerability. In Study 3, depressive and anxious symptoms were measured separately to test whether stress, rumination, sense of control, and perceptions of false self exhibited distinct relationships with anxious and depressive symptoms. Data were collected from 926 adolescents (11-17 years) across 4 months. Females were slightly more ruminative than males from age 12, however, females did not report higher maladjustment until age 14. Furthermore, rumination and depression exhibited a bidirectional relationship across 4 months when measured in isolation, however when additional variables were assessed this relationship disappeared. In fact, anxiety, not rumination, predicted increases in maladjustment. In combination, these studies show that although females report more maladjustment than males, this difference is small, supporting a gender similarities rather than a gender differences perspective. Second, rumination does not predict increases in either depressive or anxious symptoms during adolescence. Therefore, these findings challenge the applicability of RST to adolescent samples. It is concluded that rumination is a correlate, not a cause of depressive and anxious symptoms during adolescence.