Electronic Thesis and Dissertation Repository


Doctor of Philosophy




Dr. Lynne Zarbatany


The purpose of this study was to demonstrate that interaction-based peer groups play an important role in adolescents’ identity development. Peer group members’ current identity development and peer group interaction processes were examined as predictors of teens’ later identity exploration and commitment. Participants (n = 1070; 522 girls; Mage = 15.45 years) reported on their identity development and a subset of participants took part in an interactive group decision task within peer triads (n = 258; 86 triads). Task-related interactions were coded for support (openness to opinions) or discouragement (teasing of opinions and controlling behaviours) of group members' individuality. Nineteen to 22 months later, 103 participants from 59 triads completed a second measure of identity development. As expected, hierarchical linear modelling revealed that the most conducive peer groups for teens’ later identity development had members who had yet to secure personal identity commitments and who supported each others’ individuality (high in openness to others’ opinions and low in controlling behaviours). Unexpectedly, opinion-related teasing in groups also related positively to later identity exploration. For adolescents who had yet to engage in identity processes, membership in committed and controlling groups led to greater identity commitment without exploration (i.e., identification with others’ identity choices). These findings provide evidence that interaction-based peer groups may contribute importantly to identity development in mid-adolescence.