Developmental trajectories of perceived friendship intimacy, constructive problem solving, and depression from early to late adolescence.

This study examined friendship types in developmental trajectories of perceived closeness and balanced relatedness. In addition, differences between friendship types in the development of constructive problem solving and depression were examined. Questionnaire data of five annual waves were used from two adolescent cohorts (cohort 1: M = 12.41 years; cohort 2: M = 16.37 years). Growth Mixture Modeling revealed two developmental trajectories in cognitive representations of perceived friendship intimacy: interdependent and disengaged friendships. Adolescents in interdependent friendships were characterized by high perceived closeness and balanced relatedness across adolescence. Furthermore, adolescents in disengaged friendships had lower levels of and smaller increases in constructive problem solving. Girls in disengaged friendships showed smaller increases in balanced relatedness and higher levels of depression than boys in disengaged friendships and adolescents in interdependent friendships.