Trajectories of adolescent friendship stability: Links to internalizing and physical health symptoms

Although the protective effects of high-quality friendships in adolescence are well-established, less is known about how adolescents' friendship stability changes over time and whether adolescents' friendship stability shapes health outcomes. Using six waves of data from 388 adolescents ( M age = 14.05, SD = 0.41; 61% female), the current study examined trajectories of friendship stability across high school and assessed whether friendship stability predicted internalizing and physical health symptoms. Results demonstrated declines in friendship stability throughout high school and indicated that greater average levels of stability, but not linear trajectories of stability, over time predicted better health. Findings suggest that although friendships become increasingly unstable across high school, adolescents with higher overall levels of friendship stability experience better health. • Adolescents' friendship stability declined across high school. • Changes in friendship stability were not associated with later internalizing or physical health symptoms. • Higher overall levels of friendship stability predicted fewer internalizing and physical health symptoms. • Friendship stability may serve as a point of intervention to improve adolescents' overall health.