The Development of Aggression During Adolescence: Sex Differences in Trajectories of Physical and Social Aggression Among Youth in Rural Areas

Few studies have examined the development of social aggression over time or described trajectories of aggressive behaviors for youth living in rural areas. We compared the timing and patterns of physical and social aggression and examined sex differences in development using five waves of in-school surveys administered over 2.5 years. The sample (N=5151) was 50.0% female, 52.1% white and 38.2% African-American. At baseline the average age was 13.1 years. Multilevel growth curve models showed that physical and social aggression followed curvilinear trajectories from ages 11 to 18, with increases in each type of aggression followed by subsequent declines. Physical aggression peaked around age 15; social aggression peaked around age 14. Boys consistently perpetrated more physical aggression than girls, but the trajectories were parallel. Girls and boys perpetrated the same amount of social aggression at all ages. We discuss implications for prevention programming to address the marked increases in both types of aggression observed during early adolescence