Patterns of Change over Time in Beliefs Legitimizing Aggression in Adolescents and Young Adults: Risk Trajectories and Their Relationship with Serious Aggression

Using an ecological developmental conceptual framework for understanding and preventing serious aggression, the authors examined the relationship over time between beliefs legitimizing aggression (BLA) and use of aggression. Data from seven waves of the National Youth Survey were used to fit a semiparametric group-based model that identified four distinct trajectories of BLA risk over time: low/stable, moderate/stable, moderate/decreasing, and high/decreasing. Results indicated that BLA risk was associated with the onset of serious aggression by early adolescence. BLA risk status was significantly related to aggression at all seven waves, but the magnitude of the relationships was smaller at later waves. Comparison of the moderate/stable and moderate/decreasing risk groups indicated that decreases in BLA risk level during late adolescence and young adulthood were not related to decreases in levels of aggression. Results suggest that reducing beliefs about aggression is a promising strategy for primary prevention aimed at children and young adolescents but that secondary prevention and treatment should target factors other than BLA risk to bring about reduced levels of aggression. KEY WORDS: adolescents; aggression; beliefs; young adults; trajectories ********** Increases in the level and severity of aggression in youth during the 1980s and 1990s prompted a wealth of research by scholars in social work and other fields aimed at building knowledge of its nature and etiology (Dodge & Pettit, 2003). This research has produced an extensive body of conceptual and empirical literature on the onset and course of serious aggression and related problems in childhood and adolescence and on prevention policies and programs (for example, Crick & Dodge, 1994; Dodge, Dishion, & Lansford, 2006; Fraser & Galinsky, 2004; Hawkins et al., 2003; Metropolitan Area Child Study [MACS] Research Group; 2002). An ecological developmental framework for understanding and preventing aggression and related problems has emerged from this research (Dodge & Pettit). According to the framework, which synthesizes research results from multiple disciplines, serious and chronic aggression is a result of the complex interaction over time of individual and environmental risk factors. Individual-level social--cognitive mechanisms are posited as key risk factors that mediate relationships among more distal factors and the occurrence of aggression. These social--cognitive risk factors often serve as a focus of intervention efforts aimed at preventing and treating serious aggression (U.S. Department of Health and Human Services [HHS], 2001, 2005). The current study examines a particular social--cognitive risk factor, beliefs legitimizing aggression (BLA), and its relationship with serious aggression, There is a focus on examining whether changes over time in beliefs about aggression are related to changes in levels of serious aggression. UNDERSTANDING AND PREVENTING SERIOUS AGGRESSION Multiple Levels of Risk An ecological developmental framework identifies biopsychosocial risk factors that have been empirically linked to serious aggression and related problems (Dodge & Pettit, 2003; see Fraser & Galinsky, 2004, for a more general but similar framework for risk and resilience in childhood). The framework draws on social learning, information-processing, social disorganization, and other theories to postulate processes through which risk factors are thought to influence the onset and course of problems. According to the framework, certain biological and environmental factors predispose some infants to an increased likelihood of early aggressive behavior. Across childhood and adolescence, individual, family, school, peer, neighborhood, and sociocultural risk factors interact, resulting in risk processes that launch some children onto a developmental trajectory characterized by increased and, ultimately, chronic use of aggressive behavior. …