Structure of externalizing psychopathology

Externalizing disorders are those characterized by a general tendency toward disinhibition and risky, impulsive behaviors that can elicit high costs to individuals and families affected by these problems, as well as to society as a whole (Krueger & Marko, 2006). Discrete difficulties associated with externalizing psychopathology include substance use disorders and antisocial behavior disorders. These problems have been demonstrated to share behavioral tendencies and genetically-based personality characteristics (Krueger et al., 2002). To better differentiate these dysfunctions, Krueger and colleagues (2007) developed a bifactor model describing both the shared disposition for tendencies toward externalizing behaviors, as well as the distinct factors that contribute uniquely to specific manifestations of the externalizing liability. While this model holds great promise as a framework of externalizing psychopathology that accounts for shared and unique variance among discrete disorders, it has only been replicated once for consistency across samples in a study that had some limitations due to item content (Seldom, 2017). As such, the current study investigated whether this model was again most optimal in another sample when using the measurement scale devised by Krueger and colleagues, as well as whether the model remained the best model of risk when other measures of externalizing psychopathology were used. Confirmatory factor analyses were used to compare the single factor and bifactor models in a previously collected undergraduate dataset, both when measured with the Externalizing Spectrum Inventory and when using alternative measures of externalizing psychopathology. Results supported that the bifactor model was the more optimal model of risk for these difficulties, but some issues with fit were still present for the model. These results suggest that further research is needed to determine the construct validity of the bifactor model of externalizing dysfunction. These results help guide research in the genetic, behavioral, and cognitive correlates of these risk factors to further understanding of support and treatment methods for individuals with these difficulties.Department of Psychological ScienceThesis (M.A.