Using Both the Dimensional and Typological Approaches in Understanding the Relation Between Temperament and Psychopathology: A Twin Study Across Early Development

Although there is extensive research on temperament and its relation to psychopathology, most studies to date have used a dimensional approach to temperament, assessing one or two temperament traits at a time, which does not account for the interrelatedness between temperament dimensions. Recent studies have identified statistical methods that can capture these heterogenous relations that take a more typological approach. The current study used data from a racially/ethnically and socioeconomically diverse sample of twins to investigate whether using these different analytic methods together to capture temperament contribute to the conceptualization of phenotypic and genetic temperamental risk for later cross-reporter factors of anxiety, depression, externalizing, and ADHD. In breaking psychopathology down into its respective components, as measured by multiple reporters, I found that temperamental genetic risk for psychopathology differed depending on the psychopathology factors assessed. In using both dimensional and typological approaches to temperament, I found that high negative emotionality may only act as a risk factor for anxiety and ADHD when children also have low effortful control and high impulsivity. Results also showed an inconsistent role of genetics and the environment that explain the relation between temperament and psychopathology depending on the approach used. Examining typological and dimensional approaches together supported well-known findings and challenged others, highlighting importance of taking multiple approaches in investigating the phenotypic relation between temperament and psychopathology, and its etiology.