Finally, personality-depression relations may be multivariate, rather than bivariate, with multiple traits interacting to influence depression. Indeed, in their influential model of personality and depression, Clark & Watson (1999, Clark et al. 1994) hypothesized that depression is characterized by high N/NE and low E/PE, raising the possibility that it is the combination of the two traits that is particularly important in depressive disorders. A growing number of studies have reported that the interaction of high N/NE and low E/PE predicts subsequent depressive symptoms or disorders in adults and youth (Gershuny & Sher 1998, Joiner & Lonigan 2000, Wetter & Hankin 2009), although several studies have not found such an interaction (Jorm et al. 2000, Kendler et al. 2006, Verstraeten et al. 2009). The interaction between N/NE and conscientiousness is also of interest, as the latter construct includes aspects of self-regulation and effortful control (Rothbart & Bates 2006) and may therefore reflect the ability to modulate one’s affective reactivity. Indeed, there is cross-sectional evidence that effortful control moderates the association between N/NE and depressive symptoms in adolescents (Verstraeten et al. 2009).
