The moderating effect of intolerance of uncertainty on the relation between narcissism and aggression

This study examined the moderating role of intolerance of uncertainty (IU) in the association between narcissism (i.e., grandiose, vulnerable, psychopathic) and aggression (i.e., proactive, reactive). The sample consisted of 310 participants, ages 18 to 30. Consistent with previous research, the three dimensions of narcissism were associated with both functions of aggression. Additionally, IU significantly moderated the relations of vulnerable and psychopathic narcissism with proactive aggression such that the highest aggression was endorsed among participants with high levels of narcissism and IU. The same pattern was evident for self-reported IU in social situations when overall IU was controlled. These findings indicate that IU can affect the relation between narcissism and proactive aggression.