Early conduct problems, including aggression towards people or animals, destruction of property, deceitfulness or theft and serious violations of rules [6], have been associated with various measures of substance use later in life. For instance, White et al. [7] found that higher levels of conduct problems among boys in early adolescence predict higher levels of alcohol and marijuana use from age 13 to 18. In addition, Elkins et al. [8] reported that endorsing conduct symptoms by age 11 predicts initiation of tobacco, alcohol, and illicit drug use, and that a diagnosis of Conduct Disorder (CD) between age 11 and 14 predicts all three types of substance use disorders by age 18. The established association between conduct problems and substance use may be explained by a common aetiology.
