Although potentially traumatic events (PTEs) in childhood are established risk factors for substance use disorders in adults,7-12 scant research has examined the associations of childhood PTEs with initiation of substance use in adolescence. To our knowledge, only four previous studies explicitly examined the role of family adversity and maltreatment on substance use in adolescence. Taken together, these studies reported that aspects of family adversity were associated with earlier age of drug and alcohol use initiation,3,7,8,13 heavier alcohol use among boys reporting sexual assault,13 and drinking as a coping behavior.3 However, prior studies have been limited in several ways. First, prior studies have focused exclusively on childhood maltreatment and family dysfunction without examining other forms of trauma exposure,3,7,8,13 even though potentially traumatic events experienced outside the home are strong predictors of mental health and substance use outcomes in adult populations.14-19 Second, these studies have largely relied on the retrospective reports of adults about maltreatment and substance use in childhood and adolescence,3,7,8 which decrease in accuracy with increasing age.20-22 Third, most studies have assessed clinical or convenience samples,7,8,13 limiting the potential to
