CSA frequently occurs in combination with other adverse events or conditions that contribute to psychological problems. CSA is more common in families in which one or both parents have a history of problem drinking (1, 2, 10, 24) or psychopathology (24, 25); children are physically or emotionally abused or neglected (10, 24, 25); and/or familial conflict, including violence between parents or parental separation, occurs (10, 25). Depression (4, 7) and posttraumatic stress disorder (PTSD) (26, 27) are also common among girls who have been sexually abused. Each of these co-occurring conditions is associated with early and problem substance use as well. Parental alcohol problems have been linked to early age at first drink and first cigarette (17, 28) as well as regular smoking (29), and cannabis dependence (30, 31). Exposure to adverse events such as physical abuse has been linked to early use of alcohol (9, 10), cigarettes (12, 13), and cannabis (9, 12), as have both depression (32, 33) and PTSD (8, 21). This clustering of risk factors makes it difficult to determine whether the observed elevation in risk
