Another factor is exposure to violence in the home. For example, Bossarte and Swahn (2008) reported that for African American youth, exposure to violence within the home before the age of ten was associated with a threefold increase in the probability of early initiation of alcohol use. Similar findings were reported by Wallace and colleagues (1999a) for African American youth; these authors also found that the prevalence of alcohol use decreased as a function of how many parents were present in the African American adolescent’s home.