The severity of childhood trauma, e.g. assessed using a continuous severity score, may be a better predictor of negative outcomes than dichotomous measures that simply report presence or absence. Severity of emotional abuse has been associated with greater risk for relapse in cocaine dependent adults (Hyman et al., 2008), while severity of sexual abuse has been associated with a number of outcomes, including increased severity of symptoms in depression and posttraumatic stress disorder (PTSD) (Gamble et al., 2006; Glover et al., 2010). In some cases, relationships between childhood abuse severity and the outcomes of interest are “mediated” by a third factor, i.e., the relationship between predictor and outcome is partially accounted for by the relationships between the mediator and both predictor and outcome (Preacher and Hayes, 2008). For example, neuroticism has been found to mediate the relationship between sexual abuse severity and depression (Gamble et al., 2006). Given the reported association between alcohol-related problems and neuroticism, we hypothesize that neuroticism may play a similar mediating role between childhood trauma exposure and alcohol dependence severity.
