One of the limitations of our data is the unequal behavioral scores collected to measure alcohol use. Subjects in the CTR group were excluded after screening for alcohol dependence or alcohol abuse, but no information regarding number of drinks or AUDIT score was collected. However, several studies indicate that AUDIT and DSM-IV have similar specificity (Dawson et al., 2012; Foxcroft et al., 2015) providing evidence that subjects in the CTR group were likely assigned to the correct group. A second limitation of the current study is the lack of inclusion of other measures that could have been useful to distinguish among the four sample groups. For example, prior studies (Ahn and Vassileva, 2016; Pariyadath et al., 2014) have used machine learning algorithms to distinguish controls from various substance dependent samples using features from neurocognitive, personality, and psychiatric measures, whereas the current study only used neuroimaging features. Because we relied on a convenience sample combined from existing studies, few measures overlapped, thus preventing us from conducting our analyses with behavioral assessments. Future studies that combine neuroimaging and behavioral assessments will be
