Since the data in Study 1 was focused on the first two weeks of a 12-week medication trial before participants reached the full-dose of the study medication, we chose to assess stress, craving and drinking during the titration phase. As expected, medication condition (Prazosin vs. Placebo) did not significantly affect alcohol use during this period (p>.20) In Study 2, responses collected throughout the entirety of the eight-week behavioral counseling protocol were included in the analyses. To control for any effect of medication condition, we included it as a covariate in the analysis for Study 1. In both studies, we also covaried for the effect of study day or time during treatment on stressful events, craving, and drinking, because it is possible that the behavioral treatment participants received could exert increasing effects as participants attended more sessions. We also controlled for age, gender, psychiatric diagnoses of depression and anxiety, and cigarette smoking status in both studies. We used Multilevel Structural Equation Modeling (MSEM) with Bayesian estimation and fixed slope in Mplus 8.0 to test the prospective mediating effect of craving right
