Peak BrAC, reflecting the maximum BrAC value obtained by breathalyzer, served as the primary outcome. Area under the curve (AUC) served as a cumulative index of alcohol exposure. AUC values were based on model-projected aBAC values recorded at 30-second intervals over the session, excluding the priming/waiting period (when the number and timing of drink requests were standardized). AUC values were established with a trapezoidal formula, yielding an index of cumulative brain alcohol exposure in mg% * minutes. Finally, CASE sessions were classified based on whether self-administration resulted in alcohol exposure sufficient to qualify for a heavy episode, defined as achieving BrAC ≥ 80mg% within 2 hours (National Institute on Alcohol Abuse and Alcoholism, 2004). This outcome served as a laboratory analogue of heavy episodic exposure based on a clinically relevant threshold.
