One obvious consideration is that CASE bears no resemblance to a naturalistic drinking episode. In addition to using intravenous delivery, no efforts are made to incorporate naturalistic cues or contingencies for self-administration—instead, efforts are made to eliminate these contingencies. This approach serves to isolate pharmacological effects to the extent possible, presumably bringing pharmacodynamic effects into clearer resolution. In this context, a relatively lower degree of external validity is intentional and acceptable. Intravenous paradigms are particularly well suited for studies concerned with manipulating pharmacological parameters (e.g., dose or exposure level, rate of aBAC change, blood alcohol limb). Alternatively, studies placing lower priority on these questions might opt for oral procedures, especially given the added cost and resources required for intravenous procedures.
