The electronic diary (ED) system was implemented on handheld computers (PalmPilot IIIxe; Palm, Inc.) running software designed for this study (invivodata, Inc., Pittsburgh, PA). Participants completed assessments on the ED (1) upon awakening (Morning Report), (2) in response to audible prompts presented at random times during the waking day, approximately 5 times per day (Random Prompts), (3) at the start of each drink episode (Begin Drink Report), and (4) when completing each of the first two drinks of each drinking episode (End Drink Report). Given that the present study seeks to elucidate genetic determinants of subjective response to alcohol, the analyses focused on assessments during the reported drinking episodes (below).
