Additionally, because the current study's population is re-evaluated, we have the unique capacity to determine whether our identified high-risk genotype for early alcohol initiation is linked to young adult AD, as has been reported in previous cross-sectional COGA studies (Dick, Agrawal, et al., 2006; Dick, Bierut, et al., 2006; Edenberg et al., 2004). Because 60% of the current subjects have not yet had a drink, the 2-year follow-up design of this study will allow collection of onset age of multiple alcohol milestones (first drink, first intoxication, onset of regular drinking, onset of first DSM symptom, first DSM diagnosis, etc.) with minimal recollection bias. It will also provide some clarification as called for by Kuntsche et al. (2016) in describing the relationships of early first drink to the progression from low-level drinking to more problematic drinking in young adults. The use of survival analysis techniques will aid the understanding of how milestone progression affects the onset of AD and may help identify more specific prevention applications.
