Among the COGA sample, the prevalence of current drinking was negatively associated with age, as the literature suggested and the first part of Hypothesis 3 predicted. However, among current drinkers, problematic alcohol involvement, as indexed by weekly risky drinking, alcohol-related symptoms, and treatment, failed to exhibit a clear relationship with follow-up age, contrary to the second part of Hypothesis 3. When additional subjects are included in the future COGA follow-up, this issue will need to be re-examined, as it runs counter to much of the literature. One possible source of discrepancy may lie with the historically alcohol dependent COGA sample, which contrasts with the epidemiological samples presented in Breslow et al. (2017), Vestal et al. (1977), and Grant et al. (2017); the British civil servants examined in Knott et al. (2018); and the Harvard undergraduates and socially disadvantaged adolescents reported by Valiant (2003).
