individuals were between the ages of 31 and 65 toward the end of our observation period, which may account for the increases in the 30–49 and 50–64 year age groups. Keyes and Miech (Keyes and Miech, 2013) also found that women born between 1935 and 1949 had high rates of binge drinking, particularly in comparison to women born prior to 1935, for whom rates were very low. NAS data also showed higher binge drinking among women in the 1956–1960 birth cohort relative to the earlier birth cohorts. These cohort effects may have contributed to the increases in binge drinking among the oldest age group and women. It remains to be seen whether period effects or age-period interactions are responsible for the uptick in binge drinking in these groups. In other words, the increase in binge drinking among adults ages 30 and older may stem from birth cohorts with elevated risk for binge drinking with a continued higher risk as they age, or from a normalization of binge drinking among older age groups, or from a combination of these factors.
