of C-RA or A-RA. Fifth, our relatively small sample size of Black twins may have restricted our power to significantly detect certain correlations and variance components. For instance, C-RA is associated with a lower likelihood of ever drinking as well as AUD in Blacks (OR = .61–.69) but these estimates do not achieve statistical significance. Nonetheless, we note that this is currently the largest cohort of Black twins available. Finally, as Black females tend to have a later age at onset of AUD,37 they may not have been past the age of vulnerability during the course of the study.
