Our results are consistent with other literature that has examined trajectories of substance use in longitudinal samples through adulthood. For example, Pampel (2008) observed convergence in race/ethnic rates of smoking from early to mid adulthood in a national longitudinal sample, and a longitudinal sample of high-risk boys in Pittsburgh also demonstrated a later onset and greater persistence among African Americans relative to Whites followed into young adulthood (Finlay et al., 2012; White et al., 2004). These results are also consistent with, and extend, the findings of Chen and Jacobsen in the Add Health sample, who reported that racial/ethnic differences in smoking converge, and cross-over for marijuana use, in young adulthood (Chen & Jacobson, 2012). We note differences between the two analyses, however. We document in the present study that rates of cigarette use and alcohol use, in particular, remain robustly higher in Whites compared with Blacks into young adulthood, controlling rigorously for socio-economic differences through the lifecourse, and document these effects for a wide range of quantity and frequency indicators of use, which are critical in order to understand disparities
