Longitudinal studies provide developmental science with invaluable information about how variables and the associations between variables change across time, but typically give limited attention to the length of time over which that change occurs. The present study re-analyzed data from previously published meta-analyses of longitudinal data…

The current study demonstrates the application of an analytic approach for incorporating multiple time trends in order to examine the impact of cohort effects on individual trajectories of eight drugs of abuse. Parallel analysis of two independent, longitudinal studies of high-risk youth that span ages 10 to 40 across 23 birth cohorts between 1968…