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…

Since the mid-1960s, when illicit drug use burgeoned in the normal youth population, substance use by American young people has proven to be a rapidly changing phenomenon. Smoking, drinking, and illicit drug use are leading causes of morbidity and mortality, both during adolescence as well as later in life. How vigorously the nation responds to…

Conducted as part of the Monitoring the Future project, this study used a cohort-sequential design to examine period, age, and cohort effects on substance use among American youth between the ages of 18 and 28 from the high school classes of 1976 to 1986. This manuscript supersedes Paper 14 in the series which reported on American youth from 18-24…

In 1974, 1979, and 1986, college students completed questionnaires regarding their sexual philosophies, behavior, relationships, self-perceived attractiveness, relationship with parents, use of drugs and alcohol, attitudes toward marriage and abortion, and other issues. Found that sexual behavior increased dramatically from 1974 to 1979, and then…