Trends in U.S., past-year marijuana use from 1985 to 2009: An age–period–cohort analysis

摘要: Abstract Background We present a formal age–period–cohort analysis to examine if the recent increase in past-year marijuana use among young is specific younger generation or if, instead, it part of general across cohorts all ages. This first that includes adult trends from 2001 09. Methods Data come National Survey on Drug Use and Health, series annual, nationally representative, cross-sectional surveys U.S. civilian, non-institutionalized population. The focuses 25 year time span 1985 2009 uses recently developed ‘intrinsic estimator’ algorithm estimate independent effects age, period, cohort. Results not unique youngest birth cohorts. An independent, positive influence cohort membership use, net historical period age effects, smaller for today's than was came immediately before, and, fact, at its lowest level three decades. more consistent with effect has acted Period differ substantially Hispanics. Conclusions major forces drive are moving away cohort-specific factors toward broad-based influences affect Strategic public health policy efforts aimed addressing should do same.