National Estimates of Marijuana Use and Related Indicators — National Survey on Drug Use and Health, United States, 2002–2014

National- and state-level data can help federal, state, and local public health officials develop targeted prevention activities to reduce youth initiation of marijuana use, prevent marijuana dependence and abuse, and prevent adverse health effects. As state-level laws on medical and recreational marijuana use change, modifications might be needed to national- and state-level surveys and more timely and comprehensive surveillance systems might be necessary to provide these data. Marijuana use in younger age groups is a particular public health concern, and changing the perception of harm risk from smoking marijuana is needed.