"In conclusion, our study of self-reported marijuana use by adolescents in states with a medical marijuana policy compared with a sample of geographically similar states without a policy does not demonstrate increases in marijuana use among high school students that may be attributed to the policies."

Source

Choo, Esther K. et al., "The Impact of State Medical Marijuana Legislation on Adolescent Marijuana Use," Journal of Adolescent Health, August 2014, Volume 55, Issue 2, p. 160 - 166.
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