Study: Medical marijuana does not increase use among youth

The legalization of medical marijuana in Rhode Island in 2006 did not increase its use among teenagers, according to research presented at the American Public Health Association Annual Meeting and Exposition on Wednesday.

The study was led by Rhode Island Hospital physician Esther Choo.

The finding directly contradicts White House drug czar Gil Kerlikowske's claim that medical marijuana was to blame for the increase in marijuana use among teenagers.

"If young people don't really perceive that [marijuana] is dangerous or of any concern, it usually means there'll be an uptick in the number of kids who are using. And sure enough, in 2009, that's exactly what we did see," Kerlikowske told ABC News Radio last year.

"We have been telling young people, particularly for the past couple years, that marijuana is medicine. So it shouldn't be a great surprise to us that young people are now misperceiving the dangers or the risks around marijuana."

The study was based on an analysis of 32,570 students from Rhode Island and neighboring Massachusetts using a self-report survey called the Youth Risk Behavioral Surveillance System. The study included surveys completed between 1997 and 2009.

The use of medical marijuana has been legalized in 16 states and the District of Columbia, but not Massachusetts.

By comparing the trends in adolescent marijuana use between Rhode Island and Massachusetts, the researchers found there were no significant differences in marijuana use between the state that had legalized medical marijuana and the state that had not.

"Our study did not find increases in adolescent marijuana use related to Rhode Island's 2006 legalization of medical marijuana," Choo said. "However, additional research may follow future trends as medical marijuana in Rhode Island and other states becomes more widely used."