Perceived risk of harm still relevant

In the Monitoring the Future study (MTF) high school students convey how much they think people risk harming themselves if they smoke marijuana regularly. Typically, the riskier they think it is, the less likely the students are to use marijuana. This risk/use association has made perceived risk of harm a powerful ingredient of prevention programs for youth.



However, in the last decade risk and use no longer track as mirror images. From 2006 to 2016, MTF 12th graders showed a 45% decline in perceived risk of harm from smoking marijuana regularly but only a 13% increase in past-year marijuana use. Lower risk perception appears not to be linked strongly to increases in use and this raises the question whether perceived risk of harm is still an effective deterrent of use.



Recently Terry-McElrath and other MTF researchers published a paper in Addictive Behaviors showing that perceived risk does continue to be a strong protective factor against adolescent marijuana use. Among those who saw great risk of harm from regular marijuana use (asked from 1991 to 2016), the risk/use association has remained stable for 12th graders overall, females, males, and white students; the risk/use association has increased in strength among Hispanic students but weakened among black students. For those who indicate moderate risk of harm, the risk/use association has become stronger for 12th graders in general, females, males, white and Hispanic students, and black students until 2005. The declining levels of marijuana use among teens have not favored any one level of risk (none, slight, moderate, or great).



The results suggest that in general the risk/use association is actually increasing over time for most demographic groups, meaning that seeing greater risk is still linked to lower likelihood of using marijuana. Good information on risk of harm continues to be an important component of marijuana prevention efforts. Among black 12th graders, decreasing perceptions of great risk and leveling perceptions of moderate risk may be linked to recent rapid increases in marijuana use in this group. Understanding how risk perceptions work and what prevention strategies are especially effective when risk perceptions decline also continues to be important.



Findings are based on surveys from 275,768 US 12th graders who answered MTF questions on marijuana use, perceived risk, gender, and race/ethnicity from 1991 to 2016. Monitoring the Future is funded by the National Institute on Drug Abuse.