the health strategist
institute for strategic health transformation
& digital health
Joaquim Cardoso MSc.
Chief Research and Strategy Officer (CRSO),
Chief Editor and Senior Advisor
September 13, 2023
What is the message?
While there is a positive association between marijuana use and high school dropout rates, this relationship is not primarily driven by marijuana’s direct effects on cognitive function.
Instead, the study suggests that unobservable factors, peer associations, and family influences play a more significant role in explaining the connection.
Additionally, the inclusion of cigarette smoking in the analysis highlights the importance of considering a broader range of variables when examining the link between marijuana use and educational outcomes.
One page summary:
In this study, the authors investigate the complex relationship between marijuana use and high school dropout rates, shedding new light on the potential causal factors behind this association.
The research is driven by the need to distinguish between marijuana’s direct impact on cognitive function and its correlation with other variables that may influence educational outcomes.
The introduction highlights the well-established connection between early marijuana use and low educational attainment, such as dropping out of high school or fewer years of education. This relationship has often been attributed to marijuana’s effects on memory, attention, motivation, or cognitive function.
However, the authors point out that alternative explanations exist, including the possibility that poor educational outcomes precede marijuana use or that a common third variable is responsible for both.
To address these complexities, the study employs two key methodologies. Firstly, it utilizes propensity score methods to create matched groups of marijuana users and non-users with similar baseline characteristics, minimizing selection biases. Secondly, the research evaluates changes in various factors over time, acknowledging that adolescents’ environments and behaviors evolve.
The results indicate a positive association between marijuana use and high school dropout rates. However, when accounting for baseline differences in observable characteristics, this association is significantly reduced.
Intriguingly, the remaining connection becomes statistically insignificant after adjusting for cigarette smoking, a variable not typically considered in economic analyses.
This suggests that the link between marijuana use and high school dropout is more likely due to omitted variable bias or the influence of factors such as peer associations and family influences.
The study delves into various potential explanations for this bias, including unobserved characteristics, deviant behaviors, and risk factors associated with both marijuana and cigarette use.
It concludes that peer associations and family influences in grades 8, 9, or 10 are the primary factors that account for the relationship between marijuana use and high school dropout, with cigarette use being a significant correlate.
The research also highlights the limitations of the study, emphasizing that it only examines data from South Dakota and that measurement errors or limitations in assessing certain baseline constructs may still introduce unobservable factors that bias the results.
In conclusion, this study challenges the conventional understanding of the link between marijuana use and high school dropout rates.
It suggests that the association may not be driven primarily by marijuana’s direct impact on cognitive function but rather by unobserved variables, emphasizing the importance of considering a broader range of influences when studying this relationship.
Moreover, it raises questions about the appropriateness of certain instrumental variables in identifying causal associations in similar research.
DEEP DIVE
This summary was written based on the article “Marijuana Use and Highschool Dropout”, published by the National Library of Medicine and written by Daniel F. McCaffrey, Rosalie Liccardo Pacula, Bing Han, and Phyllis Ellickson, on November, 20, 2009.
To read the full article, access https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2910149/
