Gauhar, Ghazal (2025) Cannabis Legalization and Cognitive Skills of Canadians A Difference-in-Differences Analysis. Masters thesis, Concordia University.
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Abstract
The legalization of recreational cannabis in Canada in 2018 marked one of the most pivotal
public policy shifts of the past decade, drawing attention to its broader social and cognitive
effects. This study examines how adult cognitive skills in Canada evolved over the decade surrounding
the legalization of recreational cannabis in 2018. Using nationally representative
microdata from the 2012 and 2022 waves of the Programme for the International Assessment
of Adult Competencies (PIAAC), the analysis compares changes in literacy, numeracy,
and problem-solving scores in Canada with those observed in Germany and Ireland, two advanced
economies that did not implement similar legislative reforms during the same period.
The study applies a difference-in-differences framework and controls for demographic and
educational factors, focusing on population-level patterns rather than individual behavioural
responses. Across all three countries, average cognitive scores increased between 2012 and
2022, but the magnitude of improvement differed. The estimates indicate that gains in Canada
were smaller than those observed in the pooled comparison group, although the differences
were modest and consistent with descriptive evidence. These results should be interpreted as
relative changes in national trends rather than as evidence of a direct effect of legalization. The
findings contribute to a limited body of research linking large-scale policy environments to
standardized skill outcomes among adults and highlight the importance of considering demographic
change, educational systems, and broader social developments when interpreting shifts
in national performance. Moreover, this study adds to the literature that looks at how wider
policy settings relate to adult skill outcomes. They also serve as a reminder that demographic
aging, differences in education systems, and other social or economic developments all shape
how cognitive scores move over time.
| Divisions: | Concordia University > Faculty of Arts and Science > Economics |
|---|---|
| Item Type: | Thesis (Masters) |
| Authors: | Gauhar, Ghazal |
| Institution: | Concordia University |
| Degree Name: | M.A. |
| Program: | Economics |
| Date: | December 2025 |
| Thesis Supervisor(s): | Sigouin, Christian |
| Keywords: | Cannabis legalization; cognitive skills; difference-in-differences; adult literacy and numeracy; problem-solving skills; PIAAC; cross-country comparison; Canada; Germany; Ireland; population-level analysis; education and human capital |
| ID Code: | 996625 |
| Deposited By: | Ghazal Gauhar |
| Deposited On: | 29 Jun 2026 14:23 |
| Last Modified: | 29 Jun 2026 14:23 |
| Additional Information: | This thesis examines population-level changes in adult cognitive skills in Canada that evolved around the legalization of recreational cannabis, using internationally comparable survey data. The analysis emphasizes relative trends across countries rather than causal effects and highlights the role of demographic and educational factors in shaping national skill outcomes. |
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