Editorial

Advancing knowledge on cannabis policy using evidence from North America

Over the previous two decades, the lifetime prevalence of cannabis use has risen among Mexico’s population.

Estimate the sex- and age-specific rates of onset of cannabis use over time.

Five nationally representative cross-sectional surveys, the Mexican National Surveys of Addictions (1998, 2002, 2008, 2012) and the Mexican National Survey on Drugs, Alcohol, and Tobacco Consumption (2016).

Mexico.

Pooled sample of 141,342 respondents aged between 12 and 65 years of which 43.6%(n = 61,658) are male and 56.4% (n = 79,684) are female.

We estimated the age-specific rates of onset of cannabis as the conditional rate of consuming cannabis for the first time at a specific age.

Time-to-event flexible-parametric models with spline specifications of the hazard function. Stratified analysis by sex and control for temporal trends by year of data collection or decennial birth cohort.

Age-specific rates of onset of cannabis use per 1,000 individuals increased over time for females and males. Peak rates of onset of cannabis use per 1,000 ranged from 0.935 (95%CI = [0.772, 1.148]) in 1998, to 5.391 (95%CI = [4.924, 5.971]) in 2016 for females; and from 7.513 (95%CI = [6.732, 10.063]) in 1998, to 26.107 (95%CI = [25.918,30.654]) in 2016 for males. Across decennial birth-cohorts, peak rates of onset of cannabis use per 1,000 individuals for females ranged from 0.234 (95%CI = [0.078, 0.768]) for those born in the 1930s, to 14.611 (95%CI = [13.243, 16.102]) for those born in the 1990s; and for males, from 4.086 (95%CI = [4.022, 7.857]) for those born in the 1930s, to 38.693 (95%CI = [24.847, 48.670]) for those born in the 1990s.

Rates of onset of cannabis increased over the previous two decades for both females and males but remained higher for males. Across recent cohorts, the rates of onset have increased at a faster rate among females than males.

With the State of California legalizing recreational cannabis sales on January 1, 2018, the regulatory process is once more in the forefront of cannabis research. Colorado, often held up as a model of legalization policy, was the first state to implement retail sale of recreational cannabis on January 1^st, 2014. However, a combination of subsequent under-regulation and over-regulation, inconsistently applied across issues such as retail licencing, chemical testing, cannabis derivatives, municipality approval for growers, and financing, have not only held back the industry in Colorado but also negatively impacted public health, oversight, and have potentially increased the availability of illegal cannabis. We argue that a data-analytic approach to the industry is potentially the most effective way to resolve these concerns, since in the absence of consistent and reliable data, policymakers are apt to satisfy individual policy concerns without considering the industry as a whole. In this paper we present a data-analytic framework for the cannabis industry, offering a theoretically-driven justification for our approach, and describe implications for research on drug and information policy. The framework may serve as a model for other states or countries contemplating cannabis legalisation. As four new states legalised recreational cannabis in 2016, the implications of this research for policymakers has dramatically increased.