Table 2.

Simultaneous Cannabis/Alcohol Use After Versus Before Legalization of Recreational Cannabis by Age Groups Among U.S. Individuals. NSDUH 2008–2019

Age groups	% who reported simultaneous cannabis/alcohol use		AOR (95%CI)
	After MCL/ Before RCL	After MCL/ After RCL
12–20	9.31	8.44	0.90 (0.78, 1.04)
21–30	9.20	10.40	1.15 (1.04, 1.27)
31–40	5.12	6.12	1.21 (1.04, 1.41)
41–50	2.93	4.68	1.63 (1.34, 1.98)
51+	1.72	2.13	1.25 (0.99, 1.58)

NSDUH National Survey on Drug Use and Health, RCL recreational cannabis laws, AOR adjusted odds ratio

All states that legalized recreational cannabis previously legalized medical cannabis. The before versus after RCL contrast therefore compared simultaneous cannabis/alcohol prevalence in states after MCL but before RCL relative to simultaneous cannabis/alcohol prevalence in states after MCL and after RCL

Individual- and state-level predictors: state random effects, year fixed effects, gender, race/ethnicity, family income, and urbanicity, % white, % male, % ages 10–24, % of adults (<25) with at least a high school education, unemployment, and state’s median household income

For point estimates with corresponding lower limit 95% confidence interval (LL95%CI) greater than 1, we estimated e-values to quantify the minimum strength of the relationship between an unmeasured/uncontrolled confounder and both our exposure (RCL) and outcome (simultaneous cannabis/alcohol use) needed to reduce the aOR and the lower limit of the 95% confidence interval (LL95%CI) to the null. For age group 21–30 years, these were as follows: ae-value for aOR = 1.55 and LL95%CI = 1.23; for age group 31–40 years, these were as follows: ae-value for aOR = 1.71 and LL95%CI = 1.22; and for age group 41–50 years, these were as follows: ae-value for aOR = 2.63 and LL95%CI = 2.01