Table 3.

Unadjusted and adjusted odds ratios for adolescent past-30-day marijuana use and past-30-day heavy marijuana use by state medical marijuana law (MML) status/ provisions, 1991–2011 (N=715,014).

	Any Marijuana Use		Heavy Marijuana Use ≥20^a

MML/Provision Status at the time of data year	^bUnadjusted OR (95%CI)	^cAdjusted OR (95%CI)	^bUnadjusted OR (95%CI)	^cAdjusted OR (95%CI)
Medical Marijuana Law - General

Any MML	1.08^***	0.93^*	1.12^***	1.00
12 states (n=102,124)	(1.03–1.13)	(0.86–0.99)	(1.05–1.21)	(0.89–1.13)

Years since enacted	1.01^*	0.99^*	1.01^*	0.99
Range (0–11)	(1.00–1.02)	(0.98–0.999)	(1.00– 1.02)	(0.98– 1.01)

≥4 years since enacted	1.14^***	0.98	1.19^***	0.98
6 states (n=58,107)	(1.06– 1.22)	(0.90–1.07)	(1.08– 1.30)	(0.88– 1.09)

Medical Marijuana Law - Provisions

Dispensary-related variables

Any dispensaries allowed	1.13 ^***	0.94	1.18^***	1.03
9 states (n=75,913)	(1.07– 1.19)	(0.87– 1.03)	(1.09– 1.28)	(0.89– 1.19)

Any active dispensaries by 2011	1.16 ^**	0.90	1.26^***	1.02
2 states (n=29,455)	(1.05– 1.29)	(0.78– 1.04)	(1.11– 1.45)	(0.84– 1.24)

Any for-profit dispensaries allowed	1.10^**	0.94	1.15^**	1.07
4 states (n=28,619)	(1.03– 1.17)	(0.83– 1.06)	(1.04– 1.28)	(0.88– 1.30)

MML Dispensary Index Score^d	1.03^**	0.97	1.04^*	1.01
Range (0–3)	(1.01– 1.06)	(0.94– 1.00)	(1.01– 1.08)	(0.95– 1.06)

MML Dispensary Index Score category (separate model for each individual score)

MML Dispensary Index Score 1	0.99	0.92	1.03	0.99
4 states (n=28,245)	(0 .92– 1.06)	(0.82– 1.02)	(0.92– 1.16)	(0.84– 1.17)
MML Dispensary Index Score 2	1.37^***	1.01	1.23^***	0.86
3 states (n=18,127)	(1.28– 1.47)	(0.91– 1.12)	(1.09– 1.39)	(0.74– 1.01)
MML Dispensary Index Score 3	1.10^*	0.94	1.13^*	1.04
5 states (n=28,191)	(1.02– 1.19)	(0.84– 1.05)	(1.02– 1.27)	(0.87– 1.25)

Home Cultivation and Allowed Plant Limit

Home cultivation allowed	1.08^**	0.92	1.14^***	0.97
10 states (n=98,168)	(1.03– 1.13)	(0.85– 1.00)	(1.06– 1.22)	(0.86– 1.11)

Number of plants limit	1.01	1.04	1.01^**	1.02
Range (0–16)	(1.01– 1.01)	(1.02– 1.06)	(1.00– 1.01)	(1.00– 1.05)

≥10 plants allowed	1.07	0.92	1.14^*	0.98
4 states (n=32,583)	(0.99– 1.14)	(0.82– 1.03)	(1.02–1.26)	(.83– 1.14)

Allowed Possession Amounts

Number usable ounces limit	1.05^***	1.21^***	1.04^***	1.18
Range (0–10)	(1.04– 1.05)	(1.09– 1.34)	(1.03– 1.04)	(0.99– 1.40)

≥2.5 usable ounces limit	1.08^**	0.92	1.15^***	0.97
6 states (n=57,167)	(1.03– 1.14)	(0.84– 1.01)	(1.06– 1.25)	(0.85– 1.11)

Patient Registry Requirement

Registration Voluntary	1.27^***	1.41^***	1.31^***	1.23^**
1 State (n=28,149)	(1.17– 1.37)	(1.28– 1.56)	(1.20– 1.43)	(1.08– 1.40)

Caregivers (All MML states allow caregivers to supply patients with medical marijuana)

Number of patients limit per caregiver	1.02^**	0.98	1.03^***	1.00
Range (0–5)	(1.01– 1.03)	(0 .97– 1.00)	(1.01– 1.05)	(0.97– 1.02)

5 patients per caregiver allowed	1.07^*	0.91	1.14^**	0.97
6 states (n=50,777)	(1.01– 1.15)	(0.82– 1.01)	(1.04– 1.26)	(0 .83– 1.13)

MML Provision Index Variables

Provision Index Score^e	1.02^***	0.98^*	1.04^***	1.00
Range (0–5)	(1.01– 1.04)	(0.96– 0.998)	(1.02– 1.06)	(0.96– 1.03)

Provision Index Score (separate model for each individual score)

Provision Index Score 1	1.10^***	1.04	1.06	1.07
3 states (n=27,260)	(1.04– 1.16)	(0.94– 1.14)	(0.98– 1.16)	(0.93– 1.23)

Provision Index Score 2	0.98	0.92	0.95	1.07
2 states (n=10,527)	(0.89– 1.08)	(0.79– 1.07)	(0.82– 1.09)	(0.84– 1.36)

Provision Index Score 3	1.47^***	1.03	1.33^*	0.86
1 state (n=2,299)	(1.26– 1.72)	(0.88– 1.19)	(1.04– 1.69)	(0.67–1.11)

Provision Index Score 4	1.09^*	0.92	1.16^**	0.97
5 states (n= 34,477)	(1.01– 1.17)	(0.83– 1.02)	(1.04– 1.29)	(0.84– 1.13)

Provision Index Score 5	1.17^***	0.90	1.28^***	1.02
1 state (n=24,923)	(1.07– 1.28)	(0.78– 1.03)	(1.15– 1.42)	(0.84– 1.25)

Each row shows the unadjusted and adjusted model results for each independent variable with the two dependent variables in the columns. Stata 13 MP “svyset” survey data settings were used to assign YRBS design variables: [sampling units: 'psu' and strata 'stratum'] as provided by all state YRBS datasets to account for their sampling procedures.

Each cell shows the result of a separate logistic regression analysis. Control groups included: (1) all states without MMLs in any of the years of data collection (Medical Marijuana Law – General analyses) and (2) states without MMLs in any of the years of data collection combined with states with MMLs that did not have the specific provision assessed in each model (Medical Marijuana Law – Provisions analyses).

⁺

MML does not include policies permitting high concentration Cannabidiol products for medicinal purposes.

Estimates are weighted using YRBS weights [*p ≤.05, **p≤.01, ***p≤.001].

Heavy marijuana use coded “1” if adolescent reported use 20≤ times in past-30-days

Unadjusted, bivariate models.

Adjusted for: year fixed effects, state fixed effects, and individual demographics: age, gender, White, Black, Hispanic, and other.

Dispensary Index Score range 0–3: Analyzed as an ordinal variable, and as separate dichotomous variables (one for each individual score 1–3). Categories: 0=States with no MMLs; 1=State has MML, but dispensaries not allowed, 2=Dispensaries allowed, 3=Dispensaries allowed and either active in 2011 and/or for-profit dispensaries allowed

Provision Index Score range 0–5: Analyzed as an ordinal variable, and as separate dichotomous variables, one for each individual score 1–5; [0=States with no MMLs; 1=Home cultivation and/or caregivers allowed; 2–5=Enumeration of state MMLs inclusion of more liberalized provisions in addition to home cultivation and caregivers: (a) Dispensaries for profit OR dispensaries active in 2011, (b) Home cultivation ≥10 plants allowed, (c) Possession: ≥2.5usable ounces allowed, (d) Caregivers allowed 5 patients, and (e) Patient registry voluntary].