Table 2.

Seven-Class Model of Past 12-Month Marijuana Use from Ages 18 through 50

Modal Age	Overall Proportion	Non- Users	Early YA Moderate Users	YA Moderate Users	Persistent Moderate Users	Early YA Heavy Users	YA Heavy Users	Persistent Heavy Users
		Latent Class Membership Probabilities
		0.44	0.22	0.12	0.06	0.06	0.05	0.05
		Item Response Probabilities
	0 Occasions in past 12 months
18	0.53	0.90	0.31	0.43	0.15	0.07	0.07	0.08
19/20	0.53	0.95	0.23	0.34	0.12	0.02	0.07	0.04
21/22	0.56	0.95	0.44	0.22	0.14	0.03	0.00	0.02
23/24	0.62	0.96	0.69	0.18	0.15	0.08	0.01	0.02
25/26	0.68	0.98	0.90	0.20	0.18	0.21	0.02	0.03
27/28	0.74	0.98	0.96	0.47	0.17	0.40	0.03	0.03
29/30	0.79	0.99	0.98	0.65	0.25	0.63	0.07	0.03
35	0.84	1.00	0.96	0.86	0.30	0.86	0.29	0.03
40	0.86	1.00	0.96	0.93	0.22	0.96	0.48	0.04
45	0.88	1.00	0.95	0.98	0.38	0.95	0.61	0.03
50	0.88	1.00	0.95	0.95	0.44	0.91	0.65	0.09
	1-39 Occasions in past 12 months
18	0.33	0.10	0.59	0.51	0.60	0.37	0.36	0.32
19/20	0.32	0.05	0.70	0.64	0.62	0.26	0.22	0.23
21/22	0.30	0.05	0.55	0.73	0.67	0.32	0.13	0.18
23/24	0.26	0.04	0.30	0.79	0.73	0.50	0.11	0.17
25/26	0.22	0.02	0.10	0.78	0.76	0.58	0.16	0.14
27/28	0.18	0.02	0.04	0.51	0.78	0.53	0.30	0.13
29/30	0.14	0.01	0.02	0.34	0.68	0.36	0.42	0.16
35	0.11	0.01	0.04	0.13	0.62	0.13	0.53	0.15
40	0.09	0.00	0.04	0.07	0.70	0.04	0.45	0.16
45	0.08	0.00	0.05	0.02	0.56	0.05	0.38	0.24
50	0.08	0.01	0.04	0.04	0.49	0.07	0.31	0.24
	40+ Occasions in past 12 months
18	0.14	0.00	0.10	0.06	0.25	0.56	0.56	0.61
19/20	0.14	0.00	0.07	0.01	0.26	0.72	0.72	0.73
21/22	0.14	0.00	0.01	0.05	0.19	0.65	0.86	0.80
23/24	0.12	0.00	0.00	0.04	0.13	0.43	0.87	0.81
25/26	0.10	0.00	0.00	0.03	0.06	0.20	0.82	0.84
27/28	0.08	0.00	0.00	0.02	0.05	0.07	0.67	0.85
29/30	0.07	0.00	0.00	0.01	0.07	0.01	0.51	0.81
35	0.05	0.00	0.00	0.01	0.08	0.01	0.19	0.82
40	0.04	0.00	0.00	0.00	0.08	0.00	0.07	0.80
45	0.04	0.00	0.00	0.00	0.07	0.00	0.01	0.73
50	0.04	0.00	0.00	0.01	0.08	0.02	0.04	0.67

Notes: Unweighted n=9,831. YA = young adult. Bold font indicates item-response probabilities of >.50. Latent class membership probabilities sum to 1 horizontally. Item response probabilities (reflecting the probabilities of each level of use for the sample overall, as well as within latent classes), sum to 1 vertically within age. For example, at age 18, the overall probability of not using marijuana use in the past 12 months was 0.53, the probability of using on 1-39 occasions was 0.33, and was 0.14 for using on 40+ occasions.