Table 2.

Cannabis and other substance use

		Current use
	Abstinent (n=63)	Low use (n=24)	Heavy use (n=24)	Total (N=111)
Age at first cannabis use, Mean(SD)*	13.8 (3.3)	16.3 (4.3)	15.3 (2.7)	14.6 (3.6)
Age at the heaviest cannabis use, Mean(SD)	31.1 (11.1)	30.5 (9.0)	29.4 (11.7)	31.1 (11.4)
Cannabis use during the heaviest use (%)
Days per week**
Less than one day a week	0.0	8.3	0.0	1.8
One day a week	0.0	4.2	0.0	0.9
2–3 days a week	3.2	12.5	0.0	4.4
4–5 days a week	12.7	29.2	16.7	16.8
More than 5 days a week	84.1	45.8	83.3	76.1
Times per day
Once a day	1.61	4.2	0.0	1.8
2–3 times a day	12.9	33.3	8.3	17.0
4–5 times a day	27.4	25.0	25.0	26.8
6–7 times a day	11.3	12.5	33.3	16.1
More than 7 times a day	46.8	25.0	33.3	38.4
Reduction from heaviest to current use (%)	100	79.2	25.0	79.3
Marijuana Motives Questionnaire (MMQ), Mean (SD)
Coping	3.3 (1.2)	3.0 (1.2)	3.7 (1.1)	3.3 ( 1.2)
Social	3.1 (1.2)	2.9 (1.2)	3.1 (1.3)	3.1 (1.2)
Enhancement*	4.0 (1.0)	3.3 (1.1)	3.6 (0.8)	3.8 (1.0)
Conformity	1.8 (1.0)	1.8 (1.0)	1.5 (0.7)	1.7 (1.0)
Expansion	2.7 (1.4)	2.6 (1.2)	3.2 (1.3)	2.8 (1.3)
Use in the past 30 days (%)
Tobacco	55.6	45.8	50.0	51.3
Alcohol**	3.2	41.7	54.2	22.1
Other drug use**	3.2	16.7	25.0	10.6

Group comparison based on Chi-square test for categorical variables or ANOVA test for continuous variables

^*P<0.05,

^**P<0.01