Table 1.

Demographics for the population (mean±SD).

	Cannabis dependent (N = 44)	Nondependent (N = 30)	Two-tailed p value
Gender	34 M, 10 F	21 M, 9 F	0.50
Age (years)	23.7 ± 6.5	24.8 ± 8.2	0.55
Education (years)	13.6 ± .3	13.4 ± 2.2	0.82
Mean age of onset (years)a	17.3 ± 2.5	17.4 ± 2.6	0.88
Mean duration of cannabis  use (years)	5.5 ± 5.5	7.7 ± 7.5	0.17
Mean # cannabis use  occasions/dayb	3.4 ± 2	4 ± 4	0.53
Total score on MPSc	4.8 ± 5.2	2.3 ± 2.6	0.02
Mean # alcohol drinks/month	7.8 ± 6.6	7.1 ± 7.2	0.71
Mean # cigarettes/day	3 ± 5.2	5.6 ± 7.5	0.14
IMPSSd	9.4 ± 3.8	8.9 ± 4.1	0.63
BIS-Briefe	14.8 ± 3.6	13.8 ± 4.1	0.35

MPS, Marijuana Problem Scale; IMPSS, Impulsivity and Sensation Seeking Scale; BIS, Barratt Impulsiveness Scale.

^aDependent (n = 34), nondependent (n = 24).

^bDependent (n = 31), nondependent (n = 21).

^cDependent (n = 33), nondependent (n = 22).

^dDependent (n = 26), nondependent (n = 21).

^eDependent (n = 35), nondependent (n = 24).