Table 1.

Demographic and clinical description of subject sample.

	Healthy controls (N = 18)	Cannabis users (N = 18)
Age (years)	17.2 ± 0.82	17.7 ± 0.94
Sex (N)	♀ 6 ♂ 12	♀ 2 ♂ 16
Handedness (N)	18 Right handed	18 Right handed
Age at first use (years)	–	14.86 ± 0.31
Age at regular use (years)	–	15.72 ± 0.20
Average frequency/ week	–	9.13 ± 1.96
Estimated lifetime uses	–	1351.94 ± 322.54
THCCOOH (ng)	–	429.16 ± 84.63
Family history of substance abuse	–	50%
History of other substance abuse	–	11%*
Current other substance abuse	–	–
History of tobacco use	–	22%
Current tobacco use	–	22%
History of psychiatric diagnosis	–	5%**
Current psychiatric diagnosis	–	–
HAM-A	1.27 ± 0.45	1.89 ± 0.62
HAM-D	0.78 ± 0.33	2.0 ± 0.71

Mean and SE for demographic variables, cannabis use dimensions, and HAM-A/HAM-D scores. Additionally, percentage of cannabis abusing and healthy control subjects with positive family history of substance abuse, history or current other substance abuse/tobacco use, or psychiatric diagnoses are reported. Estimates of lifetime cannabis use were calculated by summing the number of weeks since the age of reported first regular use until the week of the study visit and multiplying that value by the reported average frequency (episodes) of use per week.

HAM-A, Hamilton anxiety rating scale; HAM-D, Hamilton depression rating scale.

*Both identified subjects had a history of alcohol use.