Table 1.

Characteristics of Research Participants

	Healthy Control	Methamphetamine-Dependent
Sample size	41	32
Age	34.2 ± 8.7	34.6 ± 10.8
Education (yr.)	13.0 ± 1.6	12.4 ± 1.3
Mother’s Education (yr.)	12.6 ± 2.9	12.3 ± 3.2
Ethnicity
Caucasian	15	16
African Am.	6	1
Hispanic	14	10
Other	6	5
Gender
Male	23	17
Female	18	15
Cigarette Smokers (yes/no)	8/41	30/32***
Cigarettes/day (smokers only)	9.7 ± 7.3	12.5 ± 12.7
Days Alcohol/Past 30	1.9 ± 3.3	3.8 ± 6.6
Days Marijuana/Past 30	1.6 ± 5.2	3.3 ± 7.7
Days Methamphetamine/Past 30	--	20.7 ± 8.4
Duration of Methamphetamine abuse (yr.)	--	7.6 ± 6.0
Grams Methamphetamine/week	--	2.8 ± 3.0
Days between BIS Administrations	16.2 ± 7.2	10.5 ± 6.5**†
BIS 1 Total Score	56.1 ± 10.1	67.2 ± 11.2***
BIS 2 Total Score	56.6 ± 11.0	70.7 ± 11.9***

Note. Values are means ± SDs, where appropriate. The symbols, ** and ***, indicate significant differences from the respective control group at p < 0.01 and p < 0.001, respectively.

^†For outpatient methamphetamine users, the days between BIS administrations were not always equivalent to the days of abstinence at retesting.