Table I:

Descriptive Statistics of the COGA Discovery Sample

	EA		AA
	N/Mean	%/SD	N/Mean	%/SD	Range
Female	4000	53.5%	1,788	52.6%	-
Age	35.1	15.4	31.4	12.7	12.0 – 91.0	*
Externalizing Score	0.0	1.0	0.1	1.0	−0.9 – 3.9
DSM-IV Symptom Counts:
Alcohol Dependence	2.1	2.4	1.9	2.7	0 – 7	*
Alcohol Abuse	1.0	1.3	0.7	1.2	0 – 4	*
Illicit Drug Dependence	1.2	2.2	1.8	2.5	0 – 7	*
Illicit Drug Abuse	0.5	0.9	0.4	0.8	0 – 4	*
Antisocial Personality Disorder/Conduct Disorder	1.7	1.9	2.2	2.1	0 – 7	*

^*Differences across EA and AA p <.05 (Chi-square/ T-test)

EA = European ancestry, AA = African ancestry