Table 1.

Demographics across study components, parental income and education beginning when participants were 13 years of age

Demographics breakdown by analysis
	Exploratory factor analysis	Neuroimaging	Epigenetic	Neuroimaging & epigenetic
Total	184	82	112	59
Gender
Female	98	44	66	33
Ethnicity
White/Caucasian	58%	52%	57%	53%
Black/African American	29%	33%	29%	32%
Other	13%	15%	13%	15%
Parent’s highest education
Below high school	4%	6%	4%	7%
High school or GED	18%	17%	17%	14%
Some college or technical training	27%	29%	28%	29%
Associate’s degree	6%	4%	5%	3%
Bachelor’s degree	15%	11%	13%	8%
Some graduate work	7%	10%	9%	10%
Post college degree	19%	20%	18%	25%
Annual household income
Under $5,000	3%	4%	2%	2%
$5,000-$9,999	4%	4%	5%	5%
$10,000-$14,999	5%	5%	4%	5%
$15,000-$19,999	5%	5%	6%	5%
$20,000-$29,999	17%	18%	19%	22%
$30,000-$39,999	8%	7%	9%	7%
$40,000-$59,999	20%	23%	19%	22%
$60,000 or more	30%	27%	29%	27%