Table 1.

Sociodemographic characteristics

	Exchanged (n = 569) %	Never Exchanged (n = 11051) %	Unadjusted odd ratio (95% CI)
Gender
Male	58.4	46.4	Referent
Female	41.6	53.6	.618 (.521 to.733)
Age (Mean, SE)	21.6 (1.6)	21.6 (1.6)	1.01 (.963 to 1.06)*
Race/Ethnicity
White	51.8	69.1	Referent
African American	42.5	21.2	2.72 (2.29 to 3.23)
Asian	4.2	7.7	.575 (.391 to .846)
Native American	1.4	1.9	.902 (.611 to 1.33)*
Education Level
More than high school	30.8	45.1	Referent
High school or less	69.2	54.8	2.73 (2.28 to 3.28)

Note. All outcomes are significant at p<.05, unless indicated otherwise by an asterisk (*)