Table 1.

Demographic Characteristics for Completers and Non-Completers

	All Participants	Participants with Complete Data	Participants without Complete Data	Significance Testing
Gender	52.5% female	54.5% female	49.3% female	Z = −3.38; p = .001
Age	15.87 (mean), 1.27 (SD)	15.93 (mean), 1.23 (SD)	15.78 (mean), 1.33 (SD)	t = −3.75; p < .001
Grade in School				Z = −6.50; p < .001
9th	30.7%	27.4%	35.5%
10th	27.6%	27.0%	28.3%
11th	25.7%	28.5%	21.5%
12th	16.0%	17.1%	14.4%
Average Grades	Mostly B’s (median)	Mostly B’s (median)	Mostly B’s (median)	Z = −1.39; p = .166
Ethnicity*
Caucasian	74.4%	78.4%	68.2%	Z = −6.71; p < .001
African-American	11.1%	8.6%	15.0%	Z = −7.71; p < .001
Asian	4.1%	4.0%	4.2%	Z = −0.43; p = .669
Hispanic/Latino	15.0%	13.2%	17.9%	Z = −4.24; p < .001
Other Ethnicity	14.3%	13.4%	18.2%	Z = −4.40; p < .001

^*= Ethnicity categories are non-exclusive (i.e., students were asked to select as many ethnic categories as applied to them); totals do not add up to 100%