Appendix A.

Comparison of Wave I factors among those who leave and stay in the study

	Out of sample	In sample		N
Sociodemographics
Race/ethnicity
NH White	.55	.47	***	20756
NH Black	.24	.22	***	20756
Hispanic	.20	.16	***	20756
Asian/Pacific Islander	.08	.06	***	20756
Other	.02	.01	***	20756
Female	.49	.51	***	20774
Age	15.78	15.67	***	20774
U.S.-born	.87	.92	***	20733
Health
Smoker	.26	.26		20416
BMI	22.35	22.65	***	20175
Depressive symptoms scale	.04	−.02	***	20704
Cognitive test score	97.09	100.82	***	19713

Source: Add Health.

Notes: Sample sizes differ due to item missingness.

^***p < .001