Table 4.
Results from Regression Analyses Predicting Adolescent Cortisol Changes
| Step | Variable | ΔR2 | Std. β | t | p |
|---|---|---|---|---|---|
| 1 | Control Variables | .108 | .07 | ||
| Youth Ethnicitya | |||||
| African American | 0.00 | 0.99 | .99 | ||
| Hispanic | −0.04 | 0.65 | .65 | ||
| Native American | 0.07 | 0.67 | .50 | ||
| Other | 0.00 | −0.05 | .96 | ||
| Income-to-Needs Ratio | 0.11 | 1.13 | .26 | ||
| Time of Day | 0.27 | 2.84 | <.01 | ||
| 2 | Parent Cortisol Change | .039 | −0.28 | −2.15 | .03 |
| 3 | Parent Genotypeb | .002 | 0.04 | 0.42 | .68 |
| 4 | Parent Cortisol Change ☓ Genotype | .003 | 0.08 | 0.57 | .57 |
| Overall R2 | .151 | .05 | |||
Note: Standardized regression coefficients. Each step incorporates all predictors from the previous step.
a
Dummy coding was used to incorporate ethnicity in the model with European Americans used as the reference group.
b
1 = AA/AG and 2 = GG;