Table 1.
Parameter estimates from three multi-level models assessing developmental trajectories from grade 1 to Age 15
| Model parameters | Beta coefficient | SD | p-value |
|---|---|---|---|
| Model for social skills | |||
| Intercept | 103.04 | 2.0 | <.001 |
| Grade | −2.04 | .28 | <.001 |
| Grade^2 | −.25 | .03 | <.001 |
| Menarche.Early | −0.92 | 1.64 | .577 |
| African American | −9.56 | 2.26 | <.001 |
| Grade* Menarche.Early | .88 | .47 | .059 |
| Grade^2* Menarche.Early | .13 | .05 | .012 |
| Mom's age | −.13 | .14 | .341 |
| Mom's education | .98 | .34 | .004 |
| SES | .48 | .24 | .059 |
| Living with partner | −1.0 | 1.83 | .586 |
| Random effects: τ0 = 13.02 [95% CI: 11.89;14.28]; τ1 = 1.42 [1.23; 1.64]; σ2 = 8.49 [8.19; 8.79] | |||
| Model for internalizing problems | |||
| Intercept | 46.48 | 1.23 | <.001 |
| Grade | −.25 | .17 | .139 |
| Grade^2 | −.01 | .02 | .646 |
| African American | −2.47 | 1.39 | .076 |
| Menarche.Early | 1.84 | 1.03 | .074 |
| Grade* Menarche.Early | −.55 | .29 | .052 |
| Grade^2* Menarche.Early | −.09 | .03 | .007 |
| Mom's age | −.18 | .09 | .038 |
| Mom's education | −.03 | .21 | .868 |
| SES | .25 | .15 | .092 |
| Living with partner | .87 | 1.13 | .44 |
| Random effects: τ0 = 8.19 [7.49; 8.97]; τ1 = .69 [.57; .84]; σ2 = 5.32 [5.14; 5.51] | |||
| Model for externalizing problems | |||
| Intercept | 47.14 | 1.15 | <.001 |
| Grade | .11 | .12 | .374 |
| Grade^2 | .06 | .01 | <.001 |
| Mom's Age | −.20 | .09 | .027 |
| Mom's education | −.50 | .22 | .022 |
| SES | −.36 | .16 | .024 |
| Living with partner | .52 | 1.15 | .650 |
| Random effects: τ0 = 9.57 [8.84; 10.36]; τ1 = .79 [.68; .91]; σ2 | |||