TABLE 7.
Cohort 2: results of ME growth models for changes in ANS RT (in sec.) from grade 5 to grade 9.
| Variables | Baseline | Model 1 | Model 2 | Model 3 | Model 3a |
| Intercept-only | Linear growth | Non-linear growth | Model with random slope1 | Model with random slope2 | |
| B (s.e.) | B (s.e.) | B (s.e.) | B (s.e.) | B (s.e.) | |
| Fixed effect | |||||
| Constant | 0.92*** (0.01) | 1.00*** (0.01) | 1.05*** (0.01) | 1.05*** (0.02) | 1.04*** (0.02) |
| Time | −0.04*** (0.004) | −0.14*** (0.01) | −0.14*** (0.02) | −0.14*** (0.02) | |
| Time2 | 0.02*** (0.003) | 0.03*** (0.003) | 0.02*** (0.003) | ||
| Random effect | |||||
| Intercept variance | 0.02 | 0.02 | 0.02 | 0.04 | 0.04 |
| Residuals | 0.03 | 0.03 | 0.03 | 0.02 | 0.02 |
| Slope variance (time) | 0.002 | 0.02 | |||
| Slope variance (time2) | 0.001 | ||||
| Covariance between intercept and slope (time) | −0.007 | −0.02 | |||
| Covariance between intercept and slope (time2) | 0.002 | ||||
| Covariance between slope (time) and slope (time2) | −0.004 | ||||
| Log-likelihood | 131.94 | 172.40 | 198.99 | 219.75 | 234.05 |
| LR test (Δ df) | 80.92*** (1) | 53.19*** (1) | 41.51*** (2) | 28.59*** (3) | |
| ICC | 0.31 | ||||
***p < 0.001.