Table 3.
Linear Mixed Effects Model Coefficients and Associated Test Statistics
| Estimate | SE | t-value | p-value | d | |
|---|---|---|---|---|---|
| Fixed Effects | |||||
| Age | −0.01 | 0.01 | −1.09 | 0.29 | −0.01191 |
| Time 0 | −0.67 | 0.07 | −9.51 | < .001 | −0.6321 |
| Time 10 | −0.84 | 0.07 | −11.73 | < .001 | −0.79069 |
| Time 20 | −0.56 | 0.07 | −7.59 | < .001 | −0.53166 |
| Time 30 | −0.44 | 0.07 | −5.96 | < .001 | −0.41661 |
| BDNF | −0.19 | 0.32 | −0.60 | 0.56 | −0.17664 |
| Time 0 × BDNF | 0.72 | 0.10 | 7.29 | < .001 | 0.677257 |
| Time 10 × BDNF | 0.90 | 0.10 | 9.09 | < .001 | 0.847445 |
| Time 20 × BDNF | 0.51 | 0.10 | 5.09 | < .001 | 0.482617 |
| Time 30 × BDNF | 0.04 | 0.10 | 0.37 | 0.71 | 0.034079 |
| s2 | Std. Deviation | ||||
| Random Effects | |||||
| Subject ID | 0.3408 | 0.5838 |
Note: Reference level is baseline for “Time” and Val66Val for “BDNF”. Significant fixed effects and interactions are highlighted in bold. SE = standard error; d = Effect Size, calculated as the ratio of Estimate to square root of the sum of random effects variances; BDNF = brain-derived neurotropic factor (reference level = Val66Val); Time = time point (reference level = Baseline); s2 = random effect variance; Std. Deviation = standard deviation.