Table 4.
Linear mixed models.
| Span direction | Random intercept variance | Predictors | t | p |
|---|---|---|---|---|
| Forward | 0.77, SD = 0.88 | Age | 1.2 | .25 |
| CTONI-2 | 2.7 | .01 | ||
| Stimulus (digits−objects) | 1.1 | .25 | ||
| Stimulus (digits−symbols) | −0.7 | .52 | ||
| Stimulus (objects−symbols) | −1.7 | .07 | ||
| Rapid digit naming | 2.2 | .03 | ||
| Nonword repetition | 3.1 | < .01 | ||
| PPVT | 4.9 | < .01 | ||
| PPVT:stimulus (digits−objects) | −3.6 | < .01 | ||
| PPVT:stimulus (digits−symbols) | −4.2 | < .01 | ||
| PPVT:stimulus (objects−symbols) | −0.53 | .59 | ||
| Backward | 1.08, SD = 1.04 | Age | 1.0 | .33 |
| CTONI-2 | 3.4 | .01 | ||
| Stimulus (digits−objects) | 1.9 | .06 | ||
| Stimulus (digits−symbols) | 3.0 | < .01 | ||
| Stimulus (objects−symbols) | 1.1 | .27 | ||
| Rapid digit naming | 4.3 | < .01 | ||
| PPVT | 5.7 | < .01 | ||
| PPVT:stimulus (digits−objects) | −4.0 | < .01 | ||
| PPVT:stimulus (digits−symbols) | −6.1 | < .01 | ||
| PPVT:stimulus (objects−symbols) | −2.1 | .03 |
Note. Significant contributors to the model are denoted in bold. A minus sign (−) denotes the effect of changing levels of the variable stimulus—for example, the variance due to shifting stimuli from digits to objects. A colon (:) denotes an interaction term. CTONI-2 = Comprehensive Test of Nonverbal Intelligence–Second Edition; PPVT = Peabody Picture Vocabulary Test.