Table 1.
Sample characteristics (means and standard deviations, or distribution).
| ADHD (N = 74) | TD (N = 30) | ||
|---|---|---|---|
| Age | 8.60 (1.62) | 8.03 (1.82) | t(102) = −1.57 n.s. |
| Sex (% boys) | 64.86% | 63.33% | χ2(1) = 0.02 n.s. |
| IQ | 96.09 (13.26) | 101.31 (10.81) | t(101) = 1.89 n.s. |
| Parental education level | 5.26 (1.03) | 6.05 (0.58) | U = 479.0 *** |
| Inattention symptoms | 7.05 (1.52) | 1.53 (1.43) | U = 2119.5 *** |
| Hyp.–Imp. symptoms | 6.24 (2.16) | 1.27 (1.29) | U = 2123.0 *** |
| ODD symptoms | 2.89 (2.14) | 0.73 (1.29) | U = 1798.5 *** |
Note: *** p < 0.001, ** p < 0.01. For all variables except sex, means are reported, with standard deviations in parentheses. Abbreviations: ADHD = Attention-Deficit/Hyperactivity Disorder, Hyp.–Imp. = Hyperactivity–Impulsivity, n.s. = not significant, ODD = Oppositional Defiant Disorder, TD = Typically Developing. Age was analyzed in months but reported in years to enhance readability.