Table 1.
Demographics of the sample.
| ADHD (210) | Unaffected siblings (108) | Subthreshold Subjects (49) | Controls (141) | |
|---|---|---|---|---|
| Age (years) | 14.61 ± 2.41 | 14.59 ± 2.16 | 15.13 ± 1.97 | 14.58 ± 2.14 |
| Gender (F/M) | 81/129 | 68/40 | 16/33 | 62/79 |
| Estimated IQ | 98.63 ± 16.49 (0.5%) |
99.33 ± 14.15 (0%) |
98.79 ± 12.42 (0%) |
105.13 ± 13.91 (1.4%) |
| Inattention | 7.33 ± 1.71 (0%) |
0.44 ± 1.11 (0%) |
4.34 ± 0.95 (0%) |
0.33 ± 1.11 (0%) |
| Hyperactivity/Impulsiveness | 5.99 ± 1.71 (0%) |
0.34 ± 0.79 (0%) |
2.73 ± 1.96 (0%) |
0.17 ± 0.63 (0%) |
| Maximum digit span forward | 7.94 ± 1.79 (0.5%) |
8.62 ± 1.70 (0%) |
8.80 ± 1.79 (0%) |
8.70 ± 1.68 (1.4%) |
| Maximum digit span backward | 5.10 ± 1.74 (0.5%) |
6.06 ± 1.67 (0%) |
6.06 ± 2.10 (0%) |
6.05 ± 1.94 (1.4%) |
| Stop task errors |
9.45 ± 12.1 (40%) |
5.64 ± 8.02 (36%) |
5.47 ± 4.33 (39%) |
4.47 ± 6.76 (31%) |
| Stop task SSRT | 277.79 ± 76.01 (40.5%) |
256.05 ± 8.02 (36%) |
282.42 ± 58.29 (39%) |
263.14 ± 6.76 (31%) |
| Stop task ICV | 0.22 ± 0.05 (40%) |
0.19 ± 0.04 (36%) |
0.20 ± 0.05 (39%) |
0.18 ± 0.04 (31%) |
| SWM average accuracy | 0.67 ± 0.15 (42%) |
0.68 ± 0.15 (44%) |
0.74 ± 0.11 (31%) |
0.74 ± 0.041 (23%) |
| Scan site 1 | 123 | 52 | 22 | 46 |
| Scan site 2 | 87 | 56 | 27 | 95 |
Note: Values displayed in the table are showed as mean ± standard deviation. Site 1 scanner was AVANTO, and site 2 was SONATA. The percentages in parentheses show the missingness of data in each diagnostic group. Stop task error included N commission and omission errors together. Stop task SSRT: stop task stop signal reaction time. Stop task ICV: interindividual coefficient of variation which is the reaction time variance/mean reaction time. SWM average accuracy: the average accuracy of visuo-spatial working memory task.