Table 1.

Descriptive statistics for the ADHD and TD groups across the two cohorts. Within each cohort, the two groups were matched on age, gender, handedness, IQ and head motion during fMRI.

	Primary cohort			Replication cohort
	TD (N=40)	AD (N=40)	p	TD (N=30)	AD (N=30)	p
Age	11.9(3.2)	11.7(2.9)	0.66	12.3(1.5)	12.6(2.1)	0.47
Gender (female/male)	17/23	13/27	0.36	0/30	0/30	1.00
Handedness scores	0.6(0.3)	0.6(0.3)	0.84	0.9(0.2)	1(0)	0.33
IQ	111(15)	107(14)	0.26	113(10)	113(9)	1.00
Inattention	45(5)	71(9)	0.00	15(3)	28(4)	0.00
Hyperactivity/Impulsivity	46(5)	66(12)	0.00	12(4)	23(7)	0.00
Head Motion
Range
X (mm)	0.307(0.194)	0.324(0.203)	0.71	0.271(0.161)	0.241(0.135)	0.44
Y (mm)	0.545(0.392)	0.676(0.5)	0.19	0.596(0.301)	0.563(0.333)	0.69
Z (mm)	0.555(0.309)	0.667(0.346)	0.13	0.884(0.498)	0.922(0.458)	0.76
Pitch (deg)	0.012(0.007)	0.014(0.009)	0.27	0.013(0.007)	0.015(0.008)	0.56
Roll (deg)	0.006(0.003)	0.006(0.004)	0.43	0.007(0.004)	0.008(0.005)	0.74
Yaw (deg)	0.007(0.003)	0.007(0.002)	0.65	0.006(0.005)	0.006(0.003)	0.72
RMS
X (mm)	0.093(0.064)	0.091(0.092)	0.92	0.097(0.082)	0.093(0.079)	0.86
Y (mm)	0.217(0.178)	0.235(0.192)	0.66	0.257(0.149)	0.198(0.124)	0.10
Z (mm)	0.196(0.137)	0.247(0.198)	0.19	0.341(0.222)	0.324(0.225)	0.77
Pitch (deg)	0.005(0.003)	0.005(0.003)	0.64	0.005(0.004)	0.005(0.004)	0.56
Roll (deg)	0.002(0.001)	0.002(0.002)	0.65	0.002(0.002)	0.003(0.002)	0.34
Yaw (deg)	0.003(0.002)	0.003(0.002)	0.46	0.003(0.003)	0.002(0.002)	0.57
Scan to Scan motion (mm)	0.08(0.036)	0.092(0.04)	0.16	0.082(0.033)	0.093(0.039)	0.25

^*The Conners’ Parent Rating Scale-Revised, Long Version and the ADHD Rating Scale were used as dimensional measures of ADHD symptoms in the Primary and Replication cohorts, respectively. Note that Inattention and hyperactivity/impulsivity scores are raw scores provided by ADHD200 Consortium. Handedness scores: 1, right-handed; 0, left-handed.