Table 1.

Clinical and demographic characteristics of patients with ADHD (N=110) and typically developing controls (N=142) at each timepoint of the study.

Characteristic	ADHD (N=110)			TD (N=142)			Test of significance
	N	%		N	%
Female	28	25.45%		61	42.96		χ2=8.31, p=0.004
N
Time 1	110	100%		142	100%		-
Time 2	54	49.09%		87	61.27%		-
Time 3	19	17.27%		53	37.32%		-
Time 4	9	8.1%		33	23.24%		-
Time 5	4	3.6%		15	10.56%		-
	Mean	SD	Range	Mean	SD	Range
Age, y
Time 1	10.83	2.2	6–16	10.49	2.81	6–17	t(250)=1.04, p=0.3
Time 2	12.34	2.35	7–17	11.89	2.54	7–16	t(139)=1.05, p=0.29
Time 3	13.45	2.27	10–17	13.15	2.45	8–17	t(70)=0.47, p=0.64
Time 4	14.03	2.12	11–17	14.07	2.14	9–17	t(40)=0.05, p=0.96
Time 5	14.48	2.19	12–17	15.16	1.4	13–17	t(19)=0.77, p=0.45
ADHD symptoms
Time 1	11.35	3.42	3–18	0.25	0.7	0–3	t(250)=37.69, p<0.001
Time 2	10.2	3.43	2–18	0.24	0.61	0–3	t(139)=26.47, p<0.001
Time 3	10.63	3.62	4–17	0.13	0.44	0–2	t(70)=20.95, p<0.001
Time 4	10.11	2.71	5–13	0.18	0.64	0–3	t(40)=19.7, p<0.001
Time 5	11.75	1.71	10–14	0.2	0.41	0–1	t(19)=25.37, p<0.001
ADHD treatment response (%)
Time 1	69.92%	0.27	0–100%	-	-	-	-
Time 2	67.79%	0.24	11–100%	-	-	-	-
Time 3	69.02%	0.24	33–100%	-	-	-	-
Time 4	70.1%	0.24	33–100%	-	-	-	-
Time 5	61.24%	0.23	35–91%	-	-	-	-
Dosage (daily methylphenidate-equivalent mg/kg)
Time 1	0.82	0.46	0.15–2.25	-	-	-	-
Time 2	0.86	0.43	0.14–2.04	-	-	-	-
Time 3	0.88	0.36	0.5–1.86	-	-	-	-
Time 4	0.86	0.33	0.27–1.31	-	-	-	-
Time 5	0.88	0.2	0.66–1.1	-	-	-	-

Abbreviations: ADHD, attention-deficit/hyperactivity disorder; mg/kg, milligram per kilogram; TD, typically developing; y, years.