TABLE 3.

Comparison of Age at PHV and Magnitude of PHV Between ADHD Cases and Non-ADHD Controls and by Cumulative Stimulant Duration

		No. of Subjects	Age at PHV (y)		Magnitude of PHV (cm/y)
			Mean (SD)	Pa	Mean (SD)	Pa
Male subjects	ADHD cases	158	13.3 (1.1)	.96	8.2 (1.5)	.71
	Non-ADHD controls	256	13.3 (1.3)		8.3 (1.6)
Female subjects	ADHD cases	59	11.0 (1.4)	.87	7.5 (1.4)	.80
	Non-ADHD controls	87	11.0 (1.1)		7.4 (1.2)
ADHD cases only	Cumulative stimulant duration before PHV
Male subjects	Stimulant naiveb	65	12.9 (1.2)	.002	8.0 (1.5)	.22
	Stimulant treatedc	88	13.5 (1.0)		8.3 (1.5)
	3 m–3 y	27	13.3 (0.9)		8.4 (1.8)
	≥3 y	61	13.6 (0.9)		8.3 (1.5)
Female subjects	Stimulant naiveb	36	10.8 (1.5)	.36	7.5 (1.5)	.99
	Stimulant treatedc	22	11.2 (1.0)		7.5 (1.4)
	3 m–3 y	16	11.1 (1.1)		7.4 (1.4)
	≥3 y	6	11.3 (0.9)		7.7 (1.5)

^a2-sample t test comparing ADHD cases with non-ADHD controls and, among the ADHD cases, stimulant naive with stimulant treated.

^bStimulant naive was defined as subjects on stimulants for <3 mo before the time of the PHV.

^c6 ADHD cases had an unknown duration of stimulant medication treatment and were not included in this subanalysis.