. Author manuscript; available in PMC: 2010 Jan 15.

Published in final edited form as: J Am Acad Child Adolesc Psychiatry. 2008 Dec;47(12):1375–1383. doi: 10.1097/chi.0b013e3181893620

TABLE 4.

Comparison of Pretreatment and Terminal Cytogenetic Damage End-points Between MPH and MAS Groups

		MAS	MPH	MAS vs. MPH
Sample	Measure	Mean (SE)	Mean (SE)	Mann-Whitney U test statistic (n_MAS, n_MPH)^a	p^b
Baseline	% cells with CA	0.43 (0.13)	0.48 (0.09)	485.0 (22, 25)	.33
	Mean SCE/cell	5.17 (0.36)	4.70 (0.36)	533.5 (21, 25)	.38
	% MN/BN cells	1.22 (0.21)	1.20 (0.17)	309.0 (17, 20)	.68
Terminal	% cells with CA	0.46 (0.09)	0.46 (0.09)	527.5 (22, 25)	1.00
	Mean SCE/cell	4.41 (0.33)	4.83 (0.24)	423.0 (21, 25)	.12
	% MN/BN cells	1.04 (0.09)	0.96 (0.10)	461.5 (20, 24)	.80

Note: CA = chromosomal aberration; SCE = sister chromatid exchanges; MN/BN = micronucleated binucleate; SE = standard error; MAS = mixed amphetamine salts; MPH = methylphenidate.

n, number of subjects analyzed for the endpoint.

Two-sided p values.