Table 3.

BRIEF outcomes

	Placebo, M (SE)	Methylphenidate, M (SE)	t (df)	d
BRIEF parent report (T score)
	65.20 (1.30)	60.05 (1.30)	4.10 (18)***	0.97
1	64.49 (1.84)	61.61 (1.84)	1.10 (26.5)	0.21
2	65.91 (1.84)	58.49 (1.84)	2.85 (26.5)**	0.55
BRI – overall	58.00 (1.33)	54.30 (1.33)	2.44 (18)*	0.57
	57.29 (1.88)	55.51 (1.88)	0.67 (30.6)	0.12
	58.71 (1.88)	53.9 (1.88)	2.11 (30.6)*	0.38
	67.75 (1.52)	62.40 (1.52)	3.79 (18)**	0.89
	67.18 (2.15)	63.82 (2.15)	1.11 (25.8)	0.22
	68.32 (2.15)	60.98 (2.15)	2.42 (25.8)*	0.48
BRIEF self report (T score)
GEC – overall	46.03 (3.53)	41.10 (3.53)	2.71 (7.0)*	1.02
BRI – overall	44.85 (3.31)	41.33 (3.31)	2.10 (7.0)	0.79
MI – overall	47.46 (3.52)	41.81 (3.52)	3.09 (7.0)*	1.17

^*p< .05

^**p< .01

^***p< .0001, BRI = Behavioral regulation index, GEC = Global executive composite, and MI = Metacognitive index. Individual period results are not given for the self report measures because the treatment-by-period interaction terms were not statistically significant.

Note: “period 1” refers to the first 4 weeks of the study, and “period 2” refers to the final 4 weeks after cross-over.