TABLE 7.

Results from t-tests for gender differences.

Scale	Gender	Controls				SDIs
		M	SD	t/p	Effect size	M	SD	t/p	Effect size
Brinkley total score	Male	23.62	9.69	3.25/0.001	0.38	30.07	10.35	4.80/0.001	0.62
	Female	20.00	9.25			23.83	9.72
Brinkley egocentric	Male	9.39	5.65	5.18/0.001	0.59	11.22	5.76	4.58/0.001	0.59
	Female	6.41	4.25			7.94	5.16
Brinkley antisocial	Male	4.41	2.89	−2.28/0.023	0.27	6.85	3.14	0.52/0.602	0.07
	Female	5.22	3.14			6.65	2.66
Brinkley callous	Male	2.95	2.87	3.37/0.001	0.38	3.81	2.39	4.70/0.001	0.60
	Female	1.97	2.15			2.43	1.98

SDIs, substance dependent individuals. Effect sizes were calculated following Cohen’s (1994) formulas.