Table 1.

Comparisons between control and antisocial personality disorder groups on demographic, cognitive, trauma and antisocial measures

	Control group (n = 69)				Antisocial personality disorder group (n = 18)
	% (n)	Mean	s.d.	Range	% (n)	Mean	s.d.	Range	Statistic	P
Demographics
Age, years		31.23	6.83	21–46		32.72	6.54	24–44	t = 0.82	0.41
Social class		35.00	10.84	17–58		33.83	7.64	16–43	t = 1.0	0.32
Ethnicity, White	56.17 (36)				33.33 (6)				χ2 = 2.95	0.11
Gender, male	84.1 (58)				94.4 (17)				χ2 = 1.52	0.22
Cognitive
Total IQ		99.49	15.91	66–134		98.44	12.12	78–118	t = 0.8	0.41
Trauma
Number of head injuries		2.22	4.47	0–25		2.23	3.01	0–12	χ2 = 0.6	0.73
Traumatic stress		2.29	5.29	0–28		2.72	5.89	0–20	t = –0.27	0.78
Antisocial
Psychopathy Checklist–Revised
Total scores		15.88	6.43	5–30		28.65	6.12	21–40	t = 14.8	0.0001
Factor 1		5.32	3.52	0–16		10.05	3.56	4–16	t = 8.4	0.0001
Factor 2		7.15	2.97	0–15		13.70	2.91	9–18	t = 9.2	0.0001
Antisocial personality disorder score		4.31	2.64	0–10		10.50	2.28	6–14	t = 12.7	0.0001
Charges		2.86	10.03	0–53		6.94	6.52	0–20	t = –1.61	0.11
Convictions		0.94	3.58	0–22		2.44	2.50	0–9	t = –1.65	0.10