Table 2.

Primary analysis: Independent predictors for self-directed aggressive behavior

Variable	Controls N=557	Suicide attempters/self-mutilators N=145	L-R χ2	P	FDR p
BGHA	33.9±10.1	43.4±12.3	12.6	0.0004	0.001
Violent behavior in jail			8.1	0.004	0.007
Extraversion	14.1±3.4	12.48±3.7	6.2	0.013	0.015
5-HTTLPR			7.7	0.02	0.02
CTQ total continuous score	37.6±10.5	47.1±18.2	9.9	0.002	0.004
HDRS	6.2±5.5	11.56±7.6	17.7	<0.0001	0.0004
Axis I disorders			6.2	0.013	0.015
Whole model			162.8	<0.0001	0.0004
Whole model variance, df			0.23, 8

± Standard deviation

L-R χ² = Likelihood Ratio chi square; df = degrees of freedom

5-HTTLPR H v I v L: high activity variant vs intermediate activity variant vs low activity variant

Extraversion scores derive from the Eysenck Personality Questionnaire

BGHA- Brown-Goodwin History of Aggression

HDRS- Hamilton Depression Rating Scale

CTQ- Childhood Trauma Questionnaire

Axis I psychiatric disorders- DSM IV criteria

The variance inflation factor (VIF) for each of the independent variables ranged from 1.1 to 1.5, indicating that the model is stable.