Table 4.

Parameter Estimates of Hierarchical Regression Analyses of the Drug and Alcohol Factor

Parameter	Model
	1		2		3		4		5
	Parameter estimate	SE	Parameter estimate	SE	Parameter estimate	SE	Parameter estimate	SE	Parameter estimate	SE
Random effects (variance components)
Individual (σ2)	0.81*	0.03	0.75*	0.03	0.75*	0.03	0.75*	0.03	0.75*	0.03
Nuclear-family level ( ${\tau }_{\pi }^2$)	0.18*	0.04	0.18*	0.04	0.18*	0.04	0.18*	0.04	0.16*	0.02
Twin-family level ( ${\tau }_{\beta }^2$)	0.01	0.03	0.01	0.03	0.00	0.03	0.00	0.03	0.00	0.03
Fixed effects
Intercept (γ000)	0.00	0.02	−0.38	0.37	−0.36	0.38	−0.37	0.37	−0.51	0.44
Divorce (before the age of 16)
Parental divorce (β01t)			0.32*	0.06
Between-families (γ001)					0.31*	0.07	0.31*	0.07	0.18*	0.07
Within-family (β02t)					0.28*	0.08
Within-family MZ (γ010)							0.40*	0.11	0.37*	0.11
Within-family DZ–MZ (γ001)							−0.20	0.15	−0.21	0.15
Level 1 variables
Age (π1nt)			0.03	0.03	0.02	0.03	0.02	0.03	0.04	0.03
Age2 (π2nt)			0.00	0.01	0.00	0.01	0.00	0.01	0.00	0.01
Gender (π3nt)			0.41*	0.04	0.41*	0.04	0.41*	0.04	0.41*	0.04
Twin type (γ002)							−0.03	0.04	−0.04	0.04
Parental characteristics: Maternal
Conduct (β03t)									0.11*	0.03
Alcohol abuse (β04t)									0.11*	0.04
Depression (β05t)									0.02*	0.01
Drug use (β06t)									−0.01	0.07
Smoking (β07t)									0.10*	0.05
Suicidality (β07t)									0.01	0.03
Education (β08t)									0.00	0.02
Age at first birth (β09t)									0.01	0.01
Parental characteristics: Paternal
Conduct (β010t)									0.06*	0.02
Alcohol abuse (β011t)									0.03	0.05
Depression (β012t)									0.00	0.01
Drug use (β013t)									0.08	0.07
Smoking (β014t)									0.05	0.06
Suicidality (β015t)									0.00	0.04
Education (β016t)									0.02	0.02
Age at first birth (β017t)									0.00	0.01

Note. MZ = monozygotic; DZ = dizygotic.

^*p < .05.