Table 4.

Logistic regression analyses of predictors of use of tobacco, alcohol, marijuana and other illicit drugs.

	Block 1 – Age		Block 2 – Externalizing problems		Block 3 – ADHD symptoms
	OR	95% CI	OR	95% CI	OR	95% CI
Alcohol
Constant	0†		0†		0
Age	1.44	0.92-2.28	1.34	0.82-2.18	1.35	0.81-2.24
Inattention			0.95	0.87-1.03	0.95	0.87-1.04
Hyperactivity/Imp.			1.07	0.99-1.15	1.05	0.97-1.14
ODD					1.05	0.82-1.35
Conduct Disorder					1.06	0.80-1.41
Nagelkerke R2	0.080		0.18		.21
Tobacco
Constant	0*		0†		0†
Age	1.69†	0.98-2.92	1.67†	0.96-2.92	1.58	0.08-2.91
Inattention			1	0.94-1.08	1.01	0.93-1.09
Hyperactivity/Imp.			1	0.94-1.07	0.98	0.91-1.05
ODD					1.18	0.91-1.53
Conduct Disorder					1.11	0.86-1.42
Nagelkerke R2	0.127		0.128		0.31
Marijuana
Constant	0*		0*		0*
Age	1.90*	1.03-3.53	1.82†	0.83-3.56	1.68	0.79-3.59
Inattention			1.06	0.98-1.15	1.09†	0.99-1.19
Hyperactivity /Imp.			1.01	0.95-1.07	0.98	0.92-1.06
ODD					0.93	0.71-1.21
Conduct Disorder					1.45*	1.02-2.07
Nagelkerke R2	0.162		0.24		0.44
Other illegal drugs
Constant	0.42		0.09		4811.88
Age	0.97	0.56-1.66	0.89	0.51-1.56	0.51	0.20-1.30
Inattention			1.05	0.95-1.16	1.05	0.94-1.16
Hyperactivity/Imp.			0.99	0.92-1.07	0.96	0.86-1.06
ODD					0.77	0.55-1.09
Conduct Disorder					1.95**	1.20-3.16
Nagelkerke R2	0.001		0.04		0.49

Note. ODD = Oppositional defiant disorder; CI = confidence interval; OR = odds ratio. † < .10; * p < .05; ** p < .010.