Table 1.

Demographic information and primary variables of interest across externalizing and nonexternalizing groups

	Externalizers (N = 32)			Nonexternalizers (N = 32)			Test statistic
	Number of subjects	%		Number of subjects	%		χ2	df	p
Demographics and disorder status
ADHD	4	13		0	0
CD	9	28		0	0
ODD	25	78		0	0
Gender (% female)	24	75		23	72		0.08	1	ns
Race (% White)	19	59		27	84		4.95	1	.03*
	Number of subjects	M	SD	Number of subjects	M	SD	t
Smoking indicators
Age	32	14.94	1.48	32	15.47	1.34	1.50	62	ns
Age at first puff	31	10.10	2.27	26	10.54	2.10	0.76	55	ns
Age at first cigarette	32	10.97	1.98	31	11.61	1.17	1.57	61	ns
Age at daily smoking	31	12.42	1.46	28	12.89	1.26	1.33	57	ns
Age at treatment	31	15.00	1.46	27	15.52	1.28	1.43	56	ns
Cigarettes smoked on first day	32	1.34	0.60	32	1.47	0.72	0.76	62	ns
Cigarettes smoked per day	32	18.66	8.34	32	16.97	5.15	−0.97	62	ns
Years of smoking	32	3.31	1.87	32	2.91	1.42	−0.98	62	ns
Packs of cigarettes per day
Year 1	31	1.08	0.71	31	0.77	0.51	−1.95	60	ns
Year 2	27	1.28	0.74	28	0.98	0.52	−1.73	53	ns
Year 3	15	1.13	0.69	7	0.93	0.35	−0.73	20	ns
Year 4	16	1.63	0.74	11	1.23	0.26	−1.70	25	ns
Externalizing symptoms and behaviors
Externalizing symptoms (CBCL)	32	21.31	11.62	32	13.91	9.70	−2.77	62	ns
Externalizing symptoms (YSR)	32	23.66	9.90	32	15.91	6.20	−3.76	62	.00**
Aggressive behaviors (CBCL)	32	14.34	8.36	32	9.16	6.58	−2.76	62	ns
Aggressive behaviors (YSR)	32	15.53	7.43	32	10.09	4.40	−3.56	62	.01**
Delinquent behaviors (CBCL)	32	6.97	4.01	32	4.75	3.76	−2.28	62	.03*
Delinquent behaviors (YSR)	32	8.13	3.42	32	5.81	2.66	−3.02	62	.04*
Self-reported measures of dependency
Fagerström Test for Nicotine Dependence	32	7.28	1.42	29	6.86	1.06	−1.30	59	ns
Motivation to quit	32	8.89	1.37	32	8.38	1.50	−1.44	62	ns

Note. ADHD, attention-deficit/hyperactivity disorder; CD, conduct disorder; ODD, oppositional defiant disorder; CBCL, Child Behavior Checklist; and YSR, Youth Self-Report.

*p < .05; **p < .01. All test statistics were nonsignificant (ns, p > .05).