Table 4.

Covariate and control effects in logistic regressions

Variable	Current smoking	Current drinking	Heavy episodic drinkinga	Marijuana useb
Age(ref.: 17-18 years)
19-20 years	1.17 [0.81, 1.67]	1.90* [1.43, 2.54]	2.30* [1.57, 3.37]	1.16 [0.85, 1.59]
21-22 years	1.26 [0.74, 2.14]	4.41* [2.73, 7.12]	3.22* [1.81, 5.73]	1.39 [0.84, 2.31]
≥23 years	0.75 [0.25, 2.30]	2.13† [0.90, 5.03]	7.90* [2.92, 21.38]	2.35 [0.81, 6.81]
Non-White (ref.: White)	0.32* [0.21, 0.49]	0.43* [0.30, 0.60]	0.19* [0.11, 0.32]	0.47* [0.32, 0.71]
Female (ref.: male)	0.69* [0.47, 0.99]	0.58* [0.43, 0.79]	0.53* [0.37, 0.76]	0.57* [0.40, 0.79]
Family background
Parents married in 1997 (ref.: unmarried)	1.00 [0.65, 1.53]	1.26 [0.89, 1.77]	2.10* [1.29,3.42]	1.37 [0.92, 2.02]
Parental age in 1997 (ref.: <age 36)
36-49 years	0.86 [0.57, 1.30]	1.31 [0.91, 1.87]	0.93 [0.59, 1.46]	1.10 [0.74, 1.63]
≥50 years	1.44 [0.62, 3.35]	0.95 [0.53, 1.70]	0.73 [0.33, 1.63]	1.42 [0.73, 2.78]
High school graduate (ref.: nongraduates)	0.27* [0.16, 0.46]	1.06 [0.62, 1.82]	1.10 [0.52, 2.34]	0.65† [0.40, 1.06]
Educational and working status (ref.: not working or in school)
Working only	0.83 [0.55, 1.25]	1.21 [0.79, 1.84]	1.08 [0.57, 2.04]	0.99 [0.64, 1.54]
Student	0.32* [0.20, 0.50]	0.96 [0.63, 1.47]	1.26 [0.66, 2.42]	0.68 [0.42, 1.08]
Residence and relationship status
Lives with parents (ref.: lives on own)	0.84 [0.58, 1.21]	0.76 [0.54, 1.06]	0.63* [0.43, 0.92]	0.93 [0.66, 1.31]
Married (ref.: neither married nor cohabiting)	0.74 [0.31, 1.77]	0.54† [0.26, 1.10]	0.41 [0.12, 1.41]	0.26* [0.09, 0.74]
Cohabiting (ref.: neither married nor cohabiting)	1.77* [1.07, 2.93]	0.91 [0.56, 1.49]	0.56* [0.32, 0.98]	1.04 [0.64, 1.68]
Ever been pregnant/fathered a child (ref.: never pregnant/fathered)	1.57† [0.93, 2.65]	0.72 [0.45, 1.16]	0.68 [0.32, 1.46]	0.66 [0.38, 1.15]
Year 2005 (ref.: Year 2007)	1.00 [0.74, 1.37]	1.41* [1.07, 1.85]	2.07* [1.45, 2.97]	1.35* [1.03, 1.77]
Constant	2.61* [1.12, 6.06]	1.41 [0.63, 3.13]	0.13* [0.05, 0.34]	0.72 [0.31, 1.64]
Pseudo R2	.1444	.0969	.1474	.0605
Sample size, n	1,853	1,853	1,853	1,853

Notes: Odds ratios and 95% confidence intervals [reported in brackets] are shown. Ref. = reference.

^aAt least four drinks (for females) or five drinks (for males) per occasion, 12 or more times per year

^breference period is the 12 months before the interview.

^†p < .10

^*p < .05.