Table 5.

Univariate General Linear Models Simultaneously Between Standardized Dependence Measures and Outcomes of Interest, With Overlapping Variables Excluded From Dependence Measures, Including Change in Adjusted R² Compared With Covariate-Only Regression Models^a

	t	${\eta }_p^2$
	Vaping frequency (times per month)
	n = 1099
	Adj R2 = 0.4968	Change in R2 = 0.0675
PS-ECDI	11.65	0.111***
EDS	−1.17	0.001
Self-perceived	7.40	0.048***
Time from waking	7.73	0.052***
Sex	0.65	0.000
Age	2.44	0.005*
Race	0.27	0.000
Smoking status	5.76	0.030***
Other tobacco product	0.26	0.000
	Vaping frequency (times per weekend day)
	n = 1114
	Adj R2 = 0.4465	Change in R2 = 0.1175
PS-ECDI	−2.98	0.008**
EDS	7.33	0.047***
Self-perceived	6.47	0.037***
Time from waking	7.25	0.046***
Sex	−0.69	0.000
Age	0.57	0.000
Race	0.85	0.001
Smoking status	−0.29	0.000
Other tobacco product	−1.04	0.001
	Vaping frequency (times per weekday)
	n = 1114
	Adj R2 = 0.4787	Change in R2 = 0.0856
PS-ECDI	−2.76	0.007**
EDS	8.03	0.055***
Self-perceived	6.74	0.040***
Time from waking	7.66	0.050***
Sex	−1.06	0.001
Age	0.39	0.000
Race	1.05	0.001
Smoking status	−1.44	0.002
Other tobacco product	0.25	0.000
	Nicotine concentration among nicotine users
	n = 1009
	Adj R2 = 0.2123	Change in R2 = 0.3520
PS-ECDI	1.55	0.002
EDS	−1.18	0.001
	Nicotine concentration among nicotine users
	n = 1009
	Adj R2 = 0.2123	Change in R2 = 0.3520
Self-perceived	3.16	0.010**
Time from waking	4.14	0.017***
Sex	−2.87	0.008**
Age	−12.77	0.140***
Race	−0.06	0.000
Smoking status	1.17	0.001
Other tobacco product	0.47	0.000

EDS = E-Cigarette Dependence Scale; PS-ECDI = Penn State Electronic Cigarette Dependence Index.

^aVariation in Ns due to responses missing at random.

*p < .05.

^**  p < .01.

^***  p < .001.