Table 2.

Zero-order Correlations of Focal Variables at the Cross-sectional and Longitudinal Levels

	Cross-sectional				Longitudinal
	1 (T1)	2 (T1)	3 (T1)	4 (T1)	1 (T2)	2 (T2)	3 (T2)	4 (T2)
1 – Media scanning (T1)	--				.31	.23	.15	.11
2 – Interpersonal communication (T1)	.50	--			.21	.26	.18	.15
3 – Descriptive norm perceptions (T1)	.17	.23	--		.12	.18	.55	.28
4 – E-cigarette use behavior (T1)	.11	.20	.31	--	.04	.08	.22	.41

Note. The correlations were calculated based on the weighted sample, smallest n = 10,592 for the cross-sectional sample and smallest n = 3,186 for the longitudinal sample. Pairwise Pearson’s correlation coefficients are presented. All correlation coefficients at the cross-sectional level presented in the table are significant at p < .001. Nearly all correlation coefficients at the longitudinal level presented in the table are significant at p < .01, except for the correlation between T1 behavior and T2 scanning (p = .07).