. Author manuscript; available in PMC: 2019 Feb 1.

Published in final edited form as: Addiction. 2017 Sep 25;113(2):325–333. doi: 10.1111/add.14013

Table 2.

Detailed path analysis results for main model^a.

Path	β	95% CI	p-value
Autoregressive relationships
Prior smoking freq. to later smoking freq.	0.604	0.56 – 0.640.58	<.001
Prior NDSS to later NDSS	0.629	−0.67	<.001
Prior e-cigarette freq. to later e-cigarette freq.	0.120	0.08 – 0.16	<.001

Determinants of nicotine dependence
Prior smoking freq. to later NDSS	0.139	0.10 – 0.18	<.001
Prior e-cigarette freq. to later NDSS	0.005	−0.02 – 0.03	.693

Effects of nicotine dependence
Prior NDSS to later smoking freq.	0.169	0.13 – 0.21	<.001
Prior NDSS to later e-cigarette freq.	0.069	0.00 – 0.13	.039

Dual-use relationship
Prior smoking freq. to later e-cigarette freq.	0.118	0.06 – 0.18	<.001
Prior e-cigarette freq. to later smoking freq.	0.021	−0.00 – 0.04	.081

For each relationship category (rows) and individual type of path (sub-rows), the standardized coefficient (β), 95% confidence interval (CI), and p-value are shown based on the main model in Figure 2 (all equivalent paths are constrained to be equal across consecutive pairs of time waves). NDSS: Nicotine Dependence Syndrome Scale score. Bold: p<.05