Table 3.

Adjusted logistic regression of susceptibility to each product at baseline on ever use at 6 months, 12 months, and 18 months among never users at baseline (n = 2844; N = 318,097 at baseline).

Variable		Ever use at 6 months			Ever use at 12 months			Ever use at 18 months
		OR	95% CI	p-Value	OR	95% CI	p-Value	OR	95% CI	p-Value
E-cigarettes
Sex (ref: female)	Male	1.30	0.61–2.76	0.488	1.08	0.73–1.61	0.700	1.31	0.88–1.96	0.185
Age		1.46	1.17–1.82	0.001	1.55	1.31–1.84	<0.001	1.33	1.08–1.64	0.008
Family SES (ref: middle)	High	1.65	0.55–4.98	0.368	1.00	0.45–2.20	0.993	1.24	0.63–2.44	0.521
	Low	0.64	0.22–1.89	0.412	0.45	0.18–1.12	0.085	0.83	0.33–2.07	0.682
Ethnicity (ref: non-Hispanic)	Hispanic	1.29	0.60–2.76	0.599	0.99	0.60–1.63	0.966	0.93	0.60–1.44	0.740
Susceptible to e-cigarettes (ref: no)	Yes	6.64	3.39–13.00	<0.001	5.01	2.69–9.34	<0.001	2.88	1.66–4.97	<0.001
Any combustible product
Sex (ref: female)	Male	0.85	0.33–2.15	0.725	0.97	0.50–1.89	0.920	1.05	0.59–1.87	0.867
Age		1.18	0.88–1.59	0.267	1.33	1.09–1.62	0.005	1.34	1.16–1.54	<0.001
Family SES (ref: middle)	High	0.54	0.10–2.81	0.458	1.17	0.58–2.38	0.662	1.30	0.74–2.26	0.356
	Low	1.08	0.29–4.03	0.904	1.21	0.49–3.03	0.673	1.19	0.59–2.43	0.620
Ethnicity (ref: non-Hispanic)	Hispanic	0.74	0.27–2.14	0.575	0.97	0.48–1.95	0.930	0.99	0.61–1.63	0.983
Susceptible to any combustible (ref: no)	Yes	5.20	1.92–14.07	0.001	3.89	2.17–6.95	<0.001	3.38	2.03–5.62	<0.001

Note: OR = odds ratio, CI = confidence interval, SES = socioeconomic status. “Any combustible” includes cigarettes, cigars, and hookah.