TABLE 3.
Use of E-cigarettes, Cigarettes, or Dual Product Use at Baseline and Odds of Past-30-Day Use at Follow-up
| Baseline Product Use | Past-30-d Use at Follow-up | ||
|---|---|---|---|
| Exclusively E-cigarettes Versus None, OR (95% CI) | Exclusively Cigarettes Versus None, OR (95% CI) | Dual Use Versus None, OR (95% CI) | |
| Past-30-d usea,b,c | |||
| Neither product | Reference | Reference | Reference |
| Exclusively e-cigarettes | 7.28 (4.86–10.9)d | 3.84 (1.80–8.19)d | 8.86 (5.08–15.4)d |
| Exclusively cigarettes | 4.03 (1.30–12.6)d | 29.5 (12.3–70.8)e | 28.8 (12.6–66.1)e |
| Dual product | 11.3 (5.51–23.2)d | 44.3 (20.4–96.1)e | 105 (56.6–194)f |
Superscript letters denote a test of independence of effect estimates by row; estimates sharing letters are not statistically significantly different from one another (P < .05).
a
Stability estimates of remaining in a use pattern (versus nonuse) on the diagonal.
b
Adjusted for gender, race and/or ethnicity, grade, and study with a random effect for school.
c
Restricted to the CHS and YASS.