Table 1.

Variables in E-Cigarette Impact Simulations^a

Variable	Value(s)
1. Overall background smoking cessation rate (independent of vaping)	4.35%
2. Background smoking initiation rate (independent of vaping)	7.8%
3. Ease of quitting smoking without vaping	• Harder than average difficulty (25% of smokers; 2.18% background quit rate) • Average difficulty (50% of smokers; 4.35% background quit rate) • Easier than average difficulty (25% of smokers; 6.53% background quit rate)
4. Impact of vaping on smoking cessation rate	Increase background rate by 10%, 25%, 50%, 100%, or 200%
5. Impact of vaping on smoking initiation rate	Increase the background rate by 0% or 10%
6. Health risk of vaping compared to smoking	Reduces former smokers’ annual mortality-reduction benefit (compared to continued smoking) by 0%, 5%, 10%, or 20%
7. Vaping most assists which types of smokers in quitting smoking	Values vary depending on overall impact of vaping on the smoking cessation rate; see text
8. Relationship between smoking cessation rate (without vaping) and age	Rate rises with age, constant across ages, or falls with age

^aSee text for explanation of variables and their values.