Materials and methods: Twenty smoke

Materials and methods: Twenty smokers (11 female, aged 31±10, CPD 16±8, FTND 4±3, and exhaled CO 16±
17 (mean ± SD)) who were naïve to e-cigarettes participated in this study. They were asked to substitute their
regular tobacco cigarettes with first generation e-cigarettes (labeled 18 mg nicotine) for two weeks. Puffing
topography (number of puffs, puff volume, intervals between puffs, and average puff flow rate) was measured
at the initial use (baseline), as well as after one and two weeks of product use. We tested changes in puffing
topography outcomes using repeated measures ANOVA.