Associations between e-cigarette pack size and vaping frequency among U.S. adults.

Little research exists on the association between e-cigarette pack quantity and use. We examined whether using e-cigarettes every day or somedays was associated with purchasing e-cigarettes by the box/pack or as singles. Data are from the 2018-2019 Tobacco Use Supplement to the Current Population Survey, analyzed in 2020. The sample included adults who reported current e-cigarette use (N=2,413). We conducted multivariable logistic regression models to examine the association between purchasing e-cigarettes by the box/pack or as singles and using e-cigarettes every day or somedays. Models controlled for demographic characteristics, flavored e-cigarette use, and other tobacco use, and were stratified by sex and device type. Of the 2,413 respondents, 63.1% reported purchasing e-cigarettes as singles, while 36.9% reported buying by the box or pack. Among those who purchased by the box and singles, approximately 56% and 50% used e-cigarettes every day, respectively. Those who reported purchasing by the box/pack had greater odds of every day e-cigarette use compared to some day use (Adjusted Odds Ratio: 1.36, 95% CI: 1.09, 1.68). This finding held for both males, females, and all device types. These findings present a first step in determining the relationship between e-cigarette pack size and use behavior.