Am J Prev Med

IntroductionAccounting for occasional or intermittent e-cigarette use has yielded higher estimates of current use among U.S. adults. However, frequency of e-cigarette use by population subgroups is not well described. This study assessed e-cigarette use frequency by sociodemographic characteristics and other tobacco product use among U.S. adults.MethodsThis study analyzed combined data from the 2012\u20132013 (n = 60,192) and 2013\u20132014 (n=75,233) National Adult Tobacco Survey, a telephone-based survey of U.S. adults aged 6518 years, to assess frequency of e-cigarette use (daily, some days, rarely) by sex, age, race/ethnicity, education, annual household income, U.S. region, marital status, sexual orientation, and cigarette smoking and other tobacco product use (cigars, cigarillos, little filtered cigars; traditional pipes; water pipes; and chewing tobacco, snuff, dip, snus, and dissolvable tobacco products). Analyses took place in 2016.ResultsAmong current e-cigarette users, 19.3% used daily, 29.3% used some days, and 51.4% used rarely. Daily use was lowest among younger adults, Hispanics, and those who were single, never married, or not living with a partner; and greatest among non-Hispanic Asians (p