BACKGROUND: To examine the prevalence and patterns of recent electronic cigarette (e-cigarette) use in a nationally representative sample of US adults and adolescents. METHODS AND RESULTS: Using tobacco information from NHANES (National Health and Nutrition Examination Survey) 2013-2014, 5423 adults and 895 adolescents (aged 13-17 years) were included in this analysis. Demographic, tobacco use, and drug use information were self-reported. Recent e-cigarette use (within the previous 5 days) was stratified by smoking status. Of 125 e-cigarette users, 116 participants were aged ≥18 years, corresponding to 2.6% (95% confidence interval [CI], 2.0-3.1) and 1.21% (95% CI, 0.3-2.1) prevalence of e-cigarette use among US adults and adolescents, res...