“…To address the first aim of this study, we created an e-cigarette topics dictionary using the software package Quanteda (Welbers, Van Atteveldt, & Benoit, 2017). This dictionary categorized Reddit submissions based on seven different e-cigarette-related topics: (1) "advice," which refers to submissions about seeking information; (2) "build your own," which refers to submissions about e-cigarette parts or kits that can be used to build vaping devices; (3) "buying/selling," which refers to submissions about e-cigarettes as merchandise; (4) "drugs," which refers to submissions about the use of vaping devices for illicit purposes, such as vaping marijuana; (5) "e-juice," which refers to submissions about e-liquid or e-liquid flavors; (6) "health/safety," which refers to submissions about the various health effects associated with e-cigarettes; and (g) "tobacco," which refers to submissions containing tobacco-related content, including mentions of combustible cigarettes or nicotine.…”