“…E-cigarette experimentation and use have been associated among youth with susceptibility to conventional cigarette smoking initiation [6,9], conventional cigarette smoking [4,5,8,10,11,12,13,14,15,16,17], male gender [4,8,12,13,15], ever-use of other tobacco (combustible and non-combustible) [10,11,13], alcohol use [4,8,13,17], perception of low harm of e-cigarettes [18,19,20,21], peer smoking behavior [4,12,17,20], parents’ smoking [20,22], peer e-cigarette use [23] and exposure to e-cigarette advertising [24,25]. Socioeconomic factors have been studied less, and their association with e-cigarette use is not so clear.…”