title: Ever Use of Nicotine and Nonnicotine Electronic Cigarettes Among High School Students in Ontario, Canada.
abstract: BACKGROUND
  There are limited data on the use of electronic cigarettes (e-cigarettes) among youth, particularly with regard to the use of nicotine versus nonnicotine products. This study investigates ever use of nicotine and nonnicotine e-cigarettes and examines the demographic and behavioral correlates of e-cigarette use in Ontario, Canada.
  
  
  METHODS
  Data for 2,892 high school students were derived from the 2013 Ontario Student Drug Use and Health Survey. This province-wide school-based survey is based on a 2-stage cluster design. Bivariate and multivariate analyses were used to investigate the factors associated with ever use of e-cigarettes. Ever use of e-cigarettes was derived from the question, "Have you ever smoked at least one puff from an electronic cigarette?" All analyses included appropriate adjustments for the complex study design.
  
  
  RESULTS
  Fifteen percent of high school students reported using e-cigarettes in their lifetime. Most students who ever used e-cigarettes reported using e-cigarettes without nicotine (72%), but 28% had used e-cigarettes with nicotine. Male, White/Caucasian, and rural students, as well as those with a history of using tobacco cigarettes, were at greater odds of e-cigarette use. Seven percent of students who had never smoked a tobacco cigarette in their lifetime reported using an e-cigarette. Five percent of those who had ever used an e-cigarette had never smoked a tobacco cigarette.
  
  
  CONCLUSIONS
  More students reported ever using e-cigarettes without nicotine than with nicotine in Ontario, Canada. This underscores the need for greater knowledge of the contents of both nicotine and nonnicotine e-cigarettes to better guide public health policies.
authors.affiliation: Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada; hayley.hamilton@camh.ca.
authors.forename: Hayley A
authors.initials: HA
authors.lastname: Hamilton
authors.affiliation: Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada; Ontario Tobacco Research Unit, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Roberta
authors.initials: R
authors.lastname: Ferrence
authors.affiliation: Centre for Addiction and Mental Health, Toronto, Ontario, Canada;
authors.forename: Angela
authors.initials: A
authors.lastname: Boak
authors.affiliation: Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada; Ontario Tobacco Research Unit, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Robert
authors.initials: R
authors.lastname: Schwartz
authors.affiliation: Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada;
authors.forename: Robert E
authors.initials: RE
authors.lastname: Mann
authors.affiliation: Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada; Ontario Tobacco Research Unit, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Shawn
authors.initials: S
authors.lastname: O'Connor
authors.affiliation: Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada;
authors.forename: Edward M
authors.initials: EM
authors.lastname: Adlaf
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior; D066300:Electronic Nicotine Delivery Systems / Q000706:statistics & numerical data*; D005260:Female; D006306:Health Surveys; D006801:Humans; D008297:Male; D009538:Nicotine / Q000008:administration & dosage*; D009864:Ontario / Q000453:epidemiology; D012574:Schools; D012907:Smoking / Q000453:epidemiology; D000074606:Smoking Prevention; D013334:Students / Q000523:psychology / Q000706:statistics & numerical data*
chemical_list: D009538:Nicotine