title: Predictors of Utilization of a Novel Smoking Cessation Smartphone App.
abstract: BACKGROUND
  Understanding the characteristics of high and low utilizers of smartphone applications (apps) for smoking cessation would inform development of more engaging and effective apps, yet no studies to date have addressed this critical question. Informed by prior research on predictors of cessation Web site utilization, this study examines the degree to which baseline demographic factors (gender, age, and education), smoking-related factors (smoking level and friends' smoking), and psychological factors (depression and anxiety) are predictive of utilization of a smartphone app for smoking cessation called SmartQuit.
  
  
  METHODS
  Data came from 98 participants randomized to SmartQuit as part of a pilot trial from March to May 2013. We used negative binomial count regressions to examine the relationship between user characteristics and utilization of the app over an 8-week treatment period.
  
  
  RESULTS
  Lower education (risk ratio [RR]=0.492; p=0.021), heavier smoking (RR=0.613; p=0.033), and depression (RR=0.958; p=0.017) prospectively predicted lower app utilization. Women (RR=0.320; p=0.022), those with lower education (RR=0.491; p=0.013), and heavier smokers (RR=0.418; p=0.039) had lower utilization of app features known to predict smoking cessation.
  
  
  CONCLUSIONS
  Many of the predictors of utilization of smoking cessation apps are the same as those of cessation Web sites. App-delivered smoking cessation treatment effectiveness could be enhanced by focusing on increasing engagement of women, those with lower education, heavy smokers, and those with current depressive symptoms.
authors.affiliation: 1 Department of Psychology, University of Washington , Seattle, Washington.|2 Division of Public Health Sciences, Fred Hutchinson Cancer Research Center , Seattle, Washington.
authors.forename: Emily Y
authors.initials: EY
authors.lastname: Zeng
authors.affiliation: 2 Division of Public Health Sciences, Fred Hutchinson Cancer Research Center , Seattle, Washington.|3 Department of Psychiatry and Behavioral Sciences, University of Washington , Seattle, Washington.
authors.forename: Roger
authors.initials: R
authors.lastname: Vilardaga
authors.affiliation: 2 Division of Public Health Sciences, Fred Hutchinson Cancer Research Center , Seattle, Washington.
authors.forename: Jaimee L
authors.initials: JL
authors.lastname: Heffner
authors.affiliation: 2 Division of Public Health Sciences, Fred Hutchinson Cancer Research Center , Seattle, Washington.
authors.forename: Kristin E
authors.initials: KE
authors.lastname: Mull
authors.affiliation: 1 Department of Psychology, University of Washington , Seattle, Washington.|2 Division of Public Health Sciences, Fred Hutchinson Cancer Research Center , Seattle, Washington.
authors.forename: Jonathan B
authors.initials: JB
authors.lastname: Bricker
mesh_terms: D005260:Female; D006801:Humans; D008297:Male; D063731:Mobile Applications / Q000706:statistics & numerical data*; D000068997:Smartphone; D016540:Smoking Cessation; D055815:Young Adult
keywords: applications; mobile health; nicotine; smartphone; smoking cessation; tobacco; utilization