title: Effectiveness of a web-based self-help smoking cessation intervention: protocol of a randomised controlled trial.
abstract: BACKGROUND
  Cigarette smoking is a major risk factor for many chronic and fatal illnesses. Stopping smoking directly reduces those risks. The aim of this study is to investigate the effectiveness of a web-based interactive self-help programme for smoking cessation, known as the StopSite, by comparing it to an online self-help guide. Both interventions were based on cognitive-behavioural and self-control principles, but the former provided exercises, feedback and interactive features such as one-to-one chatrooms and a user forum, which facilitated mutual support and experience sharing.
  
  
  METHODS
  We conducted a randomised controlled trial to compare the interactive intervention with the self-help guide. The primary outcome measure was prolonged abstinence from smoking. Secondary outcomes were point-prevalence abstinence, number of cigarettes smoked, and incidence of quit attempts reported at follow-up assessments. Follow-up assessments took place three and six months after a one-month grace period for starting the intervention after baseline. Analyses were based on intention-to-treat principles using a conservative imputation method for missing data, whereby non-responders were classified as smokers.
  
  
  CONCLUSIONS
  The trial should add to the body of knowledge on the effectiveness of web-based self-help smoking cessation interventions. Effective web-based programmes can potentially help large numbers of smokers to quit, thus having a major public health impact.
  
  
  BACKGROUND
  ISRCTN74423766.
authors.affiliation: Innovation Centre of Mental Health and Technology, Trimbos Institute, AS Utrecht, the Netherlands. jkramer@trimbos.nl
authors.forename: Jeannet Jam
authors.initials: JJ
authors.lastname: Kramer
authors.forename: Marc C
authors.initials: MC
authors.lastname: Willemsen
authors.forename: Barbara
authors.initials: B
authors.lastname: Conijn
authors.forename: Andrée J
authors.initials: AJ
authors.lastname: van Emst
authors.forename: Suzanne
authors.initials: S
authors.lastname: Brunsting
authors.forename: Heleen
authors.initials: H
authors.lastname: Riper
mesh_terms: D000293:Adolescent; D000328:Adult; D001521:Behavior Therapy / Q000379:methods*; D016009:Chi-Square Distribution; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D020407:Internet / Q000706:statistics & numerical data*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D010349:Patient Compliance; D011336:Probability; D012657:Self-Help Groups / Q000706:statistics & numerical data*; D012680:Sensitivity and Specificity; D016540:Smoking Cessation / Q000379:methods* / Q000523:psychology; D013813:Therapy, Computer-Assisted; D016896:Treatment Outcome; D055815:Young Adult