title: Group hypnosis vs. relaxation for smoking cessation in adults: a cluster-randomised controlled trial.
abstract: BACKGROUND
  Despite the popularity of hypnotherapy for smoking cessation, the efficacy of this method is unclear. We aimed to investigate the efficacy of a single-session of group hypnotherapy for smoking cessation compared to relaxation in Swiss adult smokers.
  
  
  METHODS
  This was a cluster-randomised, parallel-group, controlled trial. A single session of hypnosis or relaxation for smoking cessation was delivered to groups of smokers (median size = 11). Participants were 223 smokers consuming ≥ 5 cigarettes per day, willing to quit and not using cessation aids (47.1% females, M = 37.5 years [SD = 11.8], 86.1% Swiss). Nicotine withdrawal, smoking abstinence self-efficacy, and adverse reactions were assessed at a 2-week follow-up. The main outcome, self-reported 30-day point prevalence of smoking abstinence, was assessed at a 6-month follow up. Abstinence was validated through salivary analysis. Secondary outcomes included number of cigarettes smoked per day, smoking abstinence self-efficacy, and nicotine withdrawal.
  
  
  RESULTS
  At the 6-month follow up, 14.7% in the hypnosis group and 17.8% in the relaxation group were abstinent. The intervention had no effect on smoking status (p = .73) or on the number of cigarettes smoked per day (p = .56). Smoking abstinence self-efficacy did not differ between the interventions (p = .14) at the 2-week follow-up, but non-smokers in the hypnosis group experienced reduced withdrawal (p = .02). Both interventions produced few adverse reactions (p = .81).
  
  
  CONCLUSIONS
  A single session of group hypnotherapy does not appear to be more effective for smoking cessation than a group relaxation session.
  
  
  BACKGROUND
  Current Controlled Trials ISRCTN72839675.
authors.affiliation: Swiss Research Institute for Public Health and Addiction ISGF, University of Zurich, Konradstrasse 32, Postfach, 8031 Zürich, Switzerland. maria.dickson@isgf.uzh.ch.
authors.forename: Maria
authors.initials: M
authors.lastname: Dickson-Spillmann
authors.forename: Severin
authors.initials: S
authors.lastname: Haug
authors.forename: Michael P
authors.initials: MP
authors.lastname: Schaub
mesh_terms: D000328:Adult; D016000:Cluster Analysis; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006990:Hypnosis; D008297:Male; D008875:Middle Aged; D011615:Psychotherapy, Group / Q000379:methods*; D012064:Relaxation Therapy; D016540:Smoking Cessation / Q000379:methods* / Q000706:statistics & numerical data; D000074606:Smoking Prevention; D013557:Switzerland; D016896:Treatment Outcome