RESEARCH REPORT © 2003 Society for the Study of Addiction to Alcohol and Other Drugs Addiction, 98, 345–354 Blackwell Science, LtdOxford, UKADDAddiction0965-2140© 2003 Society for the Study of Addiction to Alcohol and Other Drugs 98Original ArticleTranstheoretical model trialPaul Aveyard et al. Correspondence to: Paul Aveyard Department of Public Health and Epidemiology University of Birmingham Birmingham B15 2TT UK Tel: + 44 121 414 4532 Fax: + 44 121 414 7692 E-mail: p.n.aveyard@bham.ac.uk Submitted 8 April 2002; initial review completed 25 July 2002; final version accepted 5 September 2002 A controlled trial of an expert system and self-help manual intervention based on the stages of change versus standard self-help materials in smoking cessation Paul Aveyard * , Carl Griffin * , Terry Lawrence & K. K. Cheng Department of Public Health and Epidemiology, University of Birmingham, Birmingham, UK ABSTRACT Aim To examine the population impact and effectiveness of the Pro-Change smoking cessation course based on the Transtheoretical Model (TTM) compared to standard self-help smoking cessation literature. Design Randomized controlled trial. Setting Sixty-five West Midlands general practices. Participants Randomly sampled patients recorded as smokers by their general practitioners received an invitation letter and 2471 current smokers agreed. Interventions Responders were randomized to one of four interventions. The control group received standard self-help literature. In the Manual intervention group, participants received the Pro-Change system, a self-help workbook and three questionnaires at 3-monthly intervals, which generated individually tai- lored feedback. In the Phone intervention group, participants received the Manual intervention plus three telephone calls. In the Nurse intervention group, participants received the Manual intervention plus three visits to the practice nurse. Measurements Biochemically confirmed point prevalence of being quit and 6- month sustained abstinence, 12 months after study commencement. Findings A total of 9.1% of registered current smokers participated, of whom 83.0% were not ready to quit. Less than half of participants returned question- naires to generate second and third individualized feedback. Telephone calls reached 75% of those scheduled, but few participants visited the nurse. There were small differences between the three Pro-Change arms. The odds ratio (95% confidence intervals) for all Pro-Change arms combined versus the control arm were 1.50 (0.85–2.67) and 1.53 (0.76–3.10), for point prevalence and 6- month abstinence, respectively. This constitutes 2.1% of the TTM group versus 1.4% of the control group achieving confirmed 6-month sustained abstinence. Conclusions There was no statistically significant benefit of the intervention apparent in this trial and the high relapse of quitters means that any population impact is small. KEYWORDS Smoking cessation, Transtheoretical Model. INTRODUCTION The British Government’s smoking cessation strategy is to train general practitioners (GPs) to increase the propor- tion of smokers that they advise to stop smoking and to encourage patients intending to act on this advice to attend smoking cessation clinics (Secretary of State for Health 1998). The guidelines for this strategy suggest that this could increase the number of smokers who attempt to stop each year in England from about 3.4 mil- *Joint first authors.