Cluster randomised controlled trial of expert system based on the transtheoretical (“stages of change”) model for smoking prevention and cessation in schools

• Published in: BMJ 1999-10, Vol.319 (7215), p.948-953
• Main Authors: Aveyard, Paul, Cheng, K K, Almond, Joanne, Sherratt, Emma, Lancashire, Robert, Lawrence, Terry, Griffin, Carl, Evans, Olga
• Format: Article
• Language: English
• Subjects: Addictive behavior; Adolescent; Adolescents; Behavior modeling; Behavior Therapy - methods; Cigarette smoking; Computers; Control groups; Education; England - epidemiology; Expert systems; Feasibility studies; Female; Humans; Intervention; Lost to follow up; Male; Outcome Assessment (Health Care); Personal health; Prevalence; Psychoeducational intervention; Questionnaires; School Health Services - organization & administration; Schools; Smoking; Smoking Cessation; Smoking Prevention; Students; Teacher supervision; Teenagers
• ISSN: 0959-8138; 1468-5833; 1756-1833
• DOI: 10.1136/bmj.319.7215.948

Abstract Objectives: To examine whether a year long programme based on the transtheoretical model of behaviour change, incorporating three sessions using an expert system computer program and three class lessons, could reduce the prevalence of teenage smoking. Design: Cluster randomised trial comparing the intervention to a control group exposed only to health education as part of the English national curriculum. Setting: 52 schools in the West Midlands region. Participants: 8352 students in year 9 (age 13-14 years) at those schools. Main outcome measures: Prevalence of teenage smoking 12 months after the start of the intervention. Results: Of the 8352 students recruited, 7444 (89.1%) were followed up at 12 months. The intention to treat odds ratio for smoking in the intervention group relative to control was 1.08 (95% confidence interval 0.89 to 1.33). Sensitivity analysis for loss to follow up and adjustment for potential confounders did not alter these findings. Conclusions: The smoking prevention and cessation intervention based on the transtheoretical model, as delivered in this trial, is ineffective in schoolchildren aged 13-14. Key messages The transtheoretical model proposes that individuals move through a series of stages in behaviour change A computer programme gave 13 and 14 year old school students tailored information about what stage they were in and what to do to move to the next stage Students given this information were no more likely to move stage, refrain from smoking, or stop smoking than those exposed to ordinary classroom health education There is no evidence that the computerised expert system based on the transtheoretical model is effective in smoking prevention and cessation