Editor—My colleagues and I have read the article by Aveyard et al on smoking prevention and cessation in schools, which examines the use of computer delivered expert system interventions that we have developed.1
For unreported reasons, Aveyard et al applied our adult dose for smoking to an adolescent population. In our standard adult protocol we provide three expert system interventions over six to 12 months. Aveyard et al provided three expert system interventions to adolescents over a comparable period of time. Our behaviour change protocol for adolescent populations calls for six to eight expert system interventions over two academic years. One of the reasons our treatment with adolescents is at least twice as long, with more expert system interventions, is that smoking increases over a two year period with adolescents, whereas it decreases with adults. Why would Aveyard et al expect an adult dose for smoking to be effective with adolescents? I know of no evidence, and Aveyard et al provide no evidence or rationale, for applying our adult dose of expert systems to adolescents.
We will soon be reporting on the important pattern of results that were produced when our two year adolescent protocol was applied to an adolescent population.
Footnotes
Competing interests: I am one of the developers of the expert system under discussion. The expert systems for smoking are owned by the University of Rhode Island and are licensed to Johnson and Johnson Health Services. A sublicence has been developed with Nelson Communications in the United States and Public Management Associates for commercial use in the United Kingdom. Pro-Change Behavior Systems, LLC, of which I am a principal, provides research and development services to these two companies.
References
- 1.Aveyard P, Cheng KK, Almond J, Sherratt E, Lancashire R, Lawrence T, et al. Cluster randomised controlled trial of expert system based on the transtheoretical (“stages of change”) model for smoking prevention and cessation in schools. BMJ. 1999;319:948–953. doi: 10.1136/bmj.319.7215.948. . (9 October.) [DOI] [PMC free article] [PubMed] [Google Scholar]