Counselor and stimulus control enhancements of a stage-matched expert system intervention for smokers in a managed care setting.

ABSTRACT

BACKGROUND: Previous research has demonstrated the efficacy of an interactive expert system intervention for smoking cessation for a general population. The intervention provides individualized feedback that guides participants through the stages of change for cessation. Enhancing the expert system by adding proactive telephone counseling or a stimulus control computer designed to produce nicotine fading could produce preventive programs with greater population impacts. METHODS: Four interventions were compared (a) the interactive expert system intervention; (b) the expert system intervention plus counselor calls; (c) the expert system intervention plus the stimulus control computer; and (d) an assessment only condition. A 4 (intervention) x 4 (occasions) (0,6,12, and 18 months) design was used. Smokers were contacted at home via telephone or mail. The initial subject pool was the 24,178 members of a managed care company. Screening was completed for 19,236 members (79.6%), of whom 4,653 were smokers; 85.3% of the smokers were enrolled. RESULTS: Thirty-eight percent were in the precontemplation stage, 45% in the contemplation stage, and only 17% in the preparation stage. At 18 months, the expert system resulted in 23.2% point prevalence abstinence, which was 33% greater than that of assessment only. The counselor enhancement produced increased cessation at 12 months but not at 18 months. The stimulus control computer produced no improvement, resulting in 20% worse cessation rates than the assessment only condition. CONCLUSIONS: The enhanced conditions failed to outperform the expert system alone. The study also demonstrated the ability of the interactive expert system to produce significantly greater cessation in a population of smokers than assessment alone.