Aims

To compare Brief Advice (BA), Motivational Interviewing (MI), Rate Reduction (RR), and combined Motivational Interviewing and Rate Reduction (MI+RR) to promote smoking cessation in smokers not ready to quit.

Design

Randomized controlled trial with 4 parallel groups of smoking cessation intervention. Participants were randomly assigned 1:2:2:2 to receive one of the following interventions: BA (n=128), MI (n=258), RR (n=257), and MI+RR (n=260).

Setting

USA. All participant contact occurred over the telephone to be consistent with the typical quit line format.

Participants

903 adult smokers. Participants had a mean age of 49 (SD=13.3) years, and were 28.9% male and 63.3% Caucasian.

Interventions

The BA group received advice similar to typical smoking cessation quit lines. The MI group received advice using basic MI principles to elicit language that indicates behavioral change. The RR group received behavioral skills training and nicotine gum. The MI+RR group combined elements of MI and RR conditions. All interventions were six session.

Measurements

The primary outcome measure was self-reported point prevalence at 12 months. The secondary outcome was self-reported prolonged abstinence at 12 months.

Findings

Intention to treat (ITT) point prevalence at 12 months indicated that BA (10.9%) had significantly lower point prevalence rates than RR (27.2%, odds ratio (OR)=3.17, 1.69 to 5.94), and MI+RR (26.9%, OR=3.16, 1.68 to 5.93). BA did not have a significantly lower point prevalence rate than MI (15.5%, OR=1.56, 95% confidence interval (CI) = 0.81 to 3.02).

Conclusions

This randomized controlled trial provided evidence that rate reduction, which offers structured behavioral skills and nicotine gum, either alone or combined with motivational interviewing, is the most effective form of cessation intervention for smokers not ready to quit.