Objective A systematic review and meta-analysis to investigate the efficacy of interventions incorporating motivational interviewing for smoking cessation and identify correlates of treatment effects

Data sources Medline/PubMed, PsycInfo and other sources including grey literature

Study selection Title/abstract search terms were motivational interview* OR motivational enhancement AND smok*, cigarette*, tobacco, OR nicotine. Randomised trials reporting number of smokers abstinent at follow up were eligible.

Data extraction Data were independently coded by the first and third authors. We coded for a variety of study, participant, and intervention related variables.

Data synthesis A random effects logistic regression with both a random intercept and a random slope for the treatment effect.

Results 31 smoking cessation research trials were selected for the study: eight comprised adolescent samples, eight comprised adults with chronic physical or mental illness, five comprised pregnant/postpartum women and 10 comprised other adult samples. Analysis of the trials (9485 individual participants) showed an overall OR comparing likelihood of abstinence in the motivational interviewing (MI) versus control condition of OR 1.45 (95% CI 1.14 to 1.83). Additional potential correlates of treatment effects such as study, sample, and intervention characteristics were examined.

Conclusions This is the most comprehensive review of MI for smoking cessation conducted to date. These findings suggest that current MI smoking cessation approaches can be effective for adolescents and adults. However, comparative efficacy trials could be useful.