A Cochrane review included 53 studies with a total of 25 000 subjects. Most studies provided nicotine replacement therapy (NRT). Behavioural support was typically provided by specialists in cessation counselling includin 4 to 8 sessions. One large study (the Lung Health Study) yielded a substantially larger treatment effect than seen in other studies (RR 3.88, 95% CI 3.35 to 4.50). Since this study used a particularly intensive intervention which included extended availability of nicotine gum, multiple group sessions and long term maintenance and recycling contacts, the results may not be comparable with the interventions used in other studies, and hence it was not pooled in other analyses. The remaining 52 studies showed benefit of combined pharmacotherapy and behavioural treatment compared to usual care, brief advice or less intensive behavioural support (RR 1.83, 95% CI 1.68 to 1.98; n=19488; I² = 36 %; high quality evidence). The pooled estimate for 43 trials that recruited participants in healthcare settings (RR 1.97, 95% CI 1.79 to 2.18) was higher than for 8 trials with community-based recruitment (RR 1.53, 95% CI 1.33 to 1.76).
Date of latest search: 24 July 2015