A Cochrane review [Abstract] 1 included 104 studies with a total of 111 653 participants. Among smokers who contacted helplines, quit rates were higher for groups randomised to receive multiple sessions of proactive counselling (RR 1.38, 95% CI 1.19 to 1.61; 14 trials, n=32 484; I²=72%). Telephone counselling not initiated by calls to helplines also increased quitting (RR 1.25, 95% CI 1.15 to 1.35; 65 trials, n=41 233; I²=52%). In a meta-regression controlling for other factors the effect was estimated to be slightly larger if more calls were offered. The relative extra benefit of counselling was smaller when it was provided in addition to pharmacotherapy than when the control group only received self-help material or a brief intervention.
Comment: The quality of evidence is downgraded by unexplained heterogeneity.
Primary/Secondary Keywords