Correction

Nicotine nasal spray with nicotine patch for smoking cessation: randomised trial with six year follow up

Two errors occurred in this paper by Thorsteinn Blondal and colleagues (30 January, pp 285-9). The results section of the abstract should read "Sustained abstinence rates for the patch and nasal spray group and patch only group were 51% v 35% after 6 weeks (odds ratio 1.97, 95% confidence interval 1.17 to 3.32; P=0.011(²)), 37% v 25% after 3 months (1.76, 1.01 to 3.08; P=0.045), 31% v 16% after 6 months (2.40, 1.27 to 4.50; P=0.005), 27% v 11% after 12 months (3.03, 1.50 to 6.14; P=0.001), and 16% v 9% after 6 years (2.09, 0.93 to 4.72; P=0.08)."

The statistical analyses section should read "We based the number of participants required for the efficacy analysis on a significance level of 5% using a one tailed test, a power of 90%, and there being 55% of participants in the patch and nasal spray group and 35% in the patch and placebo group, successful after 3 months; 105 participants were needed in each treatment group."