Sample size
With a final sample of 614 participants, we can detect a ≥ 5% difference between the IG and the CG regarding prolonged abstinence (absolute risk), assuming an abstinence rate of 2.5% in the CG, a power of 80% (beta risk), a significance level (alpha risk) of 5% in a two-tailed contrast, and a lost to follow-up of <5% of patients [