Effects of interventions to combat tobacco addiction: Cochrane update of 2019 and 2020 reviews.

There is high certainty that using nicotine replacement therapy from quit day increases smoking abstinence and no further research is required. Evidence is less certain that nicotine replacement increases abstinence when used in higher doses tailored to particular groups of smokers or use prior to quit day and further research would be helpful. There is moderate certainty evidence to support the use of e-cigarettes as cessation aids, but research on their role in preventing relapse would be particularly helpful.