The study, called ESTxENDS (Efficacy, Safety, Toxicology of Electronic Nicotine Delivery Systems), involved more than 1,200 participants in five Swiss cities (Berne, Geneva, Lausanne, St. Gallen and Zurich). The participants, aged 38 on average, had been regular smokers since their teens.
They were randomly divided into two groups : those receiving an electronic cigarette and those receiving standard advice on how to quit smoking.