INTRODUCTION
European estimates of adolescent smoking cessation are lacking and studies on the role of schools in quit behaviour are scarce. We aimed to describe smoking cessation attempts and success among adolescents in Europe and explored the association with school policy and programmes.

METHODS
We used cross-sectional data from the 2013 and 2016-2017 surveys of the European SILNE and SILNE-R projects. We included 4,509 12-19-year-old current or ex-smokers in 67 secondary schools in seven countries (Belgium, Germany, Finland, Ireland, Italy, the Netherlands, and Portugal). School staff reported strength of smoke-free school policies (SFSPs), proportion of grades in which anti-tobacco education was offered, and whether the school offered any form of cessation support programme. Multilevel logistic regression analysis determined school-level variation and the association of school-level and individual-level variables with self-reported and self-defined quit attempts and quit success.

RESULTS
Over three quarters (77.3%) of students reported a quit attempt and half of them (50.1%) reported quit success. Prevalence rates of quit success and quit attempts, showed relatively small variations between schools within countries. Associations of smoke-free school policy, tobacco educational programmes and cessation programmes with quit attempts and quit success could not be demonstrated with statistical significance. Quit attempts and quit success were inversely associated with alcohol use, parental smoking, and friend smoking.

CONCLUSION
This study demonstrates that adolescence is an important time to encourage quitting and to support quit attempts. We did not find evidence for a contribution of school policies and programmes to quit behaviour of adolescent smokers.