Background: Smoking and poor mental health in youth represent important public health priorities. This study aimed to (i) compare tobacco-related behaviors and mental health in two educational settings with high smoking rates: vocational education and training (VET) schools and preparatory basic education (PBE) schools, and (ii) examine associations between smoking at school start and mental health 5 months later.
Methods: Data were obtained from baseline ( = 1843) and follow-up ( = 1039) assessments conducted as part of a school-based trial in two rounds (baseline in August 2018 and August 2019).