Funding for this research was provided by:
Horizon 2020 (754849)
Kavli Trust (A-321629)
Received: 25 August 2020
Accepted: 2 March 2021
First Online: 16 March 2021
: The recruitment analysis reported in the present study does not require ethical review according to Swedish legislation (SFS 2003:460). Both trials were approved by the Regional Ethics Review Board in Uppsala (Ref. no: 2018/382; 2019–031160), Etikprövningsmyndigheten (Swedish Ethical Review Authority). Once a school agreed to participate, eligible youth and legal guardians (for youth < 15 years old) were provided with information sheets approved by the Ethics Review Board as part of the informed consent process. Consent to participate was written and provided by the legal guardians for youth < 15 years old.
: Not applicable.
: The authors do not have any competing interests to declare.