Funding for this research was provided by:
Svenska Forskningsrådet Formas (2016-00353)
Received: 10 January 2020
Accepted: 17 June 2020
First Online: 24 June 2020
Ethics approval and consent to participate
: This study was conducted in line with the Declaration of Helsinki [CitationRef removed]. Information about the study was provided to pupils and parents before data collection by the schools through their internal weekly newsletter. Ethical approval was obtained from the Swedish Ethical Review Authority (No. 2019–01281).
: Not applicable.
: The authors declare that they have no competing interests.