Funding for this research was provided by:
Received: 29 June 2020
Accepted: 25 August 2020
First Online: 13 October 2020
Ethics approval and consent to participate
: The study was approved by the regional ethics committee (2012/542/REK vest). Written informed consents were obtained from the parents/legal representatives and the adolescents. The study was registered at ClinicalTrials.gov (No: NCT03904459).
: Not applicable.
: The authors declare that they have no competing interests.