Funding for this research was provided by:
Ministero delle Politiche Agricole Alimentari e Forestali
National Prevention Research Initiative (G0701877)
The Research Council of Norway, Division for Society and Health.
Medical Research Council (MC_UU_12015/3; MC_UU_12015/7)
The Research Council of Norway (249932/F20)
Received: 2 September 2019
Accepted: 12 February 2020
First Online: 18 March 2020
Ethics approval and consent to participate
: Local ethics committee approval, parental/legal guardian consent, and child assent were obtained in all studies. Consent to participate outlined in the main methods section.
: Not applicable.
: The authors declare that they have no competing interests.