Received: 12 March 2021
Accepted: 12 October 2021
First Online: 8 November 2021
: The study was conducted in accordance with the Helsinki Declaration. Both parents and children received written information about the study. The parents gave written consent on behalf of their children. The Regional Committee for Medical and Health Research Ethics in Central Norway approved the follow-up study (REC no. 2014/618, July 7th 2014).
: Not applicable.
: The authors declare that they have no competing interests.