Funding for this research was provided by:
Strategiske Forskningsråd (2101-07-0023)
Text and Data Mining valid from 2018-12-01
Received: 14 March 2018
Accepted: 4 December 2018
First Online: 22 December 2018
Ethics approval and consent to participate
: The study was conducted in accordance with the Declaration of Helsinki and was approved by The National Committee on Health Research Ethics, protocol number (H-A-2008-111). Written informed consent was obtained from the parents or legal guardians of the participating children before enrolment. Only the children of parents capable of understanding oral and written Danish were included in the study. The study was approved by the Danish Data Protection Agency (protocol number 2013-41-2338).
: Written consent for publication has been obtained from the parents or legal guardians of all participants.
: The authors declare that they have no competing interests.
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