Article History
Received: 16 November 2017
Accepted: 19 November 2018
First Online: 7 January 2019
Ethics approval and consent to participate
: The 1964 Declaration of Helsinki and its later amendments guided the study’s ethics considerations and choices. The Regional Committee for Medical and Health Research Ethics (REK) in South- eastern Norway approved the study with reference number 2013/1335. So did Norwegian Social Science Data Service (NSD), with reference number 35573. The Department for Child and Adolescent Mental Health and the Research Unit at the hospital gave their permission.Informed written consent was obtained from all individual participants included in the study.
: Not applicable.
: The authors declare that they have no competing interests.
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