Funding for this research was provided by:
Norwegian Directorate of Health
Received: 26 May 2018
Accepted: 17 January 2019
First Online: 30 January 2019
Ethics approval and consent to participate
: The trial was approved by The Regional Committee for Medical and Health Research Ethics for Western Norway (REK West, 2014/57–1). Each participant signed a declaration of voluntary participation with information about the study purposes and consequences, emphasizing the right to withdraw from the study.
: Not applicable.
: The authors declare that they have no competing interests.
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