Document is current

Article History

Received: 7 April 2017

Accepted: 23 August 2018

First Online: 4 September 2018

Ethics approval and consent to participate

: All procedures performed in this study were reviewed and approved by Regional Committee for Medical and Health Research Ethics- Region West in Norway (2009/2591) and were done in accordance with the 1964 Helsinki declaration.

: Not Applicable.

: The authors declare that they have no competing interest.

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