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Article History

Received: 22 January 2018

Accepted: 1 October 2018

First Online: 20 October 2018

Ethics approval and consent to participate

: The study was approved by the Southeastern Norway Regional Committee for Medical and Health Research, approval number 2013/396b. All participants consented to participate based on written and oral information approved by the Committee. All patients received comprehensive written and oral information and signed an informed consent prior to participation.

: Not applicable

: The authors declare that they have no competing interests.

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