Received: 21 November 2018
Accepted: 30 January 2019
First Online: 13 February 2019
Ethics approval and consent to participate
: The Privacy Protection Supervisor at Haukeland University Hospital approved the study as a quality assurance study in the health service (Ref PVO 2014/2770) for the requirements of informed consent and ethical review were waived.
: Not applicable.
: The authors declare that they have no competing interests.
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