Article History
Received: 13 March 2018
Accepted: 29 October 2018
First Online: 14 November 2018
Ethics approval and consent to participate
: According to Danish law, only studies gathering human tissue need approval from an ethics committee. Permission to conduct the study was granted by the Danish Data Protection Agency. All participants received written information about the study prior to giving consent. Informed and written consent was obtained from all participants upon the agreement that their identities would be revealed, and that they could withdraw from participation at any time.
: Not applicable.
: The authors declare that they have no competing interests.
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