Article History
Received: 22 August 2017
Accepted: 26 December 2018
First Online: 9 January 2019
Ethics approval and consent to participate
: The Ethics Committee of the Canton Bern (KEK) approved the study (KEK-Nr. Req-2017_00257). Informed consent was not necessary, as the analyses were done with routine clinical data for quality assurance purposes.
: Not applicable.
: The authors declare that they have no competing interests.
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