Text and Data Mining valid from 2019-04-15
Received: 22 October 2018
Accepted: 3 April 2019
First Online: 15 April 2019
Ethics approval and consent to participate
: The protocol of the present study was approved by the local ethics committee (Kantonale Ethik-Kommission Zürich, KEK-ZH-Nr. 2014–0557, and Amendment of November 24, 2015).The need for individual informed consent was waived by the ethics committee but it was assured that patients included into this analysis had not objected to use of their data for research purposes.
: Not applicable.
: CMLW is a member of the editorial board (Associate Editor) of BMC Surgery. All other authors declare that they have no conflicts of interests.
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