Funding for this research was provided by:
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (PZ00P3_154709/1)
Received: 30 May 2018
Accepted: 28 February 2019
First Online: 7 March 2019
Ethics approval and consent to participate
: The study has been approved by the local ethical review board (EKNZ, approval number 2016–01183). This was a retrospective study so the consent to participate was waivered by the local ethical review board. General consent was signed by a majority.
: Not applicable.
: The authors declare that they have no competing interests.
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