Received: 28 December 2018
Accepted: 14 May 2019
First Online: 22 May 2019
: Displayed on title page
: We had an ethics approval of the local internal review board, reference number 2017–209-f-S (Ethikkommission der Ärztekammer Westfalen-Lippe und der Westfälischen-Wilhelms Universität Münster). Consent was not deemed necessary by the ethics committee because this study is a retrospective analysis of routine clinical data.
: Consent was not deemed necessary by the ethics committee because this study is a retrospective analysis of routine clinical data. Consent for publication was not necessary because the manuscript does not contain individual data.
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