Received: 14 May 2018
Accepted: 24 September 2018
First Online: 26 October 2018
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of the Medical University of Vienna (Borschkegasse 8b/E06, 1090 Vienna, Austria; chairperson: Martin Brunner; protocol number: 2194/2017) and is in accordance with the Helsinki Declaration of 1975 as well as the institution’s standards of good scientific practice. All obtained subject data were pseudonymized in an investigator file and handled under the strictest confidence. For this type of study, formal consent was not required.
: Not applicable.
: The authors declare that they have no competing interests.
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