Received: 28 May 2019
Accepted: 10 July 2019
First Online: 19 July 2019
Ethics approval and consent to participate
: The study was approved by the Local Ethics Committee of the Medical University of Vienna (project number 368/2011).Informed consent was obtained from all included surviving patients. In deceased patients, informed consent was obtained either from the patient prior to death or the closest relative, or from the patient’s legal representative.No individual participant’s data were used in this study.
: Not applicable.
: The authors declare that they have no competing interests.