Text and Data Mining valid from 2018-05-15
Received: 5 March 2018
Accepted: 19 April 2018
First Online: 15 May 2018
Ethics approval and consent to participate
: Retrospective evaluation of the data was in accordance with the ethical standards of the institutional research committee of each site and approved accordingly (sites 1 and 2: ethics committee of the University Hospital Carl Gustav Carus of the Technische Universität Dresden – EK248072013; site 3: ethics committee of the University Hospital Magdeburg A.ö.R. – 100/14). Written informed consent was obtained from all individual participants included in the study. Patients were diagnosed and treated according to national guidelines and the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.
: The authors declare that they have no competing interests.
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