Text and Data Mining valid from 2018-03-16
First Online: 16 March 2018
Compliance with Ethical Standards
: Gerd Willmund and Peter Zimmermann are employed by the German Armed Forces. Their employment had no influence on the study design. All authors declare that they have no conflict of interest.
: The protocol was approved by the ethics committee of Charité University Clinic, Berlin, Germany.
: All procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (national and institutional). Informed consent was obtained from all individual subjects participating in the study. All subjects gave written informed consent in accordance with the Declaration of Helsinki.
: No animal studies were carried out by the authors for this article.