Received: 23 August 2017
Accepted: 8 January 2019
First Online: 30 January 2019
Ethics approval and consent to participate
: All studies on humans described in the present manuscript were carried out in accordance with national law and the Helsinki Declaration of 1975 (in its current, revised form). The pretest studies were approved by the responsible ethics committee of the German Federal States of each of the 18 study centers (such as for Augsburg: Ethics Committee of the State Board of Physicians of the German federal state of Bavaria; Bremen: Ethics Committee of the University of Bremen; Essen: Ethics Committee of the University Clinics of Essen; Hannover: Ethics Committee of the State Board of Physicians of the German federal state of Lower Saxony; Hamburg: Ethics Committee of the State Board of Physicians of the federal state of Hamburg; and Heidelberg: Ethics Committee of the Medical Faculty of Heidelberg). Written informed consent was obtained from all participants included in the studies.
: Not applicable.
: The authors declare that they have no competing interests.
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