Funding for this research was provided by:
Stiftung Rheinland-Pfalz für Innovation (AZ 961-386261/733)
Johannes Gutenberg-University of Mainz
Boehringer Ingelheim (n/a)
PHILIPS Medical Systems (n/a)
Received: 14 December 2018
Accepted: 13 May 2019
First Online: 6 June 2019
Ethics approval and consent to participate
: The study protocol and study documents were approved by the local ethics committee of the Medical Chamber of Rhineland-Palatinate, Germany (reference no. 837.020.07; original vote: 22.3.2007, latest update: 20.10.2015). According to the tenets of the Declaration of Helsinki, written informed consent was obtained from all participants prior to entering the study.
: Not applicable.
: The authors declare that they have no competing interests.
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