Funding for this research was provided by:
Deutsche Forschungsgemeinschaft (SCHW 899/4-2)
Received: 11 July 2018
Accepted: 17 August 2018
First Online: 28 September 2018
Ethics approval and consent to participate
: The study protocol was approved by the ethics committee (4837R) of the Heinrich Heine University, Düsseldorf, Germany, and registered via the Internet Portal of the German Clinical Trials Register (DRKS00009586). Each patient was given a detailed description of the study procedures and signed a consent to participate.
: Consent for publication was obtained from all participants.
: Puria Parvini, Robert Sader, Didem Sahin, Jürgen Becker, and Frank Schwarz declare that they have no competing interests.
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