Text and Data Mining valid from 2018-05-02
Received: 3 August 2017
Accepted: 24 April 2018
First Online: 2 May 2018
Ethics approval and consent to participate
: The study had been approved by the local ethical committee of the Medical faculty, University of Tuebingen (project number 076/2012BO1). Informed written consent was obtained from each patient included into the study, and the study protocol conforms to the ethical guidelines of the 1975 Declaration of Helsinki.
: The authors declare that they have no competing interests.
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