Text and Data Mining valid from 2019-01-22
Received: 10 October 2018
Accepted: 2 January 2019
First Online: 22 January 2019
Ethics approval and consent to participate
: The study protocol was approved by the local ethics committee (195/2014BO2). Written consent of the ethics committee of the medical university of Tübingen is available.
: “Not applicable”.
: The authors declare that they have no competing interests.
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