Text and Data Mining valid from 2018-03-27
Received: 19 June 2017
Accepted: 20 March 2018
First Online: 27 March 2018
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: All research has been conducted in accordance with the Declaration of Helsinki and need for approval has been waived by the ethics committee of the Medical Faculty of Heidelberg University. The need for consent to participate was waived by the ethics committee of the Medical Faculty of Heidelberg University.
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