Funding for this research was provided by:
State of Saxony-Anhalt and European Union, European Regional Development Fund
Received: 18 December 2017
Accepted: 11 May 2018
First Online: 21 May 2018
Ethics approval and consent to participate
: The ethics committee of the Faculty of Medicine of the Otto-von-Guericke-University Magdeburg has reviewed and approved all data management and outcome-related activities of this research project (Reference number: 25/16). Patients provided their written consent to participate in the study prior to any examination.
: The authors declare that they have no competing interests.
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