Funding for this research was provided by:
Bundesministerium für Bildung und Forschung (FKZ 01EO1502)
Received: 3 November 2017
Accepted: 29 December 2017
First Online: 18 January 2018
Ethics approval and consent to participate
: The study was approved by the internal review board of the Jena University Hospital. Since a secondary analysis of claims data is done, the need for informed consent of patients was waved. The study was additionally approved by the data protection supervisor of the Free State of Thuringia, Germany.
: Not applicable.
: The authors declare that they have no competing interests.
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