Funding for this research was provided by:
German Federal Ministry of Education and Research (01EA1408A-G)
Text and Data Mining valid from 2018-06-27
Received: 11 August 2017
Accepted: 22 May 2018
First Online: 27 June 2018
Ethics approval and consent to participate
: The study was approved by the Ethical Committee of the Federal State of Brandenburg and written informed consent was obtained from all participants at time of recruitment.
: Not applicable.
: The authors declare that they have no competing interests.
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