Funding for this research was provided by:
Deutsche Forschungsgemeinschaft (RA 799/5-1)
Text and Data Mining valid from 2020-02-17
Received: 6 November 2019
Accepted: 26 January 2020
First Online: 17 February 2020
Ethics approval and consent to participate
: The study protocol was approved by the local Ethics Committee and was performed in accordance to the ethics principles in the Declaration of Helsinki. All participants signed a written informed consent.
: Not applicable.
: The authors declare that they have no competing interests.