Text and Data Mining valid from 2019-09-05
Received: 9 June 2019
Accepted: 20 August 2019
First Online: 5 September 2019
Ethics approval and consent to participate
: The local ethics committee, Charité—Universitätsmedizin Ethikkommission Berlin, Germany, approved the study (Charité-EA2/187/18).
: Obtaining consent of publication was not necessary as not individual person’s data are presented in any way.
: The authors declare that they have no competing interests.