Steiner, K. M.
Thier, W.
Batsikadze, G.
Ludolph, N.
Ilg, W.
Timmann, D.
Article History
Received: 11 October 2019
Revised: 10 January 2020
Accepted: 13 January 2020
First Online: 31 January 2020
Compliance with ethical standards
:
: None.
: All participants gave their oral and written informed consent to take part in this study. The study was approved by the local ethics committee of the medical faculty of the University Duisburg-Essen and was conducted in accordance to the Declaration of Helsinki.