Schönenberg, D.
Guggenberger, R.
Frey, D.
Pape, H.-C.
Simmen, H.-P.
Osterhoff, G.
Article History
Received: 27 July 2017
Accepted: 6 November 2017
First Online: 13 November 2017
Compliance with ethical standards
: The protocol of the present study was approved by the local ethics committee (Kantonale Ethik-Kommission Zürich, KEK-ZH-Nr. 2016–01758).
: None.