Text and Data Mining valid from 2018-04-02
Received: 17 December 2017
Accepted: 21 March 2018
First Online: 2 April 2018
Compliance with ethical standards
: T. Draeger, V. Völkel, M. Gerken, M. Klinkhammer-Schalke, and A. Fürst declare that they have have no conflicts of interest or financial ties to disclose.
: This article does not contain any studies with human participants or animals performed by any of the authors.