Text and Data Mining valid from 2019-02-07
First Online: 7 February 2019
Compliance with ethical guidelines
: N. Vonderlin, J. Siebermair, E. Kaya, M. Köhler, T. Rassaf, and R. Wakili declare that they have no competing interests.
: This article does not contain any studies with human participants or animals performed by any of the authors.