Text and Data Mining valid from 2020-01-07
Received: 26 November 2019
Accepted: 30 December 2019
First Online: 7 January 2020
Ethics approval and consent to participate
: This study was approved by the institutional review board (Business Administration System for Ethics Committees, BASEC, No. 2018–00146).
: Not applicable.
: The authors declare that they have no competing interests.