Text and Data Mining valid from 2019-01-25
Received: 16 June 2018
Accepted: 11 January 2019
First Online: 25 January 2019
Compliance with ethical standards
: The authors declare that they have no conflict of interest.
: Approval for this study was obtained from the VIFM Research Advisory Committee (RAC 008/17) and VIFM Human Research Ethics Committee (EC 06/2017).