Published on in Vol 20, No 7 (2018): July
Preprints (earlier versions) of this paper are
available at
https://preprints.jmir.org/preprint/9923, first published
.
1 Center for eHealth and Wellbeing Research, Department of Psychology, Health and Technology, University of Twente, Enschede, Netherlands
2 Optentia Research Focus Area, North-West University, Vanderbijlpark, South Africa