Published on in Vol 20, No 5 (2018): May
Preprints (earlier versions) of this paper are
available at
https://preprints.jmir.org/preprint/9276, first published
.

1 Care and Public Health Research Institute, Department of Health Promotion, Maastricht University, Maastricht , NL
2 Care and Public Health Research Institute, Department of Methodology & Statistics, Maastricht University, Maastricht , NL
3 Amsterdam School of Communication Research, Department of Communication Science, University of Amsterdam, Amsterdam , NL