Published on in Vol 6, No 6 (2018): June
Preprints (earlier versions) of this paper are
available at
https://preprints.jmir.org/preprint/10409, first published
.
1 Department of Preventive Medicine and Public Health, School of Medicine, University of Seville, Seville, Spain
2 Mutua Balear, Seville, Spain
3 Virgen Macarena University Hospital, Seville, Spain