Su, C. (Contributor), Hors-Fraile, S. (Creator), Syed-Abdul, S. (Creator), Spachos, D. (Creator), Bamidis, P. (Creator), Li, Y. (Contributor), Jeng, W. (Creator), Malwade, S. (Contributor), Fernandez-Luque, L. (Creator) (2018). Additional file 3: of A recommender system to quit smoking with mobile motivational messages: study protocol for a randomized controlled trial. Figshare. 10.6084/m9.figshare.7324691.v1