van der Kop, M., Muhula, S., Nagide, P., Thabane, L., Gelmon, L., Awiti, P., … Lester, R. (2018). Effect of an interactive text-messaging service on patient retention during the first year of HIV care in Kenya (WelTel Retain): an open-label, randomised parallel-group study. The Lancet. Public Health. https://doi.org/10.1016/S2468-2667(17)30239-6 (Original work published 2018)