The effect of an interactive weekly mobile phone messaging on retention in prevention of mother to child transmission (PMTCT) of HIV program: study protocol for a randomized controlled trial (WELTEL PMTCT). - Patricia Opondo Awiti; Alessandra Grotta; Mia van der Kop; John Dusabe; Anna Thorson; Jonathan Mwangi; Rino Belloco; Richard Lester; Laura Ternent; Edwin Were; Anna Mia Ekström (BMC Medical Informatics Decis. Mak., 2016)