COVID-19 vaccination advice via SMS-based video to improve vaccination uncertainty in at-risk groups. (June 2021) - Bateman, James; Cox, Natasha; Rajagopala, Lavanya; Ford, Mark; Jasim, Muhamad; Mulherin, Diarmuid; Venkatachalam, Srinivasan; Douglas, Barbara; Hirsch, George; Sheeran, Tom