Incidence and progression of diabetic retinopathy in Sub-Saharan Africa: A five year cohort study. - Burgess, Philip I.; Harding, Simon P.; García-Fiñana, Marta; Beare, Nicholas A. V.; Glover, Simon; Cohen, Danielle B.; Msukwa, Gerald; Allain, Theresa J. (PLoS ONE, 2017)