Providing full screening of diabetic patients for retinopathy throughout the community would significantly reduce the incidence of blindness in this group of patients. However, although panretinal photocoagulation is of proved value in reversing or preventing neovascular complications and careful macular treatment prevents further visual loss, the resources or the infrastructure to detect appropriate patients for treatment are not universally available.1 The importance of the situation has been highlighted by the declaration of St Vincent, a European directive on the need to provide screening.2 3 An effective screening and treatment programme would ultimately reduce the burden on health and social service budgets because fewer of these relatively young patients would require long term support.4-6

Locally based efforts indicate that the key to diabetic retinopathy screening is efficiently obtaining images of the retina for classification. This raises two problems—firstly, the target population must be reached at minimum inconvenience to the patient and, secondly, the images must be assessed effectively. Care facilities for diabetic patients are spread throughout the community and so it is …