The number of people identified with diabetes in England increased by nearly 5% during 2011-2012 to well over 2.5 million. During 2011-2012 the NHS Diabetic Eye Screening Programme screened more than 1.9 million people. In general, the UK is doing very well with its DR screening targets. It is a world leader in diabetic retinopathy screening, having offered 85.7% of eligible diabetic patients the screening programme. However, the target is 100% and efforts are still being made to improve screening locally. Our aim is to evaluate the prevalence of sight-threatening diabetic retinopathy (STDR) (proliferative retinopathy or maculopathy), the number of patients needing laser treatment or vitrectomy and registered blind in the last 12 months in a defined population. We did a twelve-month retrospective database review at the Systematic Diabetic Retinopathy Screening Service at Wirral University Hospital Trust, United Kingdom. The effectiveness of different screening modalities has been widely investigated. UK studies show sensitivity levels for the detection of sight-threatening diabetic retinopathy of 41%-67% for general practitioners, 48%-82% for optometrists, 65% for ophthalmologists, and 27%-67% for diabetologists and hospital physicians using direct ophthalmoscopy. Sensitivity for the detection of referable retinopathy by optometrists have been found to be 77%-100%, with specificity of 94%-100%. Photographic methods currently use digital images with subsequent grading by trained individuals. Sensitivity for the detection of sight-threatening diabetic retinopathy have been found 87%-100% for a variety of trained personnel reading mydriatic 45° retinal photographs, with specificities of 83%-96%. The British Diabetic Association (Diabetes UK) has established standard values for any diabetic retinopathy screening programme of at least 80% sensitivity and 95% specificity. We used descriptive analyses to characterise the study population and patterns of diabetic retinopathy, and used t tests and χ(2) tests to explore differences between patients without any retinopathy and those who developed any, background, or referable retinopathy. Parametric survival analysis with covariates identified those factors associated with the development of referable retinopathy. The presence of diabetic retinopathy was determined after each screening event during the study period. Although intended to occur annually, screening took place at variable times during the one year period. Of known diabetics in a total population 325.000, 84% accessed screening and 15.196 (4.7%) were screened. 748 were referred with referable retinopathy. 16% of the patients needed laser treatment for the first time, 30 patients needed vitrectomy, and 16 were registered blind. To evaluate the effectiveness of diabetic retinopathy screening (DRS) service we did a retrospective comparative analysis of 2 year DRS data in Wirral (2010-2012). An increase of 6.8% in the number of diabetics was noted over the last 12 months compared to the previous period. Referable retinopathy decreased from 5.6% for 2010-2011 to 4.94% during the same period in 2011-2012. In particular, the incidence of proliferative retinopathy (R3) has dropped from 0.7% last year to 0.52% this year. STDR has significant impact on ophthalmic services, but a well-implemented program provides timely treatment, reducing the need for vitrectomy and blind registration and serving as a benchmark to plan service delivery in a similar population.