Effectiveness of screening and monitoring tests for diabetic retinopathy -a systematic review

Aims To determine which screening and monitoring tests for diabetic retinop athy are most effective and under what circumstances. Methods A systematic review of the English language literature, published f rom 1983 to April 1999. Results Available studies are generally limited in their ability to answer the important questions on the effectiveness of tests for early detection o f diabetic retinopathy. No randomized controlled trials were identified alt hough primary studies exist for two screening tests: ophthalmoscopy, either direct or indirect, and retinal photography, using either mydriasis or non -mydriasis. Retinal photography under mydriasis appears to be the most effe ctive test, with the majority reporting levels of sensitivity in excess of 80%. However effectiveness is compromised when photographs are ungradable. Ophthalmoscopy can also reach acceptable standards of sensitivity and speci ficity. Conclusion Based on an assessment of available cohort studies, the most eff ective strategy for testing is the use of mydriatic retinal photography wit h the additional use of ophthalmoscopy for cases where photographs are ungr adable. This does not exclude the use of ophthalmoscopy alone for opportuni stic case finding but there is evidence of considerable variation in effect iveness of this test.