Vision screening of older people

A recent systematic review found that between 20% and 50% of older people in the UK have undetected reduced vision and in most cases this is caused by refractive error or cataracts, and is correctable. Two approaches to improve the detection of these problems are to better publicise optometric services and to carry out community-based vision screening of older people. Screening programmes should pass the Wilson criteria and a consideration of these highlights three inter-related questions: 'Is vision screening effective at detecting correctable low vision in older people?'; 'Which tests should be included?' and 'Which venues are most appropriate?' We carried out a systematic review to investigate these questions. For the first question, only one study was found which met our selection criteria. The 'gold standard' eye examination in this study lacked several important components, and the vision screening method that was used was not found to be very effective. The review revealed other studies, which, although not meeting our selection criteria, included relevant information. The screening studies highlight the lack of agreement on the content of a gold standard eye examination and of the test(s) that should be used to screen vision. Visual function in older people is not adequately described by high contrast visual acuity (VA), nor by self-reports of visual difficulties. Other tests that may be relevant include visual field testing, low contrast VA, contrast sensitivity and stereo-acuity. The pinhole test has often been used in attempts to detect uncorrected refractive errors, but results from this test can be problematic and possible reasons for this are discussed. Appropriate venues for vision screening are contingent upon the format of the vision screening programme. There is still uncertainty over the battery of vision tests that are most appropriate. This, and optimum venues for screening, require further research before it can be fully determined whether vision screening of older people meets the Wilson criteria. If a vision screening programme using a battery of vision tests, perhaps computerised, can be established, then this should be tested to determine the sensitivity and specificity for detecting the target conditions. Ultimately, longitudinal studies are necessary to determine whether such a screening programme will lead to improved visual performance and quality of life in older people.