Aim: To report the usefulness of uncorrected distance visual acuity (DVA) at 16 years to “screen” for myopia status and to assess the lifetime risk of myopia, based on a national birth cohort.
Methods: 1867 members of the 1958 British birth cohort for whom there were data on acuity at 16 years had autorefraction, as part of a biomedical survey, at 45 years. Reduced uncorrected DVA at age 16 years (6/12 or worse in both eyes) was compared with adult refraction (spherical equivalent).
Results: Only a quarter of individuals in the population studied who had developed myopia by 45 years of age had reduced acuity at 16 years of age. Notably, half of all adults with moderate myopia (−2.99 to −5.99) and 31% (11/35) with severe myopia (⩾−6) had good uncorrected DVA in both eyes at 16 years of age. Thus, sensitivities were low, ranging from 16% for all myopia (cut-off point spherical equivalent −0.5) to 69% for severe myopia (cut-off point spherical equivalent −6). However, a high (91%) lifetime probability of primary myopia (spherical equivalent ⩾−0.5) given a reduced uncorrected DVA at 16 years was found.
Conclusion: In this population, reduced uncorrected DVA in childhood is an inaccurate and inappropriate intermediate “phenotype” for capturing adult myopia status. However, our findings support assessment of DVA in secondary school children as an effective method of identifying refractive error (both myopia and hypermetropia).
- PPV, positive predictive value
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Funding: The biomedical survey was funded by the Medical Research Council grant G0000934, awarded under the Health of the Public initiative. The Medical Research Council (MRC) had played no role in study design, collection, analysis and interpretation of data, writing the report, or submitting the paper for publication. The Great Ormond Street Hospital Special Trustees provided 10 Retinomax 2 autorefractors. PMC was supported by the BUPA Foundation and the MRC. Research at the Institute of Child Health and Great Ormond Street Hospital for Children NHS Trust benefits from R&D funding received from the NHS Executive.
Competing interests: None declared.
Published Online First 4 October 2006