Refractive Error in Nigerian Adults: Prevalence, Type, and Spectacle Coverage

Ezelum, C; Razavi, H; Sivasubramaniam, S; Gilbert, CE; Murthy, GVS; Entekume, G; Abubakar, T; Nigeria Natl Blindness, V; (2011) Refractive Error in Nigerian Adults: Prevalence, Type, and Spectacle Coverage. Investigative ophthalmology & visual science, 52 (8). pp. 5449-5456. ISSN 0146-0404 DOI:

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PURPOSE. To provide data on prevalence and types of refractive error and the spectacle-wearing rate among adults in Nigeria and the degree to which the need for distance correction could be met by off-the-shelf spectacles. METHODS. Multistage, stratified, cluster random sampling with probability proportional to size was used to identify a nationally representative sample of 15,027 persons aged >= 40 years. Distance vision was measured using a reduced logMAR tumbling-E chart. All participants underwent autorefraction, and those with presenting acuity of <6/12 in one or both eyes had their corrected acuity measured and underwent detailed clinical examination to determine the cause. RESULTS. Included in the survey were 13,599 (89.9%) of the 15,122 persons aged >= 40 years who were enumerated. Uncorrected refractive error was responsible for 77.9% of mild visual impairment (<6/12-6/18), 57.1% of moderate visual impairment (<6/18-6/60), 11.3% of severe visual impairment (<6/60-3/60), and 1.4% of blindness (<3/60). The crude prevalence of myopia (<= 0.5 D) and high myopia (<= 5.0 D) were 16.2% and 2.1%, respectively. Spectacles could improve the vision of 1279 (9.4%) and 882 (6.5%) participants at the 6/12 and 6/18 level, respectively, but only 3.4% and 4.4% of these individuals wore spectacles to the examination site. Approximately 2,140,000 adults in Nigeria would benefit from spectacles that improved their vision from <6/12 to >= 6/12. More than a third of the need could be met by low-cost, off-the-shelf spectacles. CONCLUSIONS. Uncorrected refractive errors are an important cause of visual impairment in Nigeria, and services must be dramatically improved to meet the need. (Invest Ophthalmol Vis Sci. 2011; 52: 5449-5456) DOI: 10.1167/iovs.10-6770 DU L, 2002, V11, P108

Item Type: Article
Keywords: visual impairment survey, beaver dam eye, blue mountains eye, national, blindness, risk-factors, older population, barbados eye, bangladesh, singapore, cataract
Faculty and Department: Faculty of Infectious and Tropical Diseases > Dept of Clinical Research
Research Centre: The International Centre for Evidence in Disability
International Centre for Eye Health
Centre for Global Non-Communicable Diseases (NCDs)
PubMed ID: 21330658
Web of Science ID: 293377400057


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