The Pakistan National Blindness and Visual Impairment Survey ...

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The Pakistan National Eye Survey Study Group∗. ABSTRACT Purpose: To establish age- and sex-specific prevalence rates and causes of blindness and low ...
Ophthalmic Epidemiology, 12:321–333, 2005 c Taylor & Francis Inc. Copyright  ISSN: 0928-6586 DOI: 10.1080/09286580500230948

ORIGINAL ARTICLE

The Pakistan National Blindness and Visual Impairment Survey—Research Design, Eye Examination Methodology and Results of the Pilot Study Rupert Bourne Clinical Research Unit, Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, and Department of Epidemiology and International Eye Health, Institute of Ophthalmology, University College London & Moorfields Eye Hospital, London, England Brendan Dineen Clinical Research Unit, Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, England Zahid Jadoon Pakistan Institute of Community Ophthalmology, Khyber Institute of Ophthalmic Medical Sciences, Peshawar, Pakistan Pak S. Lee Department of Epidemiology and International Eye Health, Institute of Ophthalmology, University College London & Moorfields Eye Hospital, London, England Aman Khan Pakistan Institute of Community Ophthalmology, Khyber Institute of Ophthalmic Medical Sciences, Peshawar, Pakistan Gordon J. Johnson Allen Foster Clinical Research Unit, Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, England Daud Khan Pakistan Institute of Community Ophthalmology, Khyber Institute of Ophthalmic Medical Sciences, Peshawar, Pakistan The Pakistan National Eye Survey Study Group∗

ABSTRACT Purpose: To establish age- and sex-specific prevalence rates and causes of blindness and low vision in children aged 10 to 15 years and adults aged 30 years and older in Pakistan. Methods: Multi-stage, stratified (rural/urban), cluster random sampling, with probability proportional-to-size procedures, was utilised to select a cross-sectional, nationally representative sample of adults (16,600 subjects) and children (6,000 subjects). Each subject underwent: interview, visual acuity (logMAR), autorefraction and optic disc examination. Those that saw