The Pakistan National Blindness and Visual Impairment Survey-research design, eye examination methodology and results of the pilot study.


Bourne, R; Dineen, B; Jadoon, Z; Lee, PS; Khan, A; Johnson, GJ; Foster, A; Khan, D; (2005) The Pakistan National Blindness and Visual Impairment Survey-research design, eye examination methodology and results of the pilot study. Ophthalmic epidemiology, 12 (5). pp. 321-33. ISSN 0928-6586 DOI: https://doi.org/10.1080/09286580500230948

Full text not available from this repository.

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 < 6/12 in either eye underwent corrected visual acuity and dilated posterior segment examination. Results: The results of a pilot survey are reported in this paper. In the two rural pilot sites, 159 subjects (including 47 children) were examined; 50% were male. Thirty seven adults (23.3%) but no children saw worse than 6/12 in either eye. Two subjects were blind (corrected visual acuity) in the better eye, and 11 were visually impaired. Refractive error was the main cause (in 22 eyes (39% of the total of 56 eyes)) of < 6/12 visual acuity, followed by cataract (12 eyes), uncorrected aphakia (6 eyes) and age-related macular disease (3 eyes). Conclusions: The pilot survey demonstrated that the proposed examination process for the main survey is feasible. Particular strengths of this survey include the use of logMAR visual acuity testing and autorefraction of all subjects, a dilated posterior segment examination, and the use of a 'less than 6/12' threshold for further examination. This lower threshold addresses the burden of refractive error, which, with cataract, are two of the diseases specifically targeted by Vision 2020.The Pakistan National Eye Survey Study Group*

Item Type: Article
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
PubMed ID: 16272052
Web of Science ID: 232465300006
URI: http://researchonline.lshtm.ac.uk/id/eprint/12501

Statistics


Download activity - last 12 months
Downloads since deposit
0Downloads
277Hits
Accesses by country - last 12 months
Accesses by referrer - last 12 months
Impact and interest
Additional statistics for this record are available via IRStats2

Actions (login required)

Edit Item Edit Item