Back to Journals » Clinical Optometry » Volume 9

The prevalence and causes of decreased visual acuity – a study based on vision screening conducted at Enukweni and Mzuzu Foundation Primary Schools, Malawi

Authors Thom L, Jogessar S, McGowan SL, Lawless F

Received 7 April 2016

Accepted for publication 29 August 2016

Published 19 December 2016 Volume 2017:9 Pages 1—10


Checked for plagiarism Yes

Review by Single anonymous peer review

Peer reviewer comments 2

Editor who approved publication: Mr Simon Berry

Video abstract presented by Leaveson Thom

Views: 227

Leaveson Thom,1 Sanchia Jogessar,1,2 Sara L McGowan,1 Fiona Lawless,1,2

1Department of Optometry, Mzuzu University, Mzuzu, Malawi; 2Brienholden Vision Institute, Durban, South Africa

Aim: To determine the prevalence and causes of decreased visual acuity (VA) among pupils recruited in two primary schools in Mzimba district, northern region of Malawi.
Materials and methods: The study was based on the vision screening which was conducted by optometrists at Enukweni and Mzuzu Foundation Primary Schools. The measurements during the screening included unaided distance monocular VA by using Low Vision Resource Center and Snellen chart, pinhole VA on any subject with VA of less than 6/6, refraction, pupil evaluations, ocular movements, ocular health, and shadow test.
Results: The prevalence of decreased VA was found to be low in school-going population (4%, n=594). Even though Enukweni Primary School had few participants than Mzuzu Foundation Primary School, it had high prevalence of decreased VA (5.8%, n=275) than Mzuzu Foundation Primary School (1.8%, n=319). The principal causes of decreased VA in this study were found to be amblyopia and uncorrected refractive errors, with myopia being the main cause than hyperopia.
Conclusion: Based on the low prevalence of decreased VA due to myopia or hyperopia, it should not be concluded that refractive errors are an insignificant contributor to visual disability in Malawi. More vision screenings are required at a large scale on school-aged population to reflect the real situation on the ground. Cost-effective strategies are needed to address this easily treatable cause of vision impairment.

Keywords: vision screening, refractive errors, visual acuity, Enukweni, Mzuzu foundation

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF]  View Full Text [HTML][Machine readable]