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Updated: Jul 10, 2026

Subjective Refraction Test Using a Smartphone for Vision Screening
Published on: October 18, 2024
The rationale for shifting from a voluntary clinical approach to a public health approach in addressing refractive
Jerry E Vincent1, Matthew G Pearce, Janet Leasher
1International Rescue Committee, Health Unit, Chiang Mai, Thailand. jvincent@loxinfo.co.th
Abstract:
Millions of people need eyeglasses and do not have them. Assuming that the average pair of eyeglasses has an effective life span of two to five years, an additional 60 to 150 million spectacles would be needed each year for the estimated 303 million individuals who currently need correction. Optometrists are engaged in a variety of capacities in an attempt to address the significant public health problem of uncorrected refractive error. One popular method used by many voluntary optometry-led organisations is to provide direct clinical services to individual patients in developing countries. Considerable manpower, materials, money and logistical resources are used in conducting these short-term missions, yet scarce evidence exists regarding their cost effectiveness or the efficacy and long-term impact of these interventions. The provision of direct clinical services by most foreign volunteers does not directly build local capacity and may hinder development of sustainable local services. Adopting public health approaches will enable volunteer provider organisations to dramatically increase their program effectiveness and output, while developing local capacities in a sustainable way. These approaches should include: 1. Following the national strategy for blindness prevention as determined by the Ministry of Health and forming partnerships with relevant local, national and international organisations. 2. Using need-based criteria to target programs more efficiently. 3. Developing sustainable services via local capacity building. 4. Monitoring, evaluating and using evidence to guide programs. By using these approaches, a larger contribution will be made by the volunteer organisations in addressing the unmet need for refractive correction.
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