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Updated: Jul 5, 2025

Subjective Refraction Test Using a Smartphone for Vision Screening
Published on: October 18, 2024
Near vision data and near correction requirements from community eye health programmes in nine countries
Marzieh Katibeh1,2, Elanor Watts3,4, Michael Gichangi5
1Peek Vision, Berkhamsted, UK.
Background:
Recent estimates of global prevalence of uncorrected presbyopia range from 510 to 826 million. There is a shortage of primary data regarding Near Visual Impairment (NVI) magnitude.
Methods:
Near visual acuity (NVA) and NVI data was collected from over 388,000 people aged 35 or over across 9 countries, within Community Eye Health programmes between January 2022 and June 2023. In Kenya (n = 34,328), dioptric power of required near correction was also recorded, and any association with age, gender or level of NVA was assessed via linear regression model.
Results:
146,801 of 388,939 people failed initial near vision screening (37.74%, 95% CI 37.59-37.89%), with significantly higher prevalence of NVI in Sub-Saharan Africa than South Asia. Of those with distance acuity 6/12 or better, 27.97% failed (95% CI 27.81-28.13%) with evidence of difference between genders (p < 0.001): 30.77% of women vs. 24.47% of men. The most commonly required dioptric powers of correction were +2.00D, +2.50D and +3.00D, and required power correlated with age and NVA.
Conclusions:
NVI remains common among Community Eye Health programme participants aged 35 and over. Data from large scale programmes such as these provide an opportunity to contribute to more accurate epidemiological estimates, and to guide future research, resource planning and intervention, ideally with improved standardisation of testing in the future.
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