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Updated: Aug 14, 2026
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Subjective Refraction Test Using a Smartphone for Vision Screening
Published on: October 18, 2024
Smartphone Near-Viewing Demands Differ in Corrected Presbyopes: Implication for Presbyopic Correction
Carl Halladay Abraham1, Alhassan Osman2, Godfred Sakyi-Badu1
1School of Optometry and Vision Science, University of Cape Coast, Cape Coast, Ghana.
Summary
Presbyopes using smartphones require larger font sizes, longer viewing distances, and more time for reading tasks compared to non-presbyopes. This indicates increased visual effort and adaptation for near digital tasks.
Area of Science:
- Ophthalmology and Vision Science
- Human-Computer Interaction
- Ergonomics
Background:
- Presbyopia, the age-related loss of accommodation, affects near vision.
- Smartphone usage is prevalent across all age groups, including those with presbyopia.
- Understanding visual adaptations during smartphone use is crucial for ergonomic and visual health.
Purpose of the Study:
- To compare near viewing modifications during smartphone reading tasks between corrected presbyopes and non-presbyopes.
- To objectively assess differences in font size, viewing distance, and posture.
- To evaluate the impact of presbyopia on smartphone interaction efficiency.
Main Methods:
- Cross-sectional study design.
- Participants: corrected presbyopes and non-presbyopes.
- Standardized smartphone reading tasks with objective measurements of viewing distance, craniovertebral angle, and task completion time.
Main Results:
- Corrected presbyopes used significantly larger font sizes (p<0.01).
- Presbyopes maintained significantly greater viewing distances (p<0.001) and required longer task completion times (p<0.001).
- No significant difference in craniovertebral angle was observed between groups (p>0.05).
Conclusions:
- Corrected presbyopes exhibit increased visual effort and adaptation during smartphone use.
- Findings highlight the need for personalized presbyopic correction considering individual visual tasks.
- Prescribers should account for real-world smartphone usage demands beyond the conventional 40cm near working distance.
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