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Subjective versus objective refraction in healthy young adults
Yuval Kozlov1,2, Michael Kinori3,4, Sharon Armarnik5
1Department of Military Medicine, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel.
BMC Ophthalmology
|February 20, 2024
Summary
Objective and subjective refraction in young adults showed differences, with participants preferring less correction for myopia and hyperopia. Older individuals favored less astigmatism correction compared to autorefraction measurements.
Area of Science:
- Ophthalmology
- Optometry
- Vision Science
Background:
- Refractive error assessment is crucial for vision correction.
- Autorefractors provide objective measurements, while subjective refraction refines the prescription.
- Understanding discrepancies between objective and subjective refraction is vital for accurate eye care.
Purpose of the Study:
- To compare objective and subjective refraction measurements in healthy young adults.
- To analyze differences in spherical equivalent (SE), cylinder power (Cp), and astigmatic axis between autorefraction and subjective refraction.
- To identify patterns in refractive preferences among myopic, hyperopic, and older participants.
Main Methods:
- Retrospective analysis of 1,395 young adults undergoing routine eye exams.
- Comparison of autorefractor (objective) and optometrist (subjective) refraction data.
- Conversion of results to power vectors (SE, J0, J45) and calculation of cylinder power (Cp).
Main Results:
- Significant differences were found in SE (p=0.001) and Cp (p<0.001) between objective and subjective refraction.
- Young hyperopic participants preferred less plus power, while myopic participants preferred less minus power.
- Older participants and the overall cohort showed a preference for less cylinder power (Cp) in subjective refraction.
Conclusions:
- Subjective refraction reveals a tendency for young adults to undercorrect myopia and hyperopia.
- Participants, particularly older ones, preferred reduced astigmatism correction compared to objective measurements.
- Astigmatic axis measurements were consistent between objective and subjective methods.
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