[Reproducibility of subjective refraction measurement]

Area of Science:

• Ophthalmology
• Optometry
• Vision Science

Background:

• Subjective refraction measurement reproducibility is influenced by method, subject, and examiner factors.
• Previous studies on refraction reproducibility lack standardization, hindering direct comparison.
• Understanding these factors is crucial for accurate vision assessment.

Purpose of the Study:

• To investigate the reproducibility of subjective refraction measurement in healthy eyes.
• To quantify the variability in repeated subjective refraction measurements.
• To establish the limitations of subjective refraction accuracy.

Main Methods:

• Conducted repeated subjective refraction measurements on healthy participants.
• Analyzed deviations from the mean value for spherical equivalent and cylindrical power.
• Compared findings with existing literature where possible.

Main Results:

• Ninety-five percent of deviations from the mean were within ±0.2 D to ±0.65 D for spherical equivalent and cylindrical power.
• Subjective refraction reproducibility is limited, even under ideal measurement conditions.
• Significant individual variability was observed in repeated measurements.

Conclusions:

• Accurate assessment of refraction requires identifying and accounting for individual variability.
• Multiple subjective refraction measurements are essential for reliable results.
• A defined tolerance range is inherent to subjective refraction measurements.