Comparison of Self-Test Refraction, Autorefraction, and Subjective Refraction

To compare the performance of a self-refraction device (EyeQue Vision Check 2, EyeQue, USA) with autorefraction (OPD-Scan III, NIDEK) and subjective cycloplegic refraction in measuring refractive errors.

This descriptive study included 80 eyes from 40 patients. Measurements were obtained using the portable EyeQue device, OPD-Scan III, and subjective cycloplegic refraction performed by an experienced examiner. Spherical equivalent (SE), cylindrical power, and axis values were analyzed using power vector decomposition (M, J0, J45) to improve accuracy in comparing methods. The main outcome was the agreement between self-refraction, autorefraction, and subjective refraction.

The EyeQue device showed lower variability and greater homogeneity in spherical measurements but exhibited lower precision for cylindrical power and axis than subjective refraction. Power vector analysis revealed that EyeQue overestimated spherical equivalent (M) and produced higher J0 values, suggesting a tendency to alter cylindrical correction. Although comparable to OPD-Scan in spherical refraction, EyeQue demonstrated inconsistencies in astigmatism correction, particularly in J45 components.

The EyeQue device is a promising tool for large-scale screenings due to its affordability and portability. However, its limitations in astigmatism and axis measurements indicate that subjective refraction should complement rather than replace it. Therefore, further refinement and validation in diverse populations are recommended.