Comparison of refractometric measurements obtained with a portable autorefractor and conventional methods of refraction in schoolchildren

Comparação de medidas refratométricas obtidas com autorrefrator portátil e métodos convencionais de refração em escolares

ABSTRACT

Objective:

To assess the performance of a portable autorefractor as refractor and screening tool for refractive errors in schoolchildren.

Methods:

Cross-sectional observational study. Refractometric measurements of children between 5 and 10 years old were obtained through four methods: 2WIN under non-cycloplegic conditions, and 2WIN, conventional autorefractor, and retinoscopy, under cycloplegic conditions. Correlations and agreement between the methods and accuracy of the portable autorefractor to define whether to prescribe glasses were assessed.

Results:

The mean age ± standard deviation was 6.87 ± 1.42 years. The portable autorefractor without cycloplegia showed a high correlation with retinoscopy (0.77) but tended to underestimate hyperopia and overestimate high astigmatism. Regarding screening for prescription of glasses in comparison with the reference method “retinoscopy,” the sensitivity of the portable autorefractor without cycloplegia was calculated to be 100,00% and the specificity, 34.3%.

Conclusion:

The portable autorefractor should be used as a screening tool and, when prescribing glasses, the tendency of underestimating hyperopia and overestimating high astigmatism should be kept in mind.

Keywords:
Ocular refraction; Refractive errors; Retinoscopy; Photoscreening; Autorefractor; Portable refractor