Currently, a large part of the world population does not have access to quality visual health services. Most of this population lives in developing countries, thus it is necessary to screen the general population to identify ocular abnormalities such as refractive errors and amblyopia in schoolchildren. The protocols for complete visual screening or examination vary widely regarding the type of tests and procedures, although most of them use visual acuity (VA) and refraction as the main diagnostic criteria. These clinical tests should have good quality and precision, that is, a high sensitivity and specificity. Unfortunately, in most clinical and epidemiological studies, the quality and accuracy of the tests used are unknown, which makes it difficult to compare results and to estimate the real conditions of visual problems in the population. Therefore, the objective of this literature review was to describe the main tests and protocols used in epidemiological and clinical studies for the detection of refractive errors in children.

<em><strong>Objective</strong><em> To quantify the ocular biometric parameters, the corneal biomechanical properties, the anatomical configuration of the optic nerve and the retinal nerve fiber layer (RNFL) in a group of children through non-invasive techniques. <em><strong>Material and methods</strong><em> A cross-sectional, descriptive and non-randomized study was conducted in 293 healthy Caucasian children between the ages of 6 and 17. The subjects were divided according to refractive error. <em><strong>Results</strong><em> A statistically significant correlation was found between axial length (AL) and corneal hysteresis (CH) (p < 0.001). CH decrease was also found with increasing myopia, and CH increase with increasing hypermetropia (p < 0.001). In the posterior segment, a positive correlation was found between the average thickness of the RNFL and the CH (p = 0.01). Likewise, a decrease in the average thickness of the RNFL was observed with the increased AL (p < 0.001) and myopia (p < 0.0001). <em><strong>Conclusions</strong><em> The mechanical strength of the anterior segment of the eye is affected in myopic subjects at early ages and in severe myopia, regardless of age. Lower CH values, in addition to a reduction in the corneal viscoelastic damping capacity, indicate the existence of a more easily deformable optic nerve, together with a thinning of the RNFL, especially in myopic children. This study provides normal values of these parameters and makes it possible to correlate them with refractive errors.