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Updated: Nov 7, 2025

Subjective Refraction Test Using a Smartphone for Vision Screening
Published on: October 18, 2024
[Optometric eye screening in schools : First results of a pilot project on logistical feasibility]
Hakan Kaymak1,2, Kai Neller3,4, Saskia Funk3,4
1Institut für Experimentelle Ophthalmologie, Universitätsklinikum des Saarlandes UKS, Homburg/Saar, Deutschland. dr.h.kaymak@gmail.com.
Background:
We present a pilot project to improve eye health in schoolchildren: annual optometric screening with a focus on early detection of school myopia. The logistical proof-of-concept is illustrated by way of a pilot project at a state high school in North Rhine-Westphalia. The collected biometric parameters also contribute to the collection of epidemiological data.
Material And Methods:
On organized examination days objective and subjective refractions of schoolchildren in grades 5-7 (ages 9-16 years) were determined, children were tested for abnormalities in binocular vision and the photopic and mesopic pupil diameters were determined. Noncontact biometry was used to measure the corneal radius, central corneal thickness, anterior chamber depth, lens thickness and axial length of the eyes. Optical coherence tomography (OCT) was used to also determine the central choroidal thickness of the eyes. Questionnaires were employed to inquire about the visual habits of the schoolchildren.
Results:
In the fall of 2019 a total of 274 schoolchildren (11.2 ± 1.2 years) voluntarily participated in the examinations: 22% (61) showed myopia (spherical equivalent ≤ -0.50 D), of which 11% (7) were previously uncorrected (uncorrected distance visual acuity < 0.8). Of the schoolchildren 8% (5) showed an increase in myopia of more than -0.5 D compared to their actual spectacle values (distance visual acuity with ophthalmic lens < 0.8). A class of about 25 pupils can be examined within 2 regular periods.
Conclusion:
There is an actual need for optometric screening because a total of 4.4% (12) myopic schoolchildren could be identified who had a distance visual acuity of less than 0.8 even with the correction. By determining the axial length and classifying this value depending on age in the literature can help to predict the individual risk of myopia and to raise awareness among parents and children to address this problem. The planned repetition of these examinations enables a better understanding of eye growth in schoolchildren.

