title: Shedding light on the shortness of sight
title: Myopia prevalence among school students and the usage of light meters in the study of light-myopia associations
titleType: AlternativeTitle
Creators: name: Hönekopp, Astrid
Publisher: name: TU Dortmund
Year: 2024
Subjects: subject: Myopia
subject: Short-sightedness
subject: Light exposure
subject: School myopia
subject: Myopia prevalence
subject: Refractive error
subject: Light meters
subject: Myopie
subject: Kurzsichtigkeit
subject: Lichtexposition
subject: Schulmyopie
subject: Myopieprävalenz
subject: Refraktionsfehler
subject: Lichtmesser
subject: 360
subject: 370
subject: Kurzsichtigkeit
subject: Licht
subject: Schüler
subject: Schülerin

description: The global rise in myopia prevalence sets off certain alarm bells, as myopia not only imposes a substantial economic and financial burden on affected individuals and the public, but can also entail further negative consequences, such as secondary pathologies as well as reduced quality of life and educational outcomes. The development of the most common type of myopia is connected to both school age as a critical period and bright light exposure as a key protective factor. Accordingly, timely public health interventions need up-to-date information on myopia prevalence and its associations, as well as the relationship with bright light exposure, which is often investigated with wearable light meters. This dissertation addresses in six studies three main research objectives to fill crucial gaps in myopia research: (1) providing up-to-date myopia prevalence data for German youth, (2) evaluating the utility of online questionnaires in epidemiological research, and (3) advancing methodological understanding of light meter use in myopia research. In Study 1, refractive measurements of &gt; 1,500 school students in Germany revealed a myopia prevalence of 8.4% in primary school students (mean age 9.30 years) and 19.5% in secondary school students (mean age 14.99 years) as well as a large proportion of uncorrected myopia (51.2% and 43.3%, respectively). Study 2 evaluated five recruitment strategies for an online parent questionnaire on children’s spectacle ownership, identifying varying (dis)advantages per strategy related to aspects such as representativeness, efficiency and costs. Study 3 analyzed the questionnaire data from &gt; 1,700 children, demonstrating discrepancies in prevalence rates of corrected myopia compared to direct measurements, thereby indicating biases in the questionnaire data. A comprehensive literature review in Study 4 examined the use of various wearable light meters in myopia research, revealing significant variability in device specifications and research methodologies, which likely contributes to inconsistent findings in the field. Study 5 directly compared the performance of multiple light meters worn simultaneously, showing similar light exposure patterns but substantial differences in absolute lux values and in the frequently investigated distinction of indoor and outdoor environments. Study 6 explored the development of a custom-made light meter, concluding that while feasible, commercial devices may be more practical for most research needs. This dissertation’s findings highlight the necessity for continuous monitoring of myopia prevalence, especially uncorrected myopia, and emphasize the importance of methodological rigor in research on light exposure and myopia. Recommendations include routine refractive screenings in schools and careful consideration of light meter selection and methodology in future studies on light-myopia associations. These insights address both future research efforts as well as public health strategies aiming at myopia.