Effect of distant-image screen technology (DIST) on delaying myopia onset in pre-myopia children: study protocol for a1-year randomized controlled trial

BACKGROUND: Myopia is an escalating global health issue, particularly among adolescents, and its increasing prevalence is associated with a rising burden of ocular complications that adversely affect quality of life and strain healthcare resources. Extensive evidence links prolonged near work to myopia progression, prompting the development of innovative control strategies. One promising approach is the distant-image screen (DIST), which transforms a nearby real image into a virtual one that appears much farther away, thereby reducing the accommodative stress typically induced by prolonged near work. This study is designed to evaluate the efficacy of DIST in delaying the onset of myopia among pre-myopic children. METHODS: This is a 1-year, multi-arm randomized controlled trial involving 192 children, who will be randomly assigned in a 1:1:1 ratio to one of three groups: (1) a DIST group; (2) a Combined Intervention group, which will receive both DIST and an optical defocusing intervention; and (3) a control group, engaging in regular near work without the use of DIST. The primary objective is to assess whether the use of DIST-alone or in combination with optical defocusing-can effectively delay the onset of myopia in pre-myopic children. The primary outcome is the proportion of myopia onset, and the secondary outcomes are the proportion of fast myopia progressors, change in spherical equivalent progression, and change in axial length at each follow-up point. DISCUSSION: The study aims to determine the independent efficacy of DIST as well as its potential synergistic benefits when combined with optical defocusing techniques. In the context of increasing academic demands and near work exposure, DIST offers a space-efficient, practical solution that could alleviate visual strain without interfering with learning. By providing robust data on both refractive and ocular structural changes, the findings may inform personalized myopia prevention strategies. If successful, DIST could serve as a valuable adjunct to current myopia control methods, ultimately reducing the public health burden of myopia. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR), ChiCTR2400082078. Registered on 20 March 2024. https://www.chictr.org.cn/showproj.html?proj=221835.