Dropout rates among optical interventions for myopia control: a systematic review

Paper title: Dropout rates among optical interventions for myopia control: a systematic review

Authors: Santodomingo-Rubido J (1), Martínez-Pérez C (2), Villa-Collar C (3)

1. Global R&D, Menicon Co., Ltd, Nagoya, Japan
2. Applied Physics Department (Optometry Area), Facultade de Óptica e Optometría, Universidade de Santiago de Compostela, 15705 Santiago de Compostela, Spain
3. Faculty of Biomedical and Health Sciences, Universidad Europea, Madrid, Spain

Date: Published online January 1, 2026

Reference: Santodomingo-Rubido J, Martínez-Pérez C, Villa-Collar C. Dropout rates among optical interventions for myopia control: a systematic review. Cont Lens Anterior Eye. 2026 Jan 1;49(2):102601.

[Link to open access paper]

Clinical trials that investigate myopia control efficacy typically report participant involvement in detail. However, some studies fail to differentiate between withdrawal before and after treatment initiation, while others omit reasons for discontinuation altogether.

Discontinuation during myopia clinical trials may reflect a range of influences: some arise from issues intrinsic to the intervention, such as ocular symptoms or handling difficulties, while others are contextual, including relocation, scheduling barriers, or loss of motivation. High dropout can threaten a trial’s internal validity and limit generalisability, particularly if those who discontinue differ systematically from those who remain.

This is the first systematic review to evaluate dropout rates and reasons for discontinuation among spectacles, soft contact lenses, and orthokeratology in myopia control clinical trials involving children and adolescents. It aimed to clarify how real-world adherence may be influenced by the acceptability of each modality.

Key points were as follows:

• The analysis included 57 clinical trials representing a total of more than 7,000 years of combined participant follow-up. Dropout rates ranged from 6 to 21 per 100 children treated for one year, depending on modality.
• Spectacles had the lowest dropout rate (6.1 per 100 subject-years), followed by orthokeratology (13.9), and soft contact lenses showed the highest (21.3).
• The most common reasons for discontinuation were “unknown” (e.g., lost to follow-up, or not reported), followed by treatment compliance issues.
• Spectacle wearers were least likely to discontinue due to symptoms, appearance, or handling difficulties.
• Orthokeratology had more dropouts due to ocular adverse events; soft contact lenses had more dropouts with unknown causes.
• Control groups in these myopia studies had the same dropout as those in myopia control spectacles; less dropout than those in myopia control soft contact lenses; and more dropout than those wearing orthokeratology
• Modalities varied not only in overall dropout but also in the nature of reasons for discontinuation, suggesting different challenges in long-term adherence.

Understanding dropout patterns is essential when interpreting clinical trial data and applying it to real-world myopia management. This review highlights that adherence challenges vary meaningfully between optical interventions. Spectacle-based treatments, which had the lowest dropout, may be more acceptable for many families due to their familiarity, minimal handling demands, and lack of ocular contact. Soft contact lenses, while effective in slowing myopia progression, showed the highest discontinuation, potentially reflecting the behavioural and physiological demands of daily wear. Orthokeratology had moderate dropout, with ocular adverse events noted more frequently than in other modalities, and less dropout then comparative control groups.

Compliance has been shown to directly influence treatment effect, regardless of modality, and is shaped by comfort, vision quality, and ease of use. Equally important are safety, acceptability, and the ability of children and families to maintain treatment over time. These factors should be part of every myopia control discussion, especially when selecting a modality for younger or less motivated patients.

Importantly, high dropout in trials may signal potential barriers to long-term adherence in practice. Eye care professionals should prioritise early support, address handling challenges, and explore family preferences to improve persistence. Tailoring the modality to the child’s lifestyle and capacity is key to sustaining myopia control and maximising outcomes.

This review highlights key gaps in the way dropout is reported in paediatric myopia control trials. A significant proportion of discontinuations were attributed to “unknown” reasons, limiting insight into the specific challenges associated with each intervention. Future studies could use more consistent definitions to distinguish between pre-treatment withdrawal and true dropout and could also benefit from clearer categorisation of discontinuation reasons.

There is also value in exploring how dropout patterns vary across different groups, such as age, sex, or baseline myopia, to identify children who may be more likely to discontinue. The timing of dropout could be reported more consistently to help determine whether children are stopping early in treatment or after longer-term wear. Finally, it remains unclear how closely clinical trial dropout reflects real-world persistence with treatment. Understanding this link could help translate trial outcomes into more realistic expectations for long-term adherence in practice.

Background: Understanding adherence and discontinuation is essential for evaluating the real-world feasibility of myopia-control strategies. Although dropout is recognised as a concern in adult contact lens wear, its prevalence and causes in paediatric optical myopia-control interventions remain poorly characterised. This study systematically quantified dropout rates and examined reasons for discontinuation across optical modalities used for myopia control in children.
Methods: A systematic review was conducted in accordance with PRISMA and registered in PROSPERO (CRD420251177073). PubMed, Scopus, and Web of Science were searched through April 2025, supplemented by reference screening. Randomised and non-randomised clinical trials enrolling children and adolescents (≤18 years) and reporting discontinuations during optical myopia-control treatment were included. Data on study design, subject characteristics, dropout counts, subject-years, and reasons for discontinuation were extracted. Poisson regression with log-link and offset for subject-years estimated dropout rates with 95 % confidence intervals; Bonferroni-adjusted pairwise contrasts compared modalities.
Results: Fifty-seven trials met inclusion criteria (22 spectacles, 20 soft contact lenses, 17 orthokeratology), representing > 7,000 subject-years. Dropout ranged from 6 % to 21 % per year across modalities (p < 0.001), lowest for spectacles and highest for soft contact lenses. Reasons for dropout also differed significantly between modalities (p < 0.001). Spectacles showed markedly lower discontinuation due to "symptoms, vision, appearance, fitting/handling issues" and "unknown" reasons (both p < 0.05) but higher dropout for administrative/logistical "other" reasons versus contact lenses (p < 0.03). Soft contact lenses had lower discontinuation for "ocular adverse events" than orthokeratology but substantially higher discontinuation for "unknown" reasons (p < 0.001). No significant differences were found between modalities for treatment/compliance or non-ocular health reasons (p > 0.05).
Conclusions: Dropout in paediatric optical myopia-control interventions is modality-dependent, reflecting differences in handling burden, ocular tolerance, and follow-up demands. Standardised reporting of discontinuation reasons and structured adherence-support strategies are required to improve comparability across studies, enhance patient retention, and optimise real-world myopia-control outcomes.

[Link to open access paper]