Instrument-based, non-cycloplegic versus cycloplegic refraction in pediatric and young adult populations (≤25 years): A systematic review and meta-analysis.

Background: Accurate refractive assessment in children and young adults is critical to prevent amblyopia and strabismus, conditions that may arise from uncorrected hyperopia. Although non-cycloplegic autorefractors and photoscreeners are increasingly used for vision screening due to their practicality and high testability, residual accommodation often introduces systematic measurement bias. The debate regarding the necessity of cycloplegia has intensified, particularly in large-scale epidemiological studies and screening programs, highlighting the need for an evidence-based synthesis. Methods: This systematic review and meta-analysis, conducted according to PRISMA and AMSTAR-2 standards and registered in PROSPERO (CRD420251134665), synthesized data from 54 comparative studies, with 24 included in quantitative analyses. Results: Compared with cycloplegic reference methods, non-cycloplegic autorefractors and photoscreeners consistently underestimated refractive error, showing pooled mean differences of -0.65 D (95% CI: -0.84 to -0.45; 95% PI: -1.50 to +0.20 D) and -0.78 D (95% CI: -1.12 to -0.44; 95% PI: -1.70 to +0.10 D), respectively. These prediction intervals illustrate the wide variability expected across future studies and populations. The bias was most pronounced in younger children and hyperopic eyes, reflecting the impact of accommodative tone. Despite device-specific differences, no method fully corrected this systematic error. Testability exceeded 95% across most devices, reinforcing their feasibility for population-level screening. However, the certainty of evidence was rated as low due to heterogeneity and observational design limitations. Conclusions: Non-cycloplegic methods systematically underestimate hyperopia and therefore cannot replace cycloplegia for definitive diagnosis or spectacle prescription in pediatric populations. Cycloplegic assessment remains essential to detect amblyogenic refractive errors accurately. Non-cycloplegic methods may be integrated into large-scale screening programs for initial case detection, but positive or borderline cases must undergo cycloplegic confirmation to ensure safe and effective clinical management.