Optimising non-cycloplegic screening strategies for early detection of pre-myopia and myopia in young children

Purpose: Early detection of myopia is essential to delay its onset and progression. Pre-myopia, defined by an inadequate hyperopic reserve, increases myopia risk in childhood. However, effective screening methods remain limited. This study aimed to develop practical non-cycloplegic screening methods for pre-myopia and myopia in 6- to 7-year-olds to support earlier interventions. Methods: This cross-sectional study of 621 Irish schoolchildren (mean age: 7.12 ± 0.45 years; 51.8% boys) assessed uncorrected distance visual acuity (UDVA). Cycloplegic spherical equivalent refraction (SER) classified refractive status (myopia: SER ≤ −0.50D; pre-myopia: SER > −0.50 ≤ 0.75D). Pre- and post-cycloplegic SER were measured using the Welch Allyn Spot Vision Screener and Dong-Yang Rekto-ORK 11, respectively. Axial length (AL) and corneal radius (CR) were measured with the Zeiss IOLMaster and parental myopia history via questionnaire. Logistic regression and ROC curves evaluated non-cycloplegic screening methods. Results: Pre-myopia prevalence was 24.3% (95% confidence intervals (CI): 29.3–36.2), and myopia prevalence was 3.3% (CI: 2.5–5.5). UDVA screening had an area under the curve (AUC) (CI) = 0.72 (0.59–0.86) and 0.42 (0.36–0.47) for detecting myopia and pre-myopia, respectively. For pre-myopia discrimination, non-cycloplegic SER, AL, AL/CR and parental myopia had AUCs of 0.67 (0.62–0.72), 0.67 (0.62–0.72), 0.69 (0.64–0.74) and 0.59 (0.53–0.64), respectively. The best method combined non-cycloplegic SER and AL/CR (AUC = 0.72 (0.67–0.76)). Including UDVA or parental myopia did not improve results. For myopia detection, AUCs were non-cycloplegic SER:0.84 (0.72–0.97), AL:0.88 (0.82–0.95), AL/CR:0.84 (0.75–0.94) and parental myopia:0.62 (0.48–0.75). The best method combined AL and non-cycloplegic SER 0.94 (0.90–0.99). Adding parental myopia did not improve the AUC = 0.93 (0.87–0.99) but adding UDVA achieved an AUC = 0.95 (0.90–0.99). Conclusion: While UDVA alone provided acceptable discrimination for myopia, it was insufficient for screening pre-myopia. Non-cycloplegic SER alone had relatively poor discrimination for pre-myopia, but its performance improved when combined with the AL/CR ratio. The best results for myopia discrimination were achieved by combining non-cycloplegic SER, axial length and UDVA measures.