Research on the predictive performance of using ROC curve to evaluate axial length for myopia in children and adolescents

BACKGROUND: Assessing myopia risk can help clinicians intervene as early as possible. There is still a lack of reference values for predicting myopia based on the axial length (AL) of children. The study aims to explore the relationship between AL and myopia, and to predict the risk thresholds of AL in children of different age and sex groups. METHOD: Visual acuity examination, refractive screening and ocular axis examination of 2388 children aged 7-18 (4776 eyes) from 8 schools in a certain area of Beijing were used as the data source, we evaluated the predictive ability of AL for myopia in children using Receiver Operating Characteristic (ROC) curves, and constructed Logistic Regression to analyze the reference value of AL threshold for children of different age and sex groups. RESULTS: The myopia rate among children and adolescents was 51.47%. The AL and SE were significantly correlated by Spearman correlation coefficient(P < 0.01). Predicting myopia in children based on their AL has a good reference value(AUC = 0.73). Children with AL ≥ 23.92 mm have a significantly higher myopia rate than those with AL < 23.92 mm (χ²=661.14, P < 0.01). The difference in AL among children of different age groups is statistically significant, and the AL shows an increasing trend with age. Among them, the AL threshold for children aged 7-12 is 23.67 mm, while that for children aged 13-15 is 23.92 mm, and children aged 16-18 is 24.42 mm. Children with an AL ≥ the threshold have a 4.41-fold higher risk of myopia than those with an AL < the threshold (OR = 4.41, 95% CI = 3.88-5.01). There is a statistically significant difference in AL between children of different sex groups. The male group has a higher AL(24.27 mm) than the females (23.71 mm), and children with AL ≥ threshold have a 5.58-fold higher risk of myopia than those with AL < threshold (OR = 5.58, 95% CI = 4.93-6.33). CONCLUSION: The correlation between SE and AL was strong in school children. Age-specific and sex-specific AL threshold for myopia might provide reference data as a useful indicator, aid in identifying and monitoring individuals at risk of myopia and have utility in population-based screening for myopia in children and adolescents.