PT - JOURNAL ARTICLE AU - Xiangui He AU - Padmaja Sankaridurg AU - Thomas Naduvilath AU - Jingjing Wang AU - Shuyu Xiong AU - Rebecca Weng AU - Linlin Du AU - Jun Chen AU - Haidong Zou AU - Xun Xu TI - Normative data and percentile curves for axial length and axial length/corneal curvature in Chinese children and adolescents aged 4–18 years AID - 10.1136/bjophthalmol-2021-319431 DP - 2023 Feb 01 TA - British Journal of Ophthalmology PG - 167--175 VI - 107 IP - 2 4099 - http://bjo.bmj.com/content/107/2/167.short 4100 - http://bjo.bmj.com/content/107/2/167.full SO - Br J Ophthalmol2023 Feb 01; 107 AB - Purpose To develop age-specific and gender-specific reference percentile charts for axial length (AL) and AL/corneal radius of curvature (AL/CR) and, to use percentiles to determine probability of myopia and estimate refractive error (RE).Methods Analysis of AL, cycloplegic RE and CR of 14 127 Chinese participants aged 4–18 years from 3 studies. AL and AL/CR percentiles estimated using Lambda-Mu-Sigma method and compared for agreement using intraclass correlation (ICC). Logistic regression was used to model risk of myopia based on age, gender, AL and AL/CR percentiles. Accuracy of AL progression and RE estimated using percentiles was validated using an independent sample of 5742 eyes of children aged 7–10 years.Results Age-specific and gender-specific AL and AL/CR (3rd, 5th, 10th, 25th, 50th, 75th, 90th and 95th) percentiles are presented. Concordance between AL and AL/CR percentiles improved with age (0.13 at 4 years to >0.75 from 13 years) and a year-to-year change was observed for all except <10th percentile from 15 years. Increasing age, AL and AL/CR was associated with a more myopic RE (r2=0.45,0.70 and 0.83, respectively). The sensitivity and specificity of the model to estimate probability of myopia was 86.0% and 84.5%, respectively. Estimation of 1-year change in AL using percentiles correlated highly with actual AL (ICC=0.98). Concordance of estimated to actual RE was high (ICC=0.80) and within ±0.50D and ±1.0D of actual RE for 47.4% and 78.9% of eyes, respectively.Conclusion Age-specific and gender-specific AL and AL/CR percentiles provide reference data, aid in identifying and monitoring individuals at risk of myopia and have utility in screening for myopia. AL/CR percentiles were more accurate in estimating probability of myopia in younger children.Data are available on reasonable request. The data that support the findings of this study are available from Prof Xun Xu drxuxun@sjtu.edu.cn but restrictions apply to the availability of these data, which were used under licence for the current study, and so are not publicly available.