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Myopia Growth Chart Based on a Population-Based Survey (KNHANES IV-V): A Novel Prediction Model of Myopic Progression in Childhood.

PURPOSE
To introduce a novel myopia growth chart based on a population-based survey for the prediction of myopic progression.


METHODS
The study included 7,695 Korean participants aged 5 to 20 years from a population-based health survey (Korean National Health and Nutrition Examination Survey IV-V). The authors collected spherical equivalent (SE) data converted from noncycloplegic refraction data. To create a myopia growth chart, data were arranged in the order of SE from hyperopia to myopia to acquire specific percentiles of the SE by age. Myopia progression rates were calculated between two specific ages in each percentile.


RESULTS
The mean age of the participants was 11.8 years and the mean SE was -1.82 diopters (D). The SE of the 10th percentile was +0.72 D for participants aged 5 and -0.25 D for those aged 20 years, resulting in a total change in refraction of -0.97 D. In contrast, the SE of the 90th percentile was -0.75 D for participants aged 5 years and -6.73 D for those aged 20 years, showing myopia progression of -5.98 D. The myopia progression rate from 5 to 20 years of age was estimated as -0.06, -0.15, and -0.40 D/year in the 10th, 50th, and 90th percentile groups, respectively.


CONCLUSIONS
The myopia growth chart may be used to diagnose the severity or to estimate the progression of myopia. A patient in a higher percentile of myopia for his or her age may have myopia progressing at a faster rate and thus require close observation. [J Pediatr Ophthalmol Strabismus. 2019;56(2):73-77.].