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Purpose To estimate the prevalence of refractive errors in adult Chinese Americans, and evaluate factors associated with myopia and high myopia. Design A population-based, cross-sectional study. Methods Chinese Americans 50 years and older residing in Monterey Park, California, were recruited. Noncycloplegic automated refraction with supplemental subjective refraction was performed. Myopia, high myopia, hyperopia, and high hyperopia were defined as a spherical equivalent of < −0.5 diopter (D), < −5.0D, > +0.5D, and ≥ +3.0D, respectively. Astigmatism and high astigmatism were defined as a cylinder of > 0.5D and > 2.25D, respectively. Risk factor assessment was guided by a conceptual model. Results Data from 4144 participants were analyzed. The overall prevalence of myopia, high myopia, hyperopia, high hyperopia, astigmatism, and high astigmatism was 35.1% (95% confidence interval, 33.6%–36.6%), 7.4% (6.6%–8.3%), 40.2% (38.7%–41.8%), 2.7% (2.2%–3.3%), 45.6% (44.1%–47.2%), and 3.7% (3.1%–4.3%), respectively. The prevalence of myopia and high myopia was lower among older individuals (Ps < 0.05). Reversed age trends were observed for the other refractive errors (Ps < 0.05). There was no sex difference in the prevalence of refractive errors, except for a higher prevalence of hyperopia among females (P = 0.010). Age, acculturation, education, income, marital status, birth country, history of ocular disease, non-ocular comorbidities, and recent eye exam were associated with prevalence of myopia. All of these factors, except for acculturation, were also associated with high myopia. Conclusions Our data present the first population-based estimates of the prevalence of refractive errors among adult Chinese Americans. Compared with whites, Hispanics, and blacks, Chinese Americans have a higher burden of myopia, high myopia, and astigmatism.

; for the Chinese American Eye Study Group IMPORTANCE Visual impairment (VI) and blindness continue to be major public health problems worldwide. Despite previously published studies on VI in Chinese and other racial/ethnic populations, there are no data specific to Chinese American adults. OBJECTIVES To determine the age-and sex-specific prevalence and causes of VI and blindness in adult Chinese Americans and to compare the prevalence to other racial/ethnic groups. DESIGN, SETTING, AND PARTICIPANTS In this population-based, cross-sectional study of 10 US Census tracts in the city of Monterey Park, California, 4582 Chinese American adults 50 years and older underwent complete ophthalmologic examinations, including measurement of presenting and best-corrected visual acuity (BCVA) for distance using the Early Treatment Diabetic Retinopathy Study protocol from February 1, 2010, through October 31, 2013. MAIN OUTCOMES AND MEASURES Age-specific prevalence and causes of VI and blindness for presenting and BCVA. RESULTS Of the 5782 eligible adults, 4582 (79.2%) completed an in-clinic eye examination. Of the 4582 participants, most were born in China (3149 [68.7%]), female (2901 [63.3%]), and married (3458 [75.5%]). The mean (SD) age was 61 (9) years. The prevalence of presenting VI was 3.0% (95% CI, 2.5%-3.5%), with 60.0% of this prevalence being attributed to uncorrected refractive error. The overall age-adjusted prevalence for VI (BCVA of Յ20/40 in the better eye) was 1.2% (95% CI, 0.9%-1.5%). The overall age-adjusted prevalence of blindness (BCVA of Յ20/200 in the better-seeing eye) was 0.07% (95% CI, 0%-0.2%). The prevalence of VI and blindness was higher in older Chinese Americans compared with younger. The primary causes of VI were cataracts and myopic retinopathy; the primary cause of blindness was myopic retinopathy. CONCLUSIONS AND RELEVANCE The prevalence of VI in Chinese Americans is similar to that of non-Hispanic white and Latino individuals in the United States and similar to or lower than the prevalence previously reported for Chinese adults from non-US studies. The prevalence of blindness is lower than that noted in other US or non-US studies. Myopic retinopathy is a frequent cause of VI and blindness in Chinese Americans that has not been commonly observed in other racial/ethnic groups. Because myopia frequently develops at a young age, Chinese Americans should be educated regarding the importance of regular screening of preschool and school-aged children to reduce the development and progression of myopia.