Objective To estimate the age-and gender-specific preva-lence of posterior subcapsular(PSC),nuclear,cortical,and mixed lens opacities in a population-based sample of Latinos 40years and older.Design Population-based,cross-sectional study.Participan ts Six thousand three hundred fifty-seven Latinos 40years and older from 6census tracts in Los Angeles,Califo rnia.Methods A population-based sample of Latinos underwent a complete eye examination,including assessm ent of presence and severity of lens opacification,using the slit lamp-based Lens Opacities Classification System II(LOCS II).All lens changes(including pseudophakia /aphakia);any nuclear,PSC,and cortical opacitie s;and nuclear-only,PSC-only,and cortical-only opacities were evaluated.Frequency distributions and chi-sq uare test analyses were used to determine the age-and gender-specific prevalences for each opacity type.Main outcome measures Prevalences of cortical,nuclear,and posterior subcapsular opacities.Results Of the 7789eligible subjects,6357completed a clinical examination(82%participation rate)-.Of all participants with LOCS II grading,20%had all lens changes,7.6%had cortical-only opacities,3.5%had nuclear-only opacities,0.4%had PSC-only opacities,and 5.9%had mixed-type opacities.T he prevalence of all types of lens opacities increased wi th age(P<0.0001).Of all participants with mixed opacities,49%had monocular visual impairment and 20%had binocular im-pairment.Of all 6357participants,3.9%had undergone cataract extraction in at least one e ye.Conclusion Our data provide the first population-b ased estimates of the prevalence and severity of lens opacities in Latinos.Cor-tical opacities were the most common type.The high rate of visual impairment from lens opacities suggests that programs that increase access to cataract surgery for older Latinos could help to reduce the burd en of visual impair-ment in the United States. Objective To estimate the age-and gender-specific prevalence of posterior subcapsular (PSC), nuclear, cortical, and mixed lens opacities in a population-based sample of Latinos 40 years and older. Design Population-based, cross-sectional study. Participan ts Six thousand three hundred fifty-seven Latinos 40 years and older from 6 census tracts in Los Angeles, Califo rnia. Methods A population-based sample of Latinos underwent a complete eye examination, including assessor ent presence and severity of lens opacification, using the slit lamp-based Lens Opacities Classification System II (LOCS II). All lens changes (including pseudophakia / aphakia); any nuclear, PSC, and cortical opacitides; and nuclear-only, PSC- only, and cortical-only opacities were evaluated as . Frequency distributions and chi-sq uare test analyzes were used to determine the age-and gender-specific prevalences for each opacity type. Main outcome measures Prevalences of cortical, nuclear, and posterior subcapsular opacities. Results of the 7789eli Of all participants with LOCS II grading, 20% had all lens changes, 7.6% had cortical-only opacities, 3.5% had nuclear-only opacities, 0.4% had PSC -only opacities, and 5.9% had mixed-type opacities. The prevalence of all types of lens opacities increased wi th age (P <0.0001). All participants with mixed opacities, 49% had monocular visual impairment and 20% had binocular im-pairment. Of all 6357 participants, 3.9% had undergone cataract extraction in at least one e ye.Conclusion Our data provide the first population-b ased estimates of the prevalence and severity of lens opacities in Latinos. Corotical opacities were the most common type. high rate of visual impairment from lens opacities suggests that programs that increase access to cataract surgery for older Latinos could help to reduce the burd en of visual impair ment in the United States.