Visual screening of school children.
D000293:Adolescent; D002648:Child; D005387:Finland; D006801:Humans; D006956:Hyperopia / Q000453:epidemiology; D008403:Mass Screening; D012029:Refraction, Ocular; D013285:Strabismus / Q000453:epidemiology; D014786:Vision Disorders / Q000453:epidemiology*; D014787:Vision Tests; D014792:Visual Acuity