[On mass examination with a mobile vision-screening unit].
D000293:Adolescent; D001251:Astigmatism / Q000175:diagnosis; D002648:Child; D005260:Female; D006801:Humans; D006956:Hyperopia / Q000175:diagnosis; D008297:Male; D008403:Mass Screening; D009216:Myopia / Q000175:diagnosis; D012029:Refraction, Ocular; D012030:Refractive Errors / Q000175:diagnosis*; D014787:Vision Tests / Q000295:instrumentation; D014792:Visual Acuity