title: The geographic factor in the onset of presbyopia.
mesh_terms: D000065:Accommodation, Ocular; D000328:Adult; D000367:Age Factors; D000368:Aged; D000531:Altitude; D005060:Europe; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011305:Presbyopia / Q000453:epidemiology / Q000209:etiology*; D011647:Puerto Rico; D012030:Refractive Errors / Q000453:epidemiology; D011795:Surveys and Questionnaires; D013696:Temperature; D014329:Tropical Climate; D014466:Ultraviolet Rays / Q000009:adverse effects*; D014481:United States