Question

now a days childerns are effected by poor side at early age collect information

Answer 1

Refractive errors are the most common cause of vision problems among school-age children. 
Learning disabilities (LD) are another concern with school-age children. Learning disabilities are psychological disorders that affect learning.
Streff syndrome, or non-malingering syndrome, is a rare visual condition that causes both distance and near vision to deteriorate temporarily. Most common among children ages 10 to 14, this condition also decreases the eye's ability to focus (accommodate), often causing struggles with schoolwork.
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