Parents often arbitrarily assume that their child is “nearsighted” when they notice abnormal vision. This may be because the incidence of myopia in children is relatively high, but abnormal vision and myopia cannot be equated. The main function of the eye is to “see”, and external objects are imaged on the retina through the refractive system of the eye, and any factor that affects clear imaging can cause abnormal vision. To use an extreme analogy, a 70-year-old man’s vision has declined, most likely not because of “myopia” but because of senile cataracts. If a child’s vision is abnormal and the relevant tests exclude organic eye pathology, the doctor’s diagnosis is usually refractive error. Refractive errors include myopia, hyperopia, astigmatism, and presbyopia. It is necessary to have an optometric examination to find out which is the case. School-age children, who used to have normal vision and have had recent vision loss, are generally more likely to be nearsighted. Preschool-age children, on the other hand, who are found to have poor vision when they first start their vision screening, are likely to be farsighted or astigmatic. This is the general rule of thumb in general. Exactly what the case is will require dilated eye examinations to make a clear diagnosis.