A group of researchers led by Prof. Karla Zadnik, chair at the College of Optometry at The Ohio State University in Columbus, conducted an extensive study during which more than 4,500 children, aged 6-11 years old, were observed.
Their aim was to see if it was possible to come up with a formula that predicts nearsightedness. Issued in JAMA Ophthalmology’s latest number, they identified 414 children who became nearsighted in the next years following their participation in, usually during their 7 and 13 years of age.
Nearsightedness, also known as myopia, expresses as a blurry vision for more distant images. At the beginning of the research, all children had regular vision, and they were tested against various risk factors for nearsightedness during a 20-year follow-up period.
The number one risk factor that hinted toward future myopia is called refractive error, only one of the 13 causes that can lead to developing the condition. Refractive errors prevent good vision due to faulty focus of the eye; it also refers to the eyeglasses prescription that a doctor establishes following an eye test.
The optometrist performs an easy test by asking the patient which lens helps them see better while reading off an eye chart. The researchers found out that normal vision during early childhood can develop symptoms of farsightedness as they approach the age of 6-7 years old.
The test revealed that myopia was easily anticipated, and it could foresee if the child will be experiencing little or none farsightedness. Researchers tested several health risk factors, such as watching television too closely, reading in poor light and doing unprotected computer work, but they did not find conclusive proof in connection with developing nearsightedness.
According to Prof. Zadnik, these activities have been counted as risk factors for a long time now, and research in this matter is rather difficult to refute. Still, this extensive study they conducted, containing the most ethnically representative participant, showed no considerable link.
The prediction model was found to be true across ethnicities, even though slight differences could be noticed. However, one rule applied to them all: the main cause for nearsightedness is the fact that the eyeball grows longer than what usually offers good vision, messing with the image perception.
Same study discovered during the follow-up years that spending more time outdoors, during childhood, is linked with a lesser chance of developing nearsightedness. Prof. Zadnik stated that even though the association was found to be true, the scientists could not find out why, so they omitted it from the list of reliable predictors for nearsightedness.
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