(RxWiki News) Ordering prescription glasses online may seem like an easy way to save money. But half of all glasses order through the Internet have been found to be unsafe or have incorrect prescriptions.
About 45 percent of prescription glasses ordered online failed at least one parameter of impact testing, which ensures the safety of the wearer, or optical testing, which determines if the pair is appropriate based on a person's vision.
"If ordering prescription glasses online, check with your optometrist."
Dr. Karl Citek, a lead study author from Pacific University College of Optometry, wrote that patients who purchase eyewear without the assistance of a trained professional may not receive a product of equal performance, value or safety. They also do not receive the benefit of ensuring an accurate prescription and a proper fit.
He also noted that the online dispensing process comes with significant risks for errors in the type of lenses, the optical parameters and physical characteristics that offer sufficient protection. Though optometrists can assess the prescription of a pair of glasses from another seller, they would be unable to determine the impact resistance of finished lenses.
During the study, 10 individuals ordered two pairs of glasses, including pairs for both adults and children, from each of 10 of the most visited online optical vendors, for a total of 200 pairs of glasses. They were ordered with varying lens and frame materials, lens styles and prescriptions.
Of those ordered, 154 pairs were received. After they were received, evaluations included measurement of sphere power, cylinder power and axis, add power (if indicated), horizontal prism imbalance, and impact testing.
Several pairs were provided incorrectly such as single vision instead of bifocals, or lens treatments that were added or omitted. In 29 percent of glasses received, at least one lens was not within the parameters of the prescription. In 23 percent of glasses, at least one lens failed impact testing.
Of the lenses that failed impact testing, 38 percent of them had an added AR coating. Of the children's glasses tested, 29 percent failed impact testing.
Dr. Christopher Quinn, an optometrist with Omni Eye Associates, said consumers should be cautious when ordering any medical devices online.
"Although online retailers may effectively market cost savings associated with online purchase of eyewear, consumers should be aware, as this study point out, that the lack of oversight and quality control can lead to inferior products that could be harmful," Dr. Quinn said.
"Although consumers may view eyewear as a commodity, they should be aware that they are medical device regulated by the FDA and a valid prescription is required to obtain eyewear. Additionally important quality checks are performed on eyewear products when dispensed by licensed professionals to assure consumers of the safety and accuracy of these products."
Additional studies will be needed to assess the safety and standards of eyewear ordered online. The study was published in the September issue of Optometry.