Warby Parker, the $US1 billion+ eyeglasses retailer, just launched an app that could make it easier to check your eyeglass prescription.

The app, called Prescription Check, is meant to help people check out their prescription using just a phone and a computer, no eye doctor’s office visit necessary.

If you’ve ever been to the eye doctor, you are most likely familiar with the big metal fixture patients peer through while answering questions about the letters on the chart.

It’s not the first time that companies have tried to take a telemedicine approach to eye exams. And from the Fall 2016 to Winter 2017, Warby Parker piloted a telemedicine device at a few of its New York City locations, including Grand Central Station. That pilot program has since ended.

Ultimately, Warby Parker said that it decided to build its own test after vetting existing programs, and deciding that the user experience didn’t meet its standards.

Here’s how Warby Parker’s app works:

1. First you have to meet the eligibility requirements (Warby Parker customer, in a handful of states, within a certain age, no history of eye disease or diabetes, among others).
2. The technology then runs you through three tests: a Fan Chart test, a Duochrome test, and a Landolt C test. To perform the tests, you need to have your glasses on, and use your computer monitor and phone.
3. Once that’s all done, the information gets sent to a doctor.
4. In about 24 hours, you get your results sent via email. If it hasn’t changed, the doctor will write you a new one. If it has, the doctor might recommend a visit to the optometrist.

It’s a key move for Warby Parker, which has a big presence as an online eyeglass retailer. If people can get their eyes checked from home, it could open up the opportunity to shop for glasses online to more people.

What the app can and can’t tell you about your eyes

By using a phone and computer, you’re not necessarily getting a full workup as you would at an eye doctor’s office, such as getting your eyes dilated (which can detect eye problems). The test is only checking your refractive error, not overall eye health.

On its prescription app site, Warby Parker provides a disclaimer that spells it out:

“Prescription Check is not a comprehensive eye health exam and it isn’t meant to replace visits to your eye doctor. It’s important to also get your eye health examined even if you aren’t experiencing any vision problems, so please follow the advice of your doctor. Good to keep those peepers in check :-)”

The approach of just checking refractive error worries some eye doctors, who are concerned telemedicine approaches — where a doctor isn’t necessarily in the room — could be bad for patients. The American Optometric Association cited the lack of eye health testing as its main concern with telemedicine approaches like Warby Parker’s.

“When patients rely on an app for an eyeglass or contact lens prescription, they can receive inaccurate or misleading information and potentially delay essential sight saving treatment. An online eye test does not completely cover any one of the 12 components of a regular in-person, comprehensive eye exam,” the AOA said in a statement to Business Insider. “Touting virtual technologies that are not proven and subvert care sets us all back.”

A spokeswoman for Warby Parker said that the tests that are part of the app are based on existing vision tests. So far, the test hasn’t gone through external clinical testing, nor have the results of the test’s accuracy been published, but the company said it is “beginning to work with external parties to complete third party validation studies.” Warby Parker also said it has registered the app with the FDA. “We are fully confident that our test is safe and accurate,” the company said in an email to Business Insider.

For now, the test is only available to people who qualify in New York, California, Virginia, and Florida who have Warby Parker glasses. Warby Parker plans to open up the app beyond existing customers starting in the summer, and plans to expand beyond those four states around the same time.

Here’s the full statement from AOA (emphasis added):

With blindness being the biggest fear in America, the American Optometric Association (AOA) tenaciously upholds the highest standards when it comes to patient eye health and vision care. Through the delivery of personalised health care, doctors of optometry assure precise and healthy vision, identify and treat glaucoma and serious infections and ensure early diagnosis of immediate threats to overall health, including hypertension, stroke and diabetes, which may have no obvious signs or symptoms. This is precisely what makes these clinically unproven tests, like Prescription Check and Opternative, so dangerous — they give patients a false sense of security. In recent years, instead of using technology as doctors do to save lives and achieve improved outcomes, some have used it as a smokescreen to try to mislead the public and undermine very basic quality care standards. The AOA and our state affiliates are proud of our success in alerting the public, the news media, elected officials and regulators to false product claims and taking action to safeguard public health.

When patients rely on an app for an eyeglass or contact lens prescription, they can receive inaccurate or misleading information and potentially delay essential sight saving treatment. An online eye test does not completely cover any one of the 12 components of a regular in-person, comprehensive eye exam. National agencies, including the National Eye Institute and the Centres for Disease Control and Prevention, agree that a comprehensive eye examination is the only way to know whether your eyes and vision are healthy. And last year, the National Academies of Science, Engineering and Medicine issued a national call to action to make eye health a priority. Touting virtual technologies that are not proven and subvert care sets us all back.

Americans have voiced their concerns loud and clear. Other online vision apps have been put to the test and ultimately failed to gain consumer trust. According to one survey, 92 per cent of participants would prefer getting a comprehensive eye exam.

Doctors of optometry use advanced, proven technology every day. They can see more and detect more and help patients because of them. The progressive answer to eye and vision health care is not to focus on being the next big consumer brand or app. Instead, innovators need to focus on delivering tools that help advance patient care, because “virtual” care is no substitute for actual health care. The public should know that there’s less here than meets the eye. In fact, it would have been hard to predict that any company could offer less than the already discredited online sight apps, but that appears to be the case here.

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