Peek, the smartphone eye test app designed to improve eyecare in remote areas, has been found to be as accurate as traditional methods. According to a study published last week, tests with the app carried out between December 2013 and March 2014 produced levels of accuracy that were on a par with paper-based charts and expensive illuminated vision boxes found in clinics.
The Portable Eye Examination Kit (Peek) consists of a series of apps and an add-on called PeekRetina. The study focused on one specific app called Peek Acuity, which measures how clear the patient’s eyesight is. 233 people were tested in their own homes and later re-tested in clinics in Kenya. The average difference was equal to less than one line on an eye chart.
The tests used Peek Acuity at a distance of 2 m and 3 m (6.6 ft and 9.8 ft) with a tumbling E Snelllen chart, where the letter appears on the screen in one of four orientations. The patient indicates the perceived direction and the tester uses the touchscreen to swipe accordingly, so entering the information into the system.
The app vision test is designed not to be dependent on familiarity with symbols or letters used in the English language. The eye tests were carried out at the participant’s home and in a clinic on two consecutive days. The traditional Snellen test took 82 seconds, while the Peek Acuity test proved a little quicker at 77 seconds.
The researchers are carrying out other studies to determine the suitability of the system in different contexts and with different machines and operating systems. Though participants of the current study were all aged 55 or over, one of the new studies will include a trial with over 20,000 schoolchildren.
The inspiration for the project arose from the difficulties to transport bulky eye equipment to remote areas in Kenya.
"With most of the world’s blind people living in low-income countries, it is vital we develop new tools to increase early detection and appropriate referral for treatment," says lead author Dr Andrew Bastawrous, lecturer in International Eye Health at the London School of Hygiene & Tropical Medicine and co-founder of Peek. "Mobile phone use is now so widespread that it seemed to be an ideal platform."
Peek was designed and developed by the London School of Hygiene & Tropical Medicine in conjunction with the University of Strathclyde and the NHS Glasgow Centre for Ophthalmic Research.
The results of the study were published in the journal JAMA Ophthalmology.
The video below shows how Peek can be applied in the real world.