October 16, 1997 For Immediate Release Andover Communications, Inc. Steve Clark 201-947-4133

For Information Contact Jon Torrey 503-636-3707

Computer-Specific Vision Testing May Provide Solution to Eyestrain Symptoms

(Portland, OREGON) By the year 2000, nearly 75% of all U.S. workers will be in front of a computer screen several hours a day, according to a recent report in the Journal of Behavioral Optometry. This report is one in a series of studies pointing to computer eyestrain as an office ergonomic epidemic which will worsen by the end of the decade. "Because computing is permeating our society so rapidly, computer eyestrain is among the most challenging issues facing office ergonomics," said Jon Torrey, vice president of marketing at PRIO® Corporation. "Potentially it's as debilitating to office workers, and as costly to companies, as carpel-tunnel syndrome and other repetitive stress injuries."

Earlier studies tout a similar view. A 1991 Harris poll cited computer-related eyestrain as the number one office-related health complaint in the United States. In 1992, MacWorld reported that nearly half of all office workers complained of eyestrain. Just one year earlier, a study by the National Institute of Occupational Safety and Health (NIOSH), indicated that 88% of the 66 million people who work at computers for more than three hours a day—nearly 60 million—suffer from symptoms of eyestrain. These and many other studies point to symptoms, resulting from the use of computers, as an office epidemic of increasing severity.

Today's new, easy-to-use graphical interfaces, on-line services and the Internet's World Wide Web, linked with an increasingly competitive business environment, are drawing millions to personal and business computing—and many of them are spending more time in front of computer screens. As computers become an increasing part of our work and personal lives, so do their potential health hazards, including eyestrain. Still, this health concern goes largely unaddressed by ergonomic engineering.

Addressing Computer Eyestrain Via Ergonomics has Fallen Short
For years, ergonomics and human factors designers have worked to adapt human anatomy to computers to increase computing comfort, and to reduce the economic impact of workplace injuries and the liabilities on companies that rely on computers. The resulting ergonomic keyboards and mice, tilting computer screens, wrist supports and other devices relieve the physical stress on some parts of the human anatomy. Human factors engineers have not, however, successfully addressed computer eyestrain. Most frequently the result of their ergonomic efforts emphasize controlling the computing environment—regulating ambient lighting, maintaining a working distance for 18-24 inches, reducing computer screen reflections, and filtering computer screens. While helpful, these efforts only partially address computer eyestrain.

According to Mr. Torrey, "Although fifteen years of vision research have consistently shown that viewing a computer screen is not physiologically the same as reading the printed page, such findings are rarely applied to human factors engineering. Instead ergonomics engineers, like the public at large, assume, incorrectly, that reading a computer display is like reading ink on paper. Nothing could be farther from the truth."

Computer Eyestrain is Actually a Form of Repetitive Stress
After sitting at a computer several hours per day, computer users often complain of the vague, yet nagging, symptoms of visual discomfort. Headaches, burning or tired eyes, blurred vision, loss of focus, double vision, and neck and shoulder pain are among the typical symptoms.

Most computer-related eyestrain symptoms stem from viewing pixels, rather than print. Computer pixels are brighter at their center and grow dimmer toward their edges. Because they lack the sharp edges of print, pixels don't provide the information the human eyes require to "lock in" the focus. So computer users' eyes tend to drift toward a natural point of focus, as if the viewer were staring off into space. Usually this puts the focal point somewhere behind the computer screen.

But the brain constantly tries to readjust the focus to the plane of the screen. So hour after hour, the eyes' focusing muscles are flexed over and over in an attempt to keep the focus on the screen, only to drift back toward a resting point. "This repetitive re-focusing is very similar to other repetitive stress injuries where there's an unnatural fit between the body and the machine," said Mr. Torrey. "At PRIO, we have applied this understanding of repetitive and constant refocusing, to develop a vision tester that allows eyecare specialists to prescribe eyeglasses that can eliminate visual stress for computer users. It works by placing their resting focus naturally at the plane of the screen rather than behind it, and thereby eliminates the constant, repetitive refocusing."

New Study Shows Prescription Glasses Reduce or Eliminate Computer's Repetitive Stress on the Eyes
A recent experimental study evaluates the effectiveness of computer-specific eyeglasses in alleviating the symptoms of eyestrain. ("Reducing Visual Stress Symptoms of VDT Users With Prescription Eyeglasses," published in the proceedings of the Computer Human Interface [CHI] Society 1995 Mosaic of Creativity, Erik Nilsen, PhD, et al, Lewis & Clark College, Portland, Ore.). The study evaluates a method of prescribing computer specific glasses to reduce computer eyestrain and improve vision.

Thirty-seven participants including 24 men and 13 women in three age categories (20-30 years; 35-45 years; and 50-65 years old) completed the double-blind study. None of the participants knew whether they were using placebo eyeglasses or a PRIO prescription for combating computer eyestrain. The results of Nilsen's experiments indicate that users with computer-related eyestrain symptoms were more likely to be farsighted, work more hours per day, and to have more years of computer experience. It also noted that 70% of the experiment's participants across all three age groups preferred eyeglasses with computer-specific prescriptions generated using the PRIO Vision Tester, because this eyewear reduced or eliminated their symptoms of eyestrain.

Combine Ergonomics with Optometrics To Address Computer Eyestrain
By understanding the relation of optometrics to ergonomic design, ergonomics engineers can better understand the physiological origin of computer eyestrain. They should begin by reviewing vision related research, which repeatedly shows that the traditional means of controlling the computer user's environment only partially addresses the issue of computer eyestrain.

A recent optometric study might facilitate a better understanding of this issue amongst ergonomicists. This study identified what differentiates computer users with eyestrain from those who don't. It involved 22 optometrists around the country who collected data on 324 patients.

To help optometrists better understand computer eyestrain patients, and to help them identify patients who might be exhibiting computer-related eyestrain, PRIO Corporation recently conducted a demographic study on VDT users. (Published in the Journal of the American Optometric Association, August 1995.) The study examined computer eyestrain in VDT users based on their gender, age, VDT work distance, number of years working at a VDT, number of hours per day working at a VDT, VDT screen colors, and VDT-related symptoms. The findings included:

• Males and females are roughly equivalent in reporting VDT symptoms.
• There appear to be no statistical differences between those reporting symptoms and those not reporting symptoms, based upon age or VDT working distance.
• There were no statistical differences among those participants using color, green, or black and white screens.
• Average VDT work experience was 5 years.
• The mean VDT usage per day was 4.8 hours.

About PRIO
Available since October, 1992, the PRIO VDT vision tester gives doctors an effective, proven way to address computer eyestrain. The PRIO VDT vision tester is a patented, FDA market-approved Class 1 Medical Device. It is stocked and available through the twenty-one optical laboratories in the PRIO network of authorized distributors. Located in Beaverton, OR., PRIO was founded in 1986.

For more information on PRIO Corporation and the PRIO Provider Network of eye doctors, call or visit the company's website at www.prio.com.

PRIO® is a registered trademark of PRIO Corporation.