Frequently Asked Questions on UAB Productivity Study

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1. Why is this study so important?
It’s important because over half of America’s workforce spends their workdays in front of a computer. This is the first clinical study that documents a significant correlation between workplace productivity and computer vision problems (problems that computer users may or may not be aware of). The study results give employers hard evidence of the financial benefits of providing computer vision care for employees who use computers.

2. What were the results of the study?
While productivity is a very complex issue that incorporates a number of different factors, the study showed that people are more productive at the computer when they are given proper vision correction.

Specifically, the study drew the following conclusions:

• Uncorrected computer vision, even when there are no symptoms, can significantly affect worker productivity and accuracy.
• With a miscorrection of as little as 0.5 diopter (two “clicks” of the phoropter in a patient’s eye exam), the loss in worker productivity was 8.9%, while loss in accuracy measured 38.1%. This means that an employer with an employee that makes $60,000 a year, would reap a gain in productivity of $5,400 minus the cost to the employer of an eye exam and pair of computer glasses, which is approximately $300. This results, in the case of this $60,000-a-year employee, in a cost benefit of $18 gained for every $1 spent.
• Eye doctors cannot "guess" the correct Rx. A small miscorrection (0.5D sph equiv. or “two clicks”) can be as significant as a large miscorrection (1.0D sph equiv. or “four clicks”).
• The PRIO tester, which simulates the pixels on a computer, was used in this study to determine the most accurate Rx for computer-using patients in the study.

3. What study methods were used?
Study investigators began by doing complete vision examinations on our subjects, who ranged in age from 19 to 30 years old. Subjects completed several tasks on the computer that were calculated to assess the effects of refractive error (or visual accuracy) on their productivity. Using a PRIO vision tester, a device that simulates one’s vision at the computer and is used by many eye doctors who specialize in computer vision care, the study assessed the subjects’ computer vision using both corrected and uncorrected lenses. The lenses for each subject were then randomly assigned, without the subjects or technicians knowing which lenses were being used. This is what is meant by a double-masked, placebo-controlled, scientific protocol.

4. Why wasn’t the common eye chart to test the subjects’ vision?
The Snellen Chart, which is the eye chart with the large “E” that most patients are familiar and which was developed in the 1800’s, measures distance vision only. The PRIO tester, a much newer medical device, simulates a computer screen and measures the near power needed to work at the computer.

5. Only younger subjects were used. Would the results have been any different if the subjects were older?
No. The age of the subjects would be unlikely to change the study results.

6. What is meant by productivity?
Specifically, it refers to visual performance, which is the major component in determining productivity on a computer. The study measured the subjects’ output in terms of the time they needed to complete a task and the number of errors they made.

7. How were subjects tested?
Subjects were asked to do various tests that required them to read fonts of various sizes on the computer screen. This included identifying population listings for various counties, matching nonsense words and finding various symbols within a manuscript on the computer monitor. The subjects were timed and the number of errors calculated. They then answered a questionnaire with questions pertaining to visual problems, clarity, episodes of blurred vision, limitations, headaches, etc. Performance was compared using different lenses.

8. Would the results be different if it were done in a workplace instead of a lab?
It is unlikely.

9. It seems obvious that if a subject were not seeing the screen clearly, he or she would not be as productive.
Yes, but in cases where the correction is only slightly off, the computer user may think the he or she is seeing the screen clearly. Yet, the study found that even a slight miscorrection (0.5D) would have a significant effect on productivity over several hours. It’s analogous to the eye muscles being forced to do pushups. Over time, these pushups will impact productivity and comfort.

10. Are computer vision difficulties widespread?
Yes. In fact, studies have shown that as many as 90% suffer from Computer Vision Syndrome (CVS); The American Optometric Association has stated that 70-75% of all computer users need computer eyewear. In fact, NIOSH reports that CVS is more common than carpal tunnel syndrome and the #1 office-related complaint.

11. Why is CVS widespread?
Our eyes are not meant to spend 6 to 8 hours every day – between work and home – at computers. As a result, most computer workers – and this includes people working in many different professions – report problems.

12. What is the difference between how our eyes view the computer screen and the printed word?
Studies have long shown that the way our eyes view the computer image is very different than how they read the printed word in a book or newspaper. The images or pixels on a computer screen have poor edge definition. This can cause a repetitive focusing effort for the eye muscles, which over time generates a variety of symptoms (which is similar to any musculoskeletal injury that results from overuse).

13. What if the subjects were not seeing optimally but reported no symptoms?
It did not matter whether the subjects reported symptoms, or whether the miscorrection was small (0.5D) or large (1.0D). Productivity was significantly affected. Even individuals with no visual problems may still be losing productivity and accuracy at the computer.

14. Do you think this study will resonate with corporate America?
Absolutely. Most organizations are under pressure to maximize performance and control costs, and are therefore reluctant to add potential health costs. A workforce with reduced accuracy and overall performance due to eyestrain or headaches, especially over time, will greatly impact efficiency and productivity. This is what corporate America is facing.

Some companies, including Medtronic Corporation, AT&T, the Baby Bells, and the Social Security Administration are already aware of the benefits and offer computer vision plans to employees. Medtronic, for example, introduced a program that makes eyewear available to employees who have been diagnosed with Computer Vision Syndrome by a doctor who uses the PRIO tester. Companies don’t like to spend money, but are more than willing to make an investment that will give an immediate return. The bottom line is that workers are more productive when their vision at the computer is optimal.

15. What kinds of jobs are most affected by CVS?
Virtually any job that requires computer use can cause CVS. This can include computer programmers, editors and reporters, researchers, graphic artists, architects, insurance underwriters, air controllers, executives, lawyers, bank tellers, secretaries, etc.

16. Is there any indication that the government is taking a look at computer vision in the workplace?
Yes. Many OSHA/NIOSH studies suggest that there is a vision component in neck, back and shoulder musculoskeletal problems, and recommend that computer users have a vision exam before working at a computer. But there is no requirement for a computer exam. We hope to present the results of this study to the National Ergo Advisory Committee in the near future.

17. What evidence is there that patients need special computer glasses vs. readers?
Previous studies have shown that without having their computer vision corrected to the proper prescription, patients are more vulnerable to suffer the effects of CVS and, as this study shows, have their productivity and accuracy affected.

18. Do eye doctors offer the kinds of exams that can promise a patient that he or she has optimal computer vision?
Yes, many eye doctors who offer computer vision care, and this is a growing specialty, use the PRIO tester. This is a computer-specific exam, unlike the more traditional Snellen card used for near vision testing. And, while for this test we only used single vision lenses, many of these computer vision specialists also offer near variable focus lenses that are made especially for computer use.

19. Isn’t ergonomics the solution to CVS?
Ergonomics is important, but it will not solve computer-related vision problems. Changing one’s computer workstation may certainly help to minimize other physical symptoms. But fixing a computer vision problem can only be done with the right computer lens prescription.

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