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Treatment is effective for many eye problems, but screening people who do not have eye symptoms doesn’t improve benefits

Chou R, Dana T, Bougatsos C, et al. Screening for Impaired Visual Acuity in Older Adults: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force. JAMA. 2016;315:915-33.

Review questions

In older people with no eye symptoms or complaints, what are the benefits and harms of vision screening? What are the benefits and harms of treating early vision impairment?


Reduced clarity or sharpness of vision can decrease functioning and quality of life and increase risk of falls and other accidents. Although impaired vision is more common in older people, it may occur slowly and is not always identified or treated. Screening people who do not have eye complaints may or may not be of benefit.

How the review was done

The researchers did a systematic review based on studies available up to February 2015.

Key features of the trials were:

  • people were 65 years of age and older;
  • people in screening studies had no known vision impairment (they could wear glasses or contact lenses) and did not seek vision assessments; and
  • people in treatment studies had mild or moderate vision impairment (better than 20/200 but worse than 20/40).

What the researchers found


  • Universal screening (screening everybody) identified more people with impaired vision than targeted screening (screening people who meet certain criteria), but it did not lead to improved vision.
  • Screening did not improve vision compared with no screening. In part, this may be because screening tools (AMSTAR grid, questionnaires, flip charts, computerized screening) are not very accurate.

Treatment of vision impairment

  • Treatment is effective for many eye problems (see Table).


Treatment is effective for several types of vision complaints in older people with no eye symptoms, but there is not enough evidence to assess the balance of benefits and harms of screening.

Screening or treatment for vision impairment in people 65 years of age and older*





No known vision impairment (with or without corrective lenses)

1 study of 3346 people found that universal screening identified impaired vision in 27% of people compared with 3% in targeted screening; however, groups did not differ for vision after 5 years.

3 studies of 4728 people found that screening did not differ from no screening, usual care, or delayed screening for vision or other clinical outcomes at up to 5 years.

No studies assessed or reported harms of screening.


Refractive error (near-sightedness, far-sightedness, astigmatism)

2 studies found that corrective lenses improved vision-related quality of life but not functional outcomes.

1 study of 156 people found that multifocal lenses were associated with increased risk of falls compared with unifocal lenses.



1 study found that immediate cataract surgery for the first eye reduced risk of second falls compared with delayed surgery.


Dry age-related macular degeneration

1 study of 2556 people found that antioxidant supplements reduced vision loss after 10 years.

1 study of 3476 people found that zinc reduced risk of death.

1 study of 300 people found that fish oil capsules reduced risk of developing cataracts, worsening cataracts, or need for cataract surgery but not vision loss.


Wet age-related macular degeneration

4 studies found that vascular endothelial growth-factor inhibitors increased likelihood of improved vision compared with sham injections.

1 study found that ranibizumab did not reduce death after 2 years.


Age-related macular degeneration (wet or dry)

1 study found that zinc was associated with hospitalization for genitourinary problems, and antioxidants were associated with increased risk of yellow skin.

Antioxidant vitamins and minerals were not linked to adverse events.

1 study found that supplements did not differ from placebo for adverse events, serious adverse events, or serious adverse events involving the eye.

*There is not enough evidence to assess the balance of benefits and harms of screening.


A harmless, inactive, and simulated treatment.
Systematic review
A comprehensive evaluation of the available research evidence on a particular topic.
The body's network of blood vessels. It includes the arteries, veins, and capillaries that carry blood to and from the heart.

Related Web Resources

  • Eye examinations for adults

    Health Link B.C.
    Refer to these guidelines for how often you should have an eye exam. For example, at age 50 consider yearly examinations for glaucoma or other vision problems. If you have a disease that affects your eyes, have an exam every year.
  • Cataract surgery

    Mayo Clinic
    A cataract causes blurry vision. Cataract surgery removes the cloudy lens from your eye and replaces it with an artificial one. Cataract surgery usually takes an hour or less to complete, and you go home the same day.
  • Blepharitis

    Mayo Clinic
    Blepharitis is an eye condition that results in swelling of your eyelids. Symptoms include watery, itchy, red eyes. Wash eyelids with a warm washcloth and diluted baby shampoo to reduce symptoms. Some medications may also help.
DISCLAIMER These summaries are provided for informational purposes only. They are not a substitute for advice from your own health care professional. The summaries may be reproduced for not-for-profit educational purposes only. Any other uses must be approved by the McMaster Optimal Aging Portal (

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