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    Attention COACH STUDY participants:

    The principal investigators of the study request that you use the official version of the modified score here.

    Color Vision Screening (Ishihara Test)

    Assess for red-green color blindness.

    INSTRUCTIONS

    • Ensure proper room lighting and phone brightness.

    • Wear any glasses necessary for near vision.

    • Hold screen at a comfortable reading distance (~30 inches or 75 cm).

    • Test each eye independently.

    When to Use
    Pearls/Pitfalls
    Why Use

    • To screen for red-green color blindness.

    • This test can also provide an initial assessment regarding the type of red-green color blindness (protan or deutan).

    • This test evaluates for the most common type of color blindness (red-green deficiency) and not other types of color blindness.

    • For purposes of rapid screening, this test uses an abbreviated version of the concise 14 plate test. The complete test consists of 38 Ishihara pseudoisochromatic plates, and a shorter 24 plate version exists as well.

    • This abbreviated version of the 14 plate test excludes the hidden digit plate (original plate 9) and the line tracing plates (original plates 11 and 14).

    • Testing is less accurate in patients who have near visual acuity less than ~20/100 at 30 inches.

    • This test is less reliable in very young children (<5 years of age).

    • Ishihara pseudoisochromatic plates are the most commonly used initial test for color vision testing; however, there are other tests which may be more accurate and sensitive, but more time-consuming (e.g. Farnsworth Panel D-15 and Farnsworth-Munsell 100-hue tests).

    • An alternative pseudoisochromatic plate test is the Hardy-Rand-Ritter (HRR) test.  

    Provides a rapid assessment of color vision and evaluation of red-green color blindness.

    12
    Other number
    Plate cannot be read
    8
    3
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    Plate cannot be read
    5
    2
    Other number
    Plate cannot be read
    29
    70
    Other number
    Plate cannot be read
    74
    21
    Other number
    Plate cannot be read
    7
    Other number
    Plate cannot be read
    45
    Other number
    Plate cannot be read
    2
    Other number
    Plate cannot be read
    16
    Other number
    Plate cannot be read
    3
    5
    35
    Other number
    Plate cannot be read
    6
    9
    96
    Other number
    Plate cannot be read

    Result:

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    Next Steps
    Evidence
    Creator Insights
    Dr. Shinobu Ishihara

    About the Creator

    Shinobu Ishihara, MD, (d. 1963) was an army opthamologist in Tokyo, Japan. He was also the chairman of the ophthalmology department at the Imperial University of Tokyo. Dr. Ishihara’s research interests included isochromatic vision and myopia.

    To view Dr. Shinobu Ishihara's publications, visit PubMed

    Content Contributors
    About the Creator
    Dr. Shinobu Ishihara
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