Color Blind Test
CBT
Description
"Color Blind" test evaluates your ability to distinguish colors, often using pattern-based images like the Ishihara test. It’s used to diagnose inherited color vision deficiencies—typically red-green—or detect changes caused by medications, eye disease, or nerve damage. This screening is also required in careers where color perception is critical. Results help identify limitations, recommend support tools, or confirm the need for job accommodations. Ongoing testing is helpful for tracking color sensitivity and maintaining long-term vision awareness and safety.
Test Category
Eye Function
Procedure
Non-Invasive
Sample Type
No biological sample is needed for this test.
Units
Points
Procedure Category
Assess
Test Group
Ophthalmological System Group
Test Group Description
Ophthalmological System Group: Tests within this group focus on evaluating the health and function of the eyes and visual system. These assessments provide insights into visual acuity, eye anatomy, and ocular health.
Optimal Range
For All Individuals:
Conventional Unit: 14 pts
SI Unit: Not Applicable
Normal Range
For All Individuals:
Conventional Unit: 12–14 pts
SI Unit: Not Applicable
Results That Differ From The Norm (Direct and Indirect Causes)
Abnormal results may indicate:
Achromatopsia (total color blindness)
Anomalous trichromacy (abnormal perception of colors due to a shift in sensitivity of one or more of the cone cell types)
Deuteranopia (inability to perceive green light)
Dichromacy (partial color blindness where one type of cone cell is missing or non-functional)
Monochromacy (extremely rare form of color blindness where only one type of cone cell is functional)
Protanopia (inability to perceive red light)
Tritanopia (inability to perceive blue light)
Key Reasons For Testing
Diagnosing Color Vision Deficiency: Identifies different types of color blindness, like red-green and blue-yellow deficiencies.
Occupational Needs: Evaluates color vision for jobs requiring accurate color perception, such as pilots, electricians, and designers.
Inherited Defects Screening: Detects genetic color vision problems that can affect daily activities and career choices.
Acquired Impairments: Ident...
Health Status Conditions It May Be Used To Assess
Currently, this test is not directly associated with any conditions listed on the Health Status page. However, it may be included as part of a broader set of tests linked to specific health conditions.
Some Prominent Medical Labs That May Offer This Test
Please note that this particular test has not been associated with any of the listed prominent medical labs. We recommend enquiring with your private physician or nearest hospital to determine where this specific test can be performed.
References
Important Note
Any medical procedure yielding results outside the norm may be directly or indirectly linked to the conditions outlined on this page. Various factors, including genetics, medication and supplement usage, recent illnesses, pregnancy, pre-test eating, smoking, and stress, can impact the test's outcome. Additionally, factors like false positives, false negatives, inaccurate analyses, and others can influence results.
Reference ranges, which help healthcare professionals interpret medical tests, may vary depending on age, gender, and other factors. They may also differ between laboratories due to variations in instruments and methods used. Optimal ranges are designed for preventive purposes, aiming to identify trends and potential risks early, while normal ranges reflect conventional laboratory values indicating no current disease or pathology. Your healthcare practitioner may have specific reasons for testing that deviate from the usual or may interpret results differently based on individual circumstances. Proper interpretation typically involves considering clinical findings and other diagnostic tests. Hence, it is crucial to provide your healthcare professionals with a comprehensive medical history, consult with them for result interpretation, and follow their guidance for potential re-testing or additional diagnostics.
Disclaimer
This content is provided solely for informative and educational purposes. It is not intended as a substitute for medical advice or treatment from a personal physician. Regarding the interpretation of their medical test results and/or specific health questions, it is recommended that all readers and viewers consult their physicians or other qualified health professionals. The publisher is not responsible for any adverse health effects that may result from reading or following the information in this educational content. Before beginning any nutrition, supplement, or lifestyle program, all viewers, especially those taking prescription or over-the-counter medications, should consult their physician or health care practitioner.
Please note that while prominent lab names are included in this content, we cannot guarantee that these labs offer all the tests mentioned. For confirmation, individuals should contact the labs directly or consult their medical practitioners. The information provided reflects general knowledge at the time of publication and may not include recent updates or emerging research. Readers should verify details with qualified professionals to ensure the most up-to-date and accurate guidance.
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