The City University Colour Vision Test (Ishihara-style) 3rd Edition is a widely used tool for assessing colour vision deficiency. This guide will comprehensively cover the recording sheet, its purpose, and how to interpret the results. Understanding how to correctly use and interpret the recording sheet is crucial for accurate diagnosis and management of colour vision deficiencies.
What is the City University Colour Vision Test 3rd Edition?
The City University Colour Vision Test, 3rd Edition, is a pseudoisochromatic plate test, similar to the well-known Ishihara test. It consists of a series of plates, each containing a pattern of colored dots. Individuals with normal colour vision will see a specific number or pattern within the dots, while those with colour vision deficiencies may see a different number or no number at all. This test is designed to identify various types of colour vision deficiencies, including red-green and blue-yellow deficiencies. The 3rd edition often incorporates improvements in plate design and testing methodology compared to earlier versions.
Understanding the Recording Sheet
The recording sheet for the City University Colour Vision Test 3rd Edition provides a structured format for documenting the responses of the individual being tested. Typically, it lists the plate number and a space for recording the response. There is usually also a space for demographic information such as the patient's name, age, and date of the test. Some recording sheets may include additional sections for noting any observations made during the test or any other relevant information. The precise format of the recording sheet may vary slightly depending on the supplier.
How to Use the Recording Sheet
The process is straightforward:
- Administer the Test: Present each plate to the individual being tested in the correct order, ensuring consistent lighting conditions.
- Record the Response: For each plate, meticulously record the individual's response in the designated space on the recording sheet. This should be the number or pattern they see, or a notation like "none seen" or a description if they perceive something other than the expected response.
- Note Any Observations: Make a note of any unusual behaviour or comments from the individual being tested. This could include prolonged response times, hesitancy, or any verbal cues. This contextual information can be crucial in interpreting results.
- Review and Interpretation: Once the test is completed, carefully review the responses and compare them to the key.
What Do the Results Mean?
The interpretation of results hinges on comparing the responses recorded on the sheet with the provided key. A consistent failure to identify the correct numbers or patterns on specific plates indicates a colour vision deficiency. The specific plates missed will provide clues to the type and severity of the deficiency. It’s important to remember that the recording sheet itself doesn't diagnose; it provides the raw data for interpretation by a qualified professional (e.g., an ophthalmologist or optometrist).
What if the person being tested cannot see any numbers?
If the individual consistently reports not seeing numbers or patterns on several plates, this strongly suggests a colour vision deficiency. The pattern of incorrect responses provides important information regarding the specific type and severity of the deficiency. A comprehensive evaluation by an eye care professional is then essential.
How accurate is the City University Colour Vision Test 3rd Edition?
The accuracy of the City University Colour Vision Test 3rd Edition, like other pseudoisochromatic plate tests, is generally high for detecting common types of colour vision deficiency. However, it’s important to consider that no test is perfectly accurate. False positives or negatives can occur, depending on factors like lighting conditions, the individual's attention, and the presence of other eye conditions.
Are there other color vision tests available?
Yes, several other tests are available, including the Ishihara test, the Farnsworth-Munsell 100-hue test, and the Lanthony D-15 test. Each test has its own strengths and limitations, and the choice of test depends on various factors such as the purpose of testing and the suspected type of color vision deficiency.
This guide provides a solid overview of the City University Colour Vision Test 3rd Edition recording sheet and its use. Remember, accurate interpretation requires professional expertise. Always consult a qualified eye care professional for a proper diagnosis and management of any colour vision deficiency.
