Protocol - Color Vision

Lighting: the Neitz Test. must be given in a well-lit area, and the light must not come from an incandescent source (regular light bulb). The test works properly under light coming from a strong fluorescent source or a combination of natural light (sunlight) and fluorescent light.

As shown in Figure 1, the Neitz Test presents a grid including one demonstration item and eight test items, which consist of a gray-scale and color pattern. The Neitz Test detects the two main classes of color blindness, red-green and blue-yellow. The Neitz Test detects both subtypes of red-green color vision (deutan and protan), and it can give an indication of the severity of red-green color blindness.

Each of the nine gray-scale and color patterns has a geometric shape embedded in it. The test panel contains a vanishing-type, desaturated geometric shape against a neutral background. A set of darker dots on each plate suggests an alternate shape that serves as a distractor.

Below each pattern are five response options: a circle, a triangle, a square, a diamond, and nothing. The examinee simply marks the option that represents what he or she sees in the grey dot pattern. Alternatively, small children are instructed to trace the shape they see in each panel with a pencil or crayon. The manual provides scripted instructions for an investigator to use in administering the protocol. The demonstration item is visible to even severely color-blind individuals and is designed to make the instructions clear. Anyone who makes one error or more on a test should be re-tested with different version of the form. The scoring key is used to obtain the test results and to identify the possible type and severity of the participants color vision deficiency.

Multiple versions of the test are available to facilitate group administration.

Figure 1. Example of Neitz Test

Sample Test Sheet for the Neitz Test of Color Vision copyright © 2001 by Western Psychological Services. Reprinted by RTI International for the sole purpose of illustration, by permission of WPS, 12031 Wilshire Boulevard, Los Angeles, California, 90025, U.S.A., www.wpspublish.com. Not to be reprinted in whole or in part for any additional purpose. All rights reserved.