Patients with severe loss of visual acuity (as a result of genetic abnormalities) tend to also have significant loss of colour vision, but cannot carry out conventional tests based on pseudoisochomatic test plates and also have some difficulty with the relatively small stimulus employed in the CAD test. ACAD is similar to CAD in that it measures red/green and yellow/blue chromatic sensitivity, but the test stimuli are larger, spatially separated and no longer buried in a background of dynamic luminance contrast noise. The test is ideal for use in low vision patents and also in young children.
