Purpose—To determine the frequency and type of color vision defects in a large group of
randomly selected older people using two versions of the D-15, and to examine the agreement
between the two tests.
Methods—The Adams desaturated D-15 test was administered under illuminant C (MacBeth
lamp, ~100 lux) to a group of 865 individuals aged 58 to 102 years of age (mean 75.2 Å} 9.1). No
exclusion criteria, other than reported presence of a congenital color defect, were applied. Testing
was binocular with habitual near correction. If any error was made on this test, the Farnsworth
D-15 was administered under identical conditions. On both tests, a color confusion score of ≥30
was considered failing and for those failing the test, color defect type (blue-yellow, red-green, or
non-selective) was determined using the method of Vingrys and King-Smith (1988).
Results—The majority (60.8%) of the people tested passed both tests. For the sample as a whole,
the failure rates of the Adams desaturated D-15 and the Farnsworth D-15 were 36.2% and 20.76%
respectively. As expected, for both tests, failure rate increased markedly with age. Among those
who failed both tests, 17.5% of the population, the proportion of specific agreement for red- green
and blue-yellow defects was high, 88%. The vast majority of those failing either or both tests had
blue-yellow defects, in agreement with prior studies.
Conclusions—Blue-yellow defects were quite common among the aged, becoming increasingly
prevalent with increasing age. More people failed the Adams’ desaturated D-15 than the
Farnsworth D-15, but among those that failed, the proportion of blue-yellow defects was similar
for the two tests, approximately 75%. The agreement between the two tests in identifying acquired
red-green and blue-yellow errors was high.