Fig 1.
The chromaticity points of Landolt rings of 15 different colors used as target stimuli in this study.
A: The chromaticity points of 15 colors of the New Color Test at chroma 6 and the white point D65 on the Commission Internationale de l’Eclairage (CIE) 1931 chromaticity diagram, with the three confusion lines: deuteranopic (D), protanopic (P), and tritanopic (T) lines. B: Landolt rings of 15 different colors (according to the New Color Test, at chroma 6). Both the Landolt rings and background have a luminance of 30 cd/m2.
Fig 2.
Relationship between best-corrected visual acuity (BCVA) and age for all 162 participants.
BCVA was not correlated with age (Spearman’s correlation coefficient, r [95% confidence interval] = 0.0573 [-0.1204 to 0.2140], p = 0.4692).
Table 1.
Participants’ demographic information in each age group.
Fig 3.
Four representative scatterplots of color visual acuity (CVA), those of red (R), yellow-red (YR), green-yellow (GY), and blue-purple (BP), versus age, for all 162 participants.
The R- and YR-CVA values were negatively correlated with age (Spearman’s correlation coefficient, r = 0.2763, p = 0.0004 and r = 0.2619, p = 0.0008, respectively), whereas GY- and BP-CVA were not correlated with age (r = 0.0102, p = 0.8973 and r = 0.0077, p = 0.9224, respectively).
Table 2.
Results of correlation analysis between each color visual acuity and age.
Fig 4.
Comparison of the color visual acuity (CVA) values between the 15 colors.
The p-values of Dunn’s post-hoc test for comparison between CVA values for the 15 colors in all participants are summarized (ns: no significant difference, *p<0.05, **p<0.01, ***p<0.001, ****p<0.0001). The cells are shown in warmer colors (red shades) when the colors arranged vertically have significantly higher CVA values than the colors arranged horizontally, and the cells are shown in cooler colors (blue shades) when those values are significantly lower. R: red, YR: yellow-red, RY: red-yellow, Y: yellow, GY: green-yellow, YG: yellow-green, G: green, BG: blue-green, GB: green-blue, B: blue, PB: purple-blue, BP: blue-purple, P: purple, RP: red-purple, PR: purple-red.
Table 3.
Results of the 15 color visual acuities in each age group.
Fig 5.
Comparison of the variances of the color visual acuity (CVA) values between the 15 colors in all participants.
The p-values of the F-test for comparison between variances in CVA values for the 15 colors in all participants are summarized (ns: no significant difference, *p<0.05, **p<0.01, ***p<0.001, ****p<0.0001). The cells are shown in warmer colors (red shades) when the colors arranged vertically have significantly smaller variances in CVA values than those of the colors arranged horizontally, and the cells are shown in cooler colors (blue shades) when those variances are significantly larger. R: red, YR: yellow-red, RY: red-yellow, Y: yellow, GY: green-yellow, YG: yellow-green, G: green, BG: blue-green, GB: green-blue, B: blue, PB: purple-blue, BP: blue-purple, P: purple, RP: red-purple, PR: purple-red.