Table 5 Comparison of reading parameters between digital and printed optotype in the proposed method and in the study of Calabrèse et al. [16]

0.23 ± 0.19 [0.18, 0.27]

0.24 ± 0.17 [0.20, 0.28]

−0.13 ± 0.10 [−0.15, −0.12]

−0.14 ± 0.20 [−0.17, −0.11]

0.98 ± 0.18 [0.91, 1.05]

0.97 ± 0.18 [0.90, 1.03]

0.77 ± 0.40 [0.65, 0.89]

0.74 ± 0.47 [0.60, 0.88]

196.36 ± 36.09 [187.75, 204.96]

183.56 ± 38.71 [174.33, 192.79]

182 ± 39.3 [174, 186]

166 ± 39.32 [158, 170]

83.88 ± 34.47 [71.01, 96.75]

81.89 ± 38.87 [67.38, 96.4]

85 ± 48.5 [71, 100]

83 ± 60.2 [68, 104]

0.40 ± 0.21 [0.35, 0.45]

0.385 ± 0.20 [0.34, 0.43]

0.09 ± 0.07 [0.09, 0.11]

0.06 ± 0.33 [0.01, 0.11]

1.09 ± 0.19 [1.02, 1.16]

1.055 ± 0.18 [0.99, 1.12]

1.02 ± 0.75 [0.9, 1.13]

1.00 ± 0.98 [0.85, 1.15]

0.94 ± 0.20 [0.89, 0.99]

0.885 ± 0.20 [0.84, 0.93]

0.92 ± 0.16 [0.89, 0.94]

0.83 ± 0.26 [0.79, 0.87]

0.295 ± 0.14 [0.17, 0.42]

0.31 ± 0.15 [0.18, 0.43]

0.36 ± 0.22 [0.29, 0.42]

0.37 ± 0.28 [0.28, 0.45]