# Table 3 The means of the predicted axial length vs. the true axial length

Groups SER (D) K-mean (D) Age (years)
0 to − 3.00 −3.00 to − 6.00 < − 6.00 < 42.00 42.00 to 44.00 > 44.00 6–10 11–14 15–18
M F M F M F
No. of cases (%) 518 (51.2) 413 (40.9) 80 (7.9) 177 (17.5) 515 (50.9) 319 (31.6) 219 (21.7) 241 (23.8) 206 (20.4) 221 (21.8) 66 (6.5) 58 (5.8)
Predicted AL (mm) 24.46 25.25 26.47 25.78 25.01 24.38 24.57 24.56 25.12 25.12 25.69 25.74
True AL (mm) 24.46 25.27 26.44 25.82 25.01 24.37 24.56 24.59 25.12 25.16 25.71 25.64
Error (mm) 0 −0.02 0.03 − 0.04 0 0.01 0.01 −0.03 0 −0.04 − 0.02 0.10
95% CI for error (mm) [−0.03, 0.03] [−0.02, 0.06] [− 0.07, 0.14] [− 0.10, 0.03] [−0.03, 0.03] [− 0.03, 0.04] [− 0.04, 0.05] [−0.07, 0.02] [− 0.05, 0.06] [− 0.08, 0.01] [−0.11, 0.07] [− 0.01, 0.22]
95% CI for AL (mm) [23.72, 25.18] [24.81, 26.73] [24.50, 30.14] [23.16, 26.47] [24.19, 25.82] [23.54, 25.41] [23.60, 25.92] [22.82, 25.20] [23.85, 26.59] [23.10, 25.48] [22.83, 27.52] [25.39, 31.34]
P value 0.457 0.234 0.420 0.372 0.933 0.371 0.774 0.991 0.951 0.328 0.962 0.256
1. SER = spherical equivalent refraction error; K-mean = mean K reading; AL = axial length; D = diopters; CI = confidence interval; M = male; F = female
2. Based on spherical equivalent refraction error (SER), mean K reading (K-mean), age and sex distribution of all samples