Table 1: Axial length, IA, and DIA in school children in Jing’an District 2nd Primary School 2016.

Axial length (mm)Sphere (−D)TA (−D)CA (−D)IA (−D)DIA (−D)
Age (yrs)MaleFemaleMaleFemaleMaleFemaleMaleFemaleMaleFemaleMaleFemale

722.93 ± 0.5622.56 ± 0.580.16 ± 0.360.29 ± 1.130.91 ± 0.930.6 ± 0.440.92 ± 0.890.6 ± 0.520.60 ± 0.370.61 ± 0.360.34 ± 0.240.31 ± 0.30
823.15 ± 0.7222.60 ± 0.780.31 ± 0.770.41 ± 0.970.89 ± 0.750.85 ± 0.560.84 ± 0.700.85 ± 0.620.63 ± 0.570.64 ± 0.370.43 ± 0.620.35 ± 0.30
923.41 ± 0.8422.94 ± 0.930.37 ± 0.650.64 ± 1.290.79 ± 0.620.84 ± 0.750.83 ± 0.670.84 ± 0.740.58 ± 0.370.72 ± 0.420.36 ± 0.260.35 ± 0.34
1023.37 ± 0.7723.08 ± 0.930.51 ± 0.970.78 ± 1.300.85 ± 0.630.76 ± 0.580.88 ± 0.650.75 ± 0.600.63 ± 0.450.61 ± 0.430.41 ± 0.400.31 ± 0.39
1123.71 ± 1.0223.26 ± 1.190.97 ± 1.311.11 ± 1.400.89 ± 0.721.04 ± 0.850.88 ± 0.741.02 ± 0.830.57 ± 0.420.69 ± 0.480.31 ± 0.360.32 ± 0.39
1224.16 ± 1.0623.78 ± 1.061.22 ± 1.371.67 ± 1.651.05 ± 0.790.90 ± 0.491.10 ± 0.840.84 ± 0.510.68 ± 0.490.71 ± 0.350.40 ± 0.400.32 ± 0.34
Average23.45 ± 0.9223.01 ± 0.990.58 ± 1.040.76 ± 1.340.89 ± 0.730.83 ± 0.640.90 ± 0.740.82 ± 0.660.61 ± 0.460.66 ± 0.410.38 ± 0.420.33 ± 0.33

TA: total astigmatism; CA: corneal astigmatism; IA: internal astigmatism; DIA: difference of internal astigmatism between both eyes. The axial length of boys was longer significantly than that of girls (, ). A linear relationship between axial length and age was found in both genders (, in male; , in female). And there was no significant difference in IA and DIA between genders (, for IA; , ). IA and DIA did not grow significantly with age in both genders (, in male, and , in female, resp.).