Relationship between Myopia Progression and School Entrance Age: A 2.5-Year Longitudinal Study

Table 3

2.5-year progression of myopia and changes in ocular biological structure parameters between different grades in the 7- and 8-year-old schoolchildren.

	Grade 1	Grade 2	Grade 3	t	value
Change SE, D
7 years old	−0.45 ± 0.99	−0.56 ± 1.22	N/A	1.038	0.3
8 years old	N/A	−0.54 ± 1.01	−0.75 ± 1.26	2.124	0.034
Change AL, mm
7 years old	0.59 ± 0.34	0.62 ± 0.34	N/A	−1.822	0.069
8 years old	N/A	0.57 ± 0.37	0.61 ± 0.35	−1.108	0.268
Change AL/Change CR
7 years old	0.07 ± 0.04	0.07 ± 0.05	N/A	−0.864	0.388
8 years old	N/A	0.07 ± 0.04	0.08 ± 0.06	−1.514	0.131
Change SE/Change AL(D/mm)
7 years old	−0.38 ± 1.5	−0.33 ± 2.65	N/A	−0.253	0.8
8 years old	N/A	−0.25 ± 1.65	−0.78 ± 1.78	3.446	0.001

Comparisons of change of refraction and refractive components among different grades’ students using the t-test.