Table 3.

The Comparison of Age and Spherical Equivalent Change Within the Same Grade and Across Grade

	Age Change (y)	P	SE Change (D)	P
From block 1 to block 3 in the same grade
Grade 1	0.66 ± 0.01	<0.001	−0.02 ± 0.06	0.802
Grade 2	0.65 ± 0.01	<0.001	−0.02 ± 0.09	0.825
Grade 3	0.66 ± 0.01	<0.001	−0.04 ± 0.12	0.706
From block 3 to block 1 of higher grade
Grade 1 to grade 2	0.35 ± 0.01	<0.001	−0.36 ± 0.08	<0.001
Grade 2 to grade 3	0.33 ± 0.01	<0.001	−0.50 ± 0.10	<0.001
Grade 3 to grade 4	0.46 ± 0.01	<0.001	−0.82 ± 0.14	<0.001

Block 1: born May to August 2003; Block 2: born January to April 2003; and Block 3: born September to December 2002.